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High-intensity interval training (HIIT) prescriptions manipulate intensity, duration, and recovery variables in multiple combinations. Researchers often compare different HIIT variable combinations and treat HIIT prescription as a "maximization problem", seeking to identify the prescription(s) that induce the largest acute VO2/HR/RPE response. However, studies connecting the magnitude of specific acute HIIT response variables like work time >90% of VO2max and resulting cellular signalling and/or translation to protein upregulation and performance enhancement are lacking. This is also not how successful endurance athletes train. First, HIIT training cannot be seen in isolation. Successful endurance athletes perform most of their training volume below the first lactate turn point (

The present investigation aimed to study the cardiovascular responses and the cerebral oxygenation (Cox) during exercise in acute hypoxia and with contemporary mental stress. Fifteen physically active, healthy males (age 29.0 ± 5.9 years) completed a cardiopulmonary test on a cycle ergometer to determine the workload at their gas exchange threshold (GET). On a separate day, participants performed two randomly assigned exercise tests pedaling for 6 min at a workload corresponding to 80% of the GET: (1) during normoxia (NORMO), and (2) during acute, normobaric hypoxia at 13.5% inspired oxygen (HYPO). During the last 3 min of the exercise, they also performed a mental task (MT). Hemodynamics were assessed with impedance cardiography, and peripheral arterial oxygen saturation and Cox were continuously measured by near-infrared spectroscopy. The main results were that both in NORMO and HYPO conditions, the MT caused a significant increase in the heart rate and ventricular filling rate. Moreover, MT significantly reduced (74.8 ± 5.5 vs. 62.0 ± 5.2 A.U.) Cox, while the reaction time (RT) increased (813.3 ± 110.2 vs. 868.2 ± 118.1 ms) during the HYPO test without affecting the correctness of the answers. We conclude that in young, healthy males, adding an MT during mild intensity exercise in both normoxia and acute moderate (normobaric) hypoxia induces a similar hemodynamic response. However, MT and exercise in HYPO cause a decrease in Cox and an impairment in RT. [ABSTRACT FROM AUTHOR]

Purpose: Individuals with constitutional thinness have been presented with a lower muscular energy metabolism at the cellular level but their effective aerobic capacities and exercise-related energy efficiency remains unexplored. The present study compares maximal and sub-maximal aerobic capacities between subjects with constitutional thinness and age-matched normal-weight ones. Methods: Anthropometric measures, body composition (Dual-X-ray absorptiometry), physical activity and sedentary time (GT3x actigraphs), and maximal aerobic capacities (cycling V ˙ O 2peak test) were assessed in 18 constitutionally thin (CT—body mass index < 17.5 kg m−2) and 17 normal-weight (NW—body mass index between 20 and 25 kg m−2) women. Energy efficiency was assessed during a submaximal cycling test and a walking exercise. Results: CT had a lower body mass and body mass index compared to NW. Absolute peak oxygen uptake and maximal aerobic power were lower in CT subjects compared to NW (ES: − 1.63 [− 2.40; − 0.86] and − 1.32 [− 2.05; − 0.58], p < 0.001). V ˙ O 2peak related to body mass was not different between groups. Gross and net efficiency (ES: − 0.78 [− 1.48; − 0.06], p = 0.03 and ES: − 0.73 [− 1.43; − 0.01], p = 0.05) were lower in CT compared to NW during the submaximal cycling exercise. The gross energy cost of walking related to body mass was lower in subjects with CT (ES: − 1.80 [− 2.60; − 0.97, p = 0.05), with no difference for the net one. Perceived exertion was similar between groups in responses to both submaximal exercises. Conclusion: Constitutionally thin women do not show impaired aerobic capacities at moderate to maximal intensities despite lower energy efficiency while cycling and walking at low-to-moderate intensities. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the agreement between the two Gas Exchange Thresholds (GETs = GET1 and GET2), identified by the conventional V-Slope method, and two Respiratory Frequency Thresholds (fRTs = fRT1 and fRT2) obtained from a novel, low-cost, and simple method of breakpoint determination. Methods: Fifty middle-aged males (age: 50–58 years; V ˙ o2peak: 37.5 ± 8.6 mL·Kg−1·min−1), either healthy or with chronic illnesses, underwent an incremental cycle exercise test to determine maximal oxygen uptake ( V ˙ o2max/ V ˙ o2peak), GETs and fRTs. Results: There were no statistical differences [P > 0.05; ES: 0.17 to 0.32, small] between absolute and relative (56–60% V ˙ o2peak) oxygen uptake ( V ˙ o2) values at GET1 with those obtained at fRT1, nor between V ˙ o2 values at GET2 with those at fRT2 (76–78% V ˙ o2peak). Heart rate (HR) at fRT1, and V ˙ o2 and HR at fRT2 showed very large correlations (r = 0.75–0.82; P < 0.001) and acceptable precision (SEE < 7–9%) in determination of their corresponding values at GET1 and GET2. The precision in the estimation of V ˙ o2 at GET1 from fRT1 was moderate (SEE = 15%), while those of power output at GET1 (SEE = 23%) and GET2 (SEE = 12%) from their corresponding fRTs values were very poor to moderate. Conclusion: HR at fRT1 and V ˙ o2 and HR at fRT2, determined using a new objective and portable approach, may potentially serve as viable predictors of their respective GETs. This method may offer a simplified, cost-effective, and field-based approach for determining exercise threshold intensities during graded exercise. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the influence of sodium bicarbonate (SB) supplementation on physical performance, neuromuscular and metabolic responses during CrossFit® exercise. Seventeen Advanced CrossFit®-trained athletes completed the randomized, double-blind, placebo-controlled crossover protocol consisting of four visits, including two familiarization sessions and two experimental trials separated by a 7-day washout period. Participants supplemented 0.3 g/kg body mass (BM) of SB or placebo 120-min prior to performing the CrossFit® benchmark Fran followed by 500 m of rowing. SB improved time to complete Fran compared to PLA (291.2 ± 71.1 vs. 303.3 ± 77.8 s, p = 0.047), but not 500 m rowing (112.1 s ± 7.9 vs. 113.2 s ± 8.9 s, p = 0.26). No substantial side-effects were reported during the trials. This study showed that SB improved CrossFit® benchmark Fran performance, but not subsequent 500-m rowing. These data suggest that SB might be an interesting supplementation strategy for CrossFit® athletes. [ABSTRACT FROM AUTHOR]

Purpose of review: Hypertension-induced cardiac hypertrophy is widely known as a major risk factor for increased cardiovascular morbidity and mortality. Although exercise is proven to exert overall beneficial effects on hypertension and hypertension-induced cardiac hypertrophy, there are some concerns among providers about potential adverse effects induced by intense exercise, especially in hypertensive athletes. We will overview the underlying mechanisms of physiological and pathological hypertrophy and delineate the beneficial effects of exercise in young people with hypertension and consequent hypertrophy. Recent findings: Multiple studies have demonstrated that exercise training, both endurance and resistance types, reduces blood pressure and ameliorates hypertrophy in hypertensives, but certain precautions are required for hypertensive athletes when allowing competitive sports: Elevated blood pressure should be controlled before allowing them to participate in high-intensity exercise. Non-vigorous and recreational exercise are always recommended to promote cardiovascular health. Summary: Exercise-induced cardiac adaptation is a benign and favorable response that reverses or attenuates pathological cardiovascular remodeling induced by persistent hypertension. Exercise is the most effective nonpharmacological treatment for hypertensive individuals. Distinction between recreational-level exercise and competitive sports should be recognized by medical providers when allowing sports participation for adolescents and young adults. [ABSTRACT FROM AUTHOR]

(1) Background: Heart failure with preserved ejection fraction (HFpEF) is a clinical challenge, with limited success from current therapeutic strategies. This study aimed to assess the impact of combined exercise (CE) and high-intensity interval training (HIIT) on key biomechanical parameters during the 6-minute walk test (6MWT) in HFpEF patients. (2) Methods: A randomized controlled trial was conducted in 76 sedentary HFpEF patients, divided into three groups as follows: the CE, HIIT, and control groups. CE involves aerobic and strength training, whereas HIIT includes high-intensity intervals. Cadence (steps per minute), distance, maximum heart rate (HRmax), and exercise intensity were measured pre- and postintervention. (3) Results: The results revealed significant improvements in cadence in the CE group compared with the control group (p = 0.009) for intention-to-treat analysis, and in the control and HIIT groups (p = 0.002) for per-protocol analysis. CE also significantly improved HRmax and exercise intensity, suggesting an enhanced cardiovascular response. In contrast, HIIT did not significantly affect these parameters. The correlation between cadence and distance covered during the 6MWT was strong in the overall group (r = 0.762, p < 0.001). (4) Conclusions: These findings suggest that CE is an effective intervention to improve gait efficiency, cardiovascular response, and functional capacity in HFpEF patients, whereas HIIT may require further investigation in this population. [ABSTRACT FROM AUTHOR]

Introduction. Physical activity is vital for preventing and managing lifestyle-related diseases, which pose significant health and socio-economic challenges. This study aimed to evaluate the effects of a six-month supervised physical activity program on health risk factors and body composition in middle-aged individuals with overweight or obesity. Methods. The study involved 166 men and women aged 30 to 65 years, with a body mass index (BMI) ranging from 26 to 35 and moderate to severe health risks. Participants of the study were engaged in a six-month physical activity training program designed in accordance with World Health Organization guidelines. Comprehensive assessments were performed at baseline and after the intervention, including measurements of various anthropometric and body composition parameters, as well as evaluations of functional performance. Fitness tests were also conducted to assess participants' physical capacity and to monitor improvements throughout the training period. Results. Baseline measures of body mass composition and age demonstrated a strong positive correlation with visceral fat rating (VFR) in both men (r = 0.364, p < 0.001) and women (r = 0.420, p = 0.002). Following the six-month training program, participants exhibited an average improvement of 30% (p < 0.001) in their Cooper endurance test results. The physical activity intervention positively impacted body mass index (BMI) and various body composition metrics, including fat mass, VFR, and muscle mass, across all participants and most subgroups (gender, BMI, and age). In males, training at higher maximum heart rate (HRmax) zones significantly contributed to a reduction in the percentage of fat mass (80–89% HRmax) and an increase in the percentage of muscle mass (70–79% and 80–89% HRmax). Conclusions. The study indicates that a six-month supervised physical activity program significantly improves health risk factors and body composition (visceral fat reduction and improvement in percent of fat and muscle mass) among middle-aged individuals with overweight or obesity. Therefore, we advocate for the integration of structured physical activity interventions into healthcare practices to effectively enhance health outcomes in this population. [ABSTRACT FROM AUTHOR]

Osteoporosis results in low-trauma fractures affecting millions globally, in particular elderly populations. Despite the inclusion of physical activity in fracture prevention strategies, the optimal bone-strengthening exercises remain uncertain, highlighting the need for a deeper understanding of lower limb joint loading dynamics across various exercise types and levels. This study examines lower limb joint loading during high-impact exercises across different intensities. A total of 40 healthy, active participants were recruited (mean ± SD: age of 40.3 ± 13.1 yr; height 1.71 ± 0.08 m; and mass 68.44 ± 11.67 kg). Motion capture data and ground reaction forces of 6 different exercises: a self-selected level of walking, running, countermovement jump, squat jump, unilateral hopping, and bilateral hopping were collected for each participant. Joint reaction forces were estimated using lower body musculoskeletal models developed in OpenSim. Running and hopping increased joint forces compared to walking, notably at the hip (83% and 21%), knee (134% and 94%), and ankle (94% and 77%), while jump exercises reduced hip and ankle loading compared to walking (36% and 19%). Joint loading varied with exercise type and intensity, with running faster increasing forces on all joints, particularly at the hip. Sprinting increased forces at the hip but lowered knee and ankle forces. Higher jumps intensified forces on all joints, while faster hopping reduced forces. The wide variation of lower limb joint loading observed across the exercises tested in this study underscores the importance of implementing diverse exercise routines to optimize overall bone health and strengthen the musculoskeletal structure. Practitioners must therefore ensure that exercise programs include movements that are specifically suitable for their intended purpose. Lay Summary: Osteoporosis is a global health concern, particularly among the elderly, leading to increased risk of fractures. Although physical activity is recommended to prevent fractures, the most effective bone-strengthening exercises remain unclear. This study aimed to quantify how different high-impact exercises affect lower limb joint loading dynamics. Forty healthy, active participants with an average age of 40 yr performed 6 exercises: walking, running, jumping, and hopping, at various intensities. Motion capture technology and computational modeling were used to analyze joint forces at the hip, knee, and ankle. Results showed that running and hopping increased joint forces compared to walking, particularly at the hip and knee. Conversely, jumping exercises reduced hip and ankle loading. Joint loading varied across exercise types and intensities; for example, running faster increased forces primarily on the hip, while jumping higher increased forces on all joints. Conversely, faster hopping reduced forces. These findings highlight the importance of incorporating diverse exercises into bone-strengthening routines to optimize overall bone health and musculoskeletal strength. Healthcare practitioners should tailor exercise programs to individual needs, ensuring they include appropriate movements for desired outcomes. Graphical Abstract [ABSTRACT FROM AUTHOR]

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Context Ghrelin circulates in acylated (AG) and deacylated (DAG) forms, which are known to affect appetite. Although acute exercise has been shown to modulate ghrelin levels, data on the impact of exercise intensity on AG and DAG levels and their effects on appetite are sparse and primarily limited to males. Objective To investigate the effect of exercise intensity and sex on ghrelin levels and appetite in untrained humans. Methods Eight males (age: 43.1 ± 10.9 years; body mass index [BMI]: 22.2 ± 1.7 kg/m2; peak oxygen consumption [VO2peak]: 36.3 ± 6.4 mL/kg/min) and 6 females (age: 32.2 ± 11.1 years; BMI: 22.7 ± 1.0 kg/m2; VO2peak: 29.2 ± 4.0 mL/kg/min) completed a maximal graded cycle ergometer lactate threshold (LT)/VO2peak test. These data were used to determine the exercise intensity on 3 subsequent randomized control or calorically matched cycle exercise bouts: (1) CON, no exercise; (2) MOD, the power output at LT; (3) HIGH, the power output associated with 75% of the difference between LT and VO2peak. Perception of appetite was analyzed using visual analog scales. Results Females had higher levels of total ghrelin (TG) (P =.03) and DAG (P =.01) at baseline than males. Both groups exhibited reduced DAG levels in HIGH compared with MOD and CON (P <.0001-.004); however, only females had significantly reduced AG in HIGH (P <.0001). Hunger scores were higher in MOD than in CON (P <.01). Conclusion High-intensity may be superior to moderate-intensity exercise for reducing ghrelin levels and modifying hunger, and sex may impact this response. [ABSTRACT FROM AUTHOR]

This study aimed to compare acute physiological responses during the W prime (W´) balance training model (W´BAL-INT) with performance in the critical power test (CPTest). Additionally, the study sought to determine the extent of neuromuscular and metabolic fatigue associated with severe and extreme intensity domains. Fourteen road master cyclists (13 male, 1 female) completed graded incremental exercise tests to determine their maximum oxygen uptake and 12-, 7- and 3-min maximal efforts to assess CP and W´ (CPTest). Additionally, they participated in a reconstitutive intermittent training session following the W´BAL-INT model. Physiological responses including oxygen uptake (V̇O2), the heart rate (HR), blood lactate (BLa¯) concentration, and perceptual responses (RPE), were measured and compared to CPTest performance data. The W´BAL-INT induced steady-state physiological responses in V̇O2mean (F = 0.76, p = 0.655) and absolute HR, relative HR and HRCP (F = 0.70, p = 0.704; F = 1.11, p = 0.359; F = 1.70, p = 0.095, respectively) comparable to CPTest. During the 3-min work intervals in the training session, V̇O2 was stable and similar to V̇O2peak (54.2 ± 6.7 to 59.3 ± 4.9 ml·kg-1·min-1) in the CPTest. Furthermore, 4-min rest intervals facilitated recovery up to moderate fatigue levels (80-100% of W´ balance). HR responses were sensitive to interval intensity and accumulated time. Meanwhile, BLa¯ responses and the RPE increased fatigue development during W´BAL-INT. The W´BAL-INT training model generates consistent physiological responses in mean oxygen kinetics, the percentage of CP and the HR, similar to those observed during the CPTest. However, different physiological responses were observed in peak oxygen kinetics and W´ energy balance. [ABSTRACT FROM AUTHOR]

Background/objective: To examine the cognitive benefits of 6  months of prescribed intermittent exercise (10-min bouts totaling 150 weekly minutes) in community-dwelling older adults, comparing effects of low-intensity movement (LIM) and moderate-intensity aerobic exercise (aerobic exercise; AE) training; and exploring biological mechanisms of exercise-related cognitive improvement. Method: Twenty-five adults (>60  years old) participated in a 6-month controlled trial and were randomized into LIM or AE intermittent training. Cognition was assessed using a neuropsychological test battery including the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), California Verbal Learning Test, 2nd Edition (CVLT-II), and Delis-Kaplan Executive Function System (D-KEFS). Neuroimaging measures were collected using a 7  T human MRI scanner. Serologic neurotrophic and inflammatory factors were analyzed using Luminex multiplex assays [brain derived neurotrophic factor (BDNF); vascular endothelial growth factor (VEGF)]; interleukin-6 (IL-6), C-reactive protein (CRP), plasminogen activator inhibitor (PAI-1). Results: LIM and AE intermittent training had dissociable effects on cognition, with LIM resulting in improved learning and memory and AE resulting in improved executive functioning. Intervention groups differed on change in cognitive performance on CVLT-II learning and D-KEFS trail making test. Increase in right dorsolateral prefrontal cortex (DLPFC) surface area was linked to executive improvement (i.e., phonemic fluency) regardless of intervention group. A decline in circulating PAI-1 was linked to learning and memory improvement in response to LIM over 6 months. Conclusion: Moderate-intensity AE and LIM intermittent training likely have distinct cognitive benefits, though low-intensity activity is often included as a control group in exercise trials in aging. [ABSTRACT FROM AUTHOR]

Background: Gestational Diabetes Mellitus (GDM) affects 14.0% of pregnancies globally, with a 35% post-pregnancy relapse and a 60% risk of Type 2 Diabetes (T2D) within 5-10 years. Challenges in long-term management, especially postpartum, include adherence and follow-up difficulties. Methods: This study, based on a systematic review and meta-analysis, examined the practical effects of exercise therapy in the prevention, treatment, and prevention of progression from Gestational Diabetes Mellitus (GDM) to Type 2 Diabetes (T2D). Relevant research and clinical practices were retrieved from six major databases (PubMed, Scopus, Web of Science, Cochrane Library, MEDLINE, Science Direct). After analyzing the intervention effects of exercise therapy at different stages, factors favorably influencing the effectiveness of exercise intervention were identified during the more effective stages. Finally, a longterm and efficient exercise implementation plan for the comprehensive management of GDM was proposed. Results: In GDM prevention, exercise reduced the post-intervention risk by 37% compared to the control group (Relative Risk (RR)=0.63; 95% Confidence Interval (CI): 0.54 to 0.72; p=0.01). Studies on GDM treatment showed improved glucose control in the exercise group post-intervention (Mean Difference (MD)=-0.10; 95% CI: -0.16 to -0.04; p=0.04/MD=-0.27; 95% CI: -0.36 to -0.19; p<0.0001). However, exercise therapy didn't significantly affect the incidence of T2D post-GDM (RR=0.88; 95% CI: 0.69 to 1.11; p=0.39) due to challenges in quantified exercise prescriptions and the complexity of postpartum programs. Conclusion: To enhance exercise therapy effectiveness in GDM management, the study recommends adopting an integrated model emphasizing personalized pregnancy plans, postpartum strategies, and long-term support. Leveraging frequent healthcare contact during pregnancy can establish and sustain exercise habits, fostering a lifelong pattern. While the study acknowledges limitations, this approach holds potential for improving glycemic metabolism and developing healthy exercise habits in subsequent generations. Future research should include longer follow-ups to validate the practical efficacy of this approach in preventing T2D after GDM. [ABSTRACT FROM AUTHOR]

This study compared the effect of high and low levels of virtual reality (VR) immersion during moderate and high intensity cycling-exercise in younger (18–35 years), middle-aged (36–50 years), and older (51–69 years) adults. Thirty participants (5 female and 5 males per age group) completed moderate (steady state: 15 minutes at 60–75% maximum heart rate (MHR)) and high (sprint: 10 x 30 second sprints at 75–85% MHR) intensity cycling in four conditions: VR using a head-mounted display (High HMD), room-projector (Low Room), screen-projector (Low Screen) and No VR. Exercise performance measures (cadence, distance, power output) were recorded. Following each VR condition, exercise enjoyment (PACES) and exercise engagement (Flow State Scale) were measured. Results showed that exercise intensity had a significant effect of age on; heart rate (steady state and sprint), cadence (sprint) and distance (sprint) (p's <0.05). A significant effect of condition was observed during the sprint exercise for heart rate (p < 0.05). No other significant condition effects were observed for exercise performance. Significant effects of condition were identified for exercise engagement relating to sense of control (p < 0.01) and loss of self-consciousness (p < 0.05) with the highest values occurring in the Low Screen condition for all age groups, while transformation of time was significantly different (p < 0.05) for the middle-aged adults (highest during High VR and Low Screen). These results indicate that irrespective of age, participants found themselves in control and immersed more during the Low Screen VR condition than the other VR and No VR conditions. The findings indicate that VR immersion impacts exercise performance and exercise engagement in different age-groups and therefore should be considered when using VR to promote exercise behaviour. [ABSTRACT FROM AUTHOR]

Background: To explore the effects of different dose of aerobic exercise on motor function, balance, mobility, and quality of life in Parkinson's disease patients, aiming to provide insights into determining the optimal aerobic exercise dose for treating PD. Methods: Searching was conducted in four databases: PubMed, Embase, Web of Science, and Cochrane. The dose of aerobic exercise intervention was evaluated based on the recommendations of the American College of Sports Medicine regarding the development and maintenance of cardiorespiratory health, muscle strength, and functional mobility in patients with PD. The exercise intervention dose of the included studies were first classified into high ACSM compliance and low ACSM compliance based on meeting 4/6 of the ACSM recommendations. The reliability of the results was then validated using the criterion of meeting 5/6 of the ACSM recommendations. Comparisons of the effects of aerobic exercise dose on Motor function, Balance, Mobility, and QOL in PD patients using standardized mean difference with 95% confidence intervals. Results: When using the 4/6 ACSM compliance criterion, 17 studies were categorized as high ACSM compliance and 12 as low ACSM compliance. The SMD ratios for high versus low ACSM compliance were: UPDRS-III (-0.79: -0.18), BBS (0.60: 0.05), TUG (-0.60: -0.60), and QOL (-1.05: -0.15). When using the 5/6 ACSM compliance criterion, 11 studies were categorized as high ACSM compliance and 19 as low ACSM compliance. The SMD ratios for high versus low ACSM compliance were: UPDRS-III (-0.95: -0.38), BBS (0.48: 0.37), TUG (-0.71: -0.55), and QOL (-0.7: 0.04). Conclusion: This study provides preliminary support for the potential of aerobic exercise to improve certain clinical symptoms in patients with PD. Furthermore, the results indicate that compliance to higher doses of aerobic exercise, as per ACSM standards, may contribute to improvements in motor function, balance, mobility, and quality of life for patients with PD. However, due to the heterogeneity in the studies and the influence of factors that have not yet been fully explored, these conclusions should be interpreted with caution. More highquality randomized controlled trials are needed in the future to further verify and clarify the effects of aerobic exercise. [ABSTRACT FROM AUTHOR]

Objective: This study investigates the causal relationship between moderate to vigorous physical activity and cognitive performance. Methods: Genetic loci strongly related to moderate to vigorous physical activity from genome-wide association studies were used as instrumental variables. These were combined with genetic data on cognitive performance from different Genome-Wide Association Study (GWAS) to conduct a two-sample Mendelian randomization analysis. The primary analysis used inverse variance weighting within a random effects model, supplemented by weighted median estimation, MR-Egger regression and other methods, with results expressed as Beta coefficient. Results: This study selected 19 SNPs closely related to physical activity as instrumental variables. The multiplicative random-effects Inverse-Variance Weighted (IVW) analysis revealed that moderate to vigorous physical activity was negatively associated with cognitive performance (Beta = -0.551; OR = 0.58; 95% CI: 0.46-0.72; p < 0.001). Consistent results were obtained using the fixed effects IVW model (Beta = -0.551; OR = 0.58; 95% CI: 0.52-0.63; p < 0.001), weighted median (Beta = -0.424; OR = 0.65; 95% CI: 0.55-0.78; p < 0.001), simple mode (Beta = -0.467; OR = 0.63; 95% CI: 0.44-0.90; p < 0.001), and weighted mode (Beta = -0.504; OR = 0.60; 95% CI: 0.44-0.83; p < 0.001). After adjusting for BMI, smoking, sleep duration, and alcohol intake frequency, the multivariate MR analysis also showed a significant association between genetically predicted MVPA and cognitive performance, with Beta of -0.599 and OR = 0.55 (95% CI: 0.44-0.69; p < 0.001). Conclusion: The findings of this study indicate that genetically predicted moderate to vigorous physical activity may be associated with a decline in cognitive performance. [ABSTRACT FROM AUTHOR]

Background: Obesity and type 2 diabetes (T2D) are associated with alterations in testosterone concentrations. While evidence indicates that aerobic training can influence testosterone in healthy populations or females with hyperandrogenism, its impact in individuals with obesity or T2D remains unclear. Thus, the aim of this study was to investigate whether aerobic training can influence circulating testosterone concentrations in individuals with obesity or T2D. Methods: EBSCOhost (CINAHL, MEDLINE, SPORTDiscus), PubMed and Embase were searched for articles published until August 2023. Eligible articles included individuals with obesity or T2D that underwent an aerobic exercise intervention with testosterone concentrations measured at baseline and post intervention. Two reviewers independently screened the seven articles included in this meta-analysis and conducted data extraction and risk of bias assessments. Results: A total of 103 participants (62 men / 41 women) from three randomised controlled trials and four non-randomised controlled trials were included. Effect sizes were computed with random effects models. Aerobic exercise moderately increased testosterone concentrations in men (g = 0.565, 95% CI = 0.307 to 0.822, p < 0.001), but had no significant effect in women (g = -0.523, 95% CI = -1.541, 0.496, p = 0.314). Aerobic exercise had no significant effect on sex hormone-binding globulin or markers of insulin sensitivity (p > 0.05). Conclusions: Aerobic training may be used to increase testosterone concentrations in men with obesity or T2D, but potentially has no influence in women. Given the low number of studies, further studies investigating the effect of exercise on circulating sex hormones in men and women with obesity or T2D are needed. Key Points: • Aerobic exercise training can significantly increase testosterone concentrations in men who are obese or have type 2 diabetes. • Aerobic exercise training does not appear to significantly influence testosterone concentrations in women who are obese or have type 2 diabetes. • Aerobic exercise training could be utilised to improve testosterone concentrations in men who are obese or have type 2 diabetes. [ABSTRACT FROM AUTHOR]

AbstractObjectivesMethodsResultsConclusions\nIMPLICATIONS FOR REHABILITATION1) to develop two maximum heart rate (HRmax) prediction equations for individuals after stroke; 2) to investigate its validity.The HRmax was obtained by a Cardiopulmonary Exercise Test (CPET). Participants also completed the Six-minute Walking Test (6MWT) and the Incremental Shuttle Walking Test (ISWT).60 individuals (54(12) years; 64(69) months after stroke) were included. Twenty individuals (58(10) years; 67(61) months after stroke) were included in the cross-validation group. For the first model, the following equation was generated (equation-1): HRmax= 87.655 + 0.726 (HRpeak in the 6MWT) − 0.386 (age in years), (R2=0.53; Standard Error of the Estimate (SEE)= 15.35; p < 0.0001). For the second model, the following equation was generated (equation-2): HRmax= 96.523 + 0.681 (HRpeak in the ISWT) − 0.039 (walking distance in meters in the ISWT) − 0.400 (age in years), (R2=0.53; SEE = 15.51; p < 0.0001). Significant and high magnitude agreement was found between the HRmax obtained by the CPET and the predicted HRmax by equation-1 (ICC= 0.85; 95% CI= 0.63 − 0.94) and equation-2 (ICC= 0.72; 95% CI= 0.29 − 0.89).Two HRmax prediction equations have been developed and showed adequate validity. Professionals will have the option of choosing one of the two equations to use.Two maximum heart rate prediction equations, with clinical applicability and adequate validity, were provided for individuals after strokeTo apply the equations, it is necessary to perform the Six-Minute Walking Test or the Incremental Shuttle Walking Test.Both equations are valid and suitable for use in this population for the prescription of aerobic exercise intensity in clinical practice.Two maximum heart rate prediction equations, with clinical applicability and adequate validity, were provided for individuals after strokeTo apply the equations, it is necessary to perform the Six-Minute Walking Test or the Incremental Shuttle Walking Test.Both equations are valid and suitable for use in this population for the prescription of aerobic exercise intensity in clinical practice. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the changes in pain following exercise sessions with different intensities in patients who underwent total knee arthroplasty (TKA). Methods: This is a repeated measure and single-blinded randomized controlled study. Thirty-six patients who underwent TKA (age, 64.9 ± 7.42 years) were randomly assigned to either low-intensity exercises (LIEs) group or high-intensity exercises (HIEs) group. Exercise programs lasted for five days during the hospitalization period. Pain intensity was assessed by visual analog scale (VAS) and pressure pain thresholds (PPTs) were measured over quadriceps and biceps brachii and muscles immediately before and after exercise. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) subscale (pain, stiffness, and physical function) scores were recorded at two points in baseline and discharge from the hospital. Results: The pain intensity decreased in patients in both groups after TKA. PPTs increased in both groups at all tested sites following the first, third, and fifth exercise bouts. HIE program had a greater positive effect on the pain intensity after the first exercise session than LIE program on the PPTs (p < 0.05). HIE program was more effective in order to reduce pain severity immediately after the exercise sessions in patients (d: 0.5, p < 0.05). WOMAC scores significantly improved in both groups during the discharge from the hospital (p = 0.001). Conclusion: Our results found that both LIE and HIE programs performed during hospitalization after TKA declined pain intensity. Particularly notable were the substantial improvements observed in managing post-operative pain, especially following the second exercise session. The HIE program proved more effective in improving stiffness, and enhancing physical function. [ABSTRACT FROM AUTHOR]

In giant slalom, the ability to apply a high amount of force in the radial direction is essential for performance. A race is characterized by repeated turns performed at high velocity, potentially inducing fatigue. Therefore, this study aimed to assess the effect of fatigue on performance, trajectory characteristics, and force production capacities onto the snow. Twelve skiers ran a 4-turn section with (FATIGUE) and without pre-induced fatigue (CONTROL). Knee extensor maximal voluntary contraction (MVC) was performed before the experiment and after both conditions. Section time, energy dissipation, path length, total force output, force application effectiveness, and EMG activity of the main lower-limb muscles were compared between conditions. Multiple linear regressions were used to understand whether interindividual variability in the kinematic, kinetic and EMG between conditions explains variability in performance changes with fatigue. MVC was lower after FATIGUE (−19.1 ± 6.4%, p < 0.001) but did not change after CONTROL. FATIGUE was associated with longer section times (+0.21 ± 0.11 s, p < 0.001), energy dissipation (−0.78 ± 1.05 J.s.kg.m−1, p = 0.026), path length (+1.1 ± 1.6 m, p = 0.033) and lower force application effectiveness (−0.1 ± 0.1, p = 0.017). This study experimentally demonstrates that fatigue in giant slalom results in lower force application effectiveness, inducing over-dissipation of mechanical energy and longer path length, leading to lower performance. [ABSTRACT FROM AUTHOR]

This study presents a novel method for evaluating the submaximal velocity-force (V(F)) relationship in mountain ultramarathon races using crowdsourced data from Strava.com. The dataset includes positional data from 408 participants of the 171-km UTMB® 2023 race (9,850-m D+). The race was divided into 100-m segments. The mean net propulsive force and velocity were computed for each segment to describe the submaximal V(F) relationship as a rational function of three parameters. F1: propulsive force at 1 m · s−1; V0: theoretical maximum velocity on flat terrain; C: curvature parameter (the lower C, the more linear the V(F) relationship). The V(F) profile parameters were found to be F1 = 1.80 ± 0.33 N · kg−1, V0 = 2.36 ± 0.42 m · s−1, and C = 0.66 ± 1.81, with good independence between the parameters within a group of homogeneous performance. The best athletes had the highest F1, V0, and C values. V(F) parameters were affected by fatigue during the race, with decreases of 20.9%, 32.0%, and 59.8% between the first and second parts of the race respectively. These findings suggest that the V(F) relationship is an interesting original approach for studying performance and fatigability during mountain ultra-endurance races. [ABSTRACT FROM AUTHOR]

A strict correlation among proximal tubule epithelial cell dysfunction, proteinuria, and modulation of the Renin-Angiotensin System and Kalikrein-Kinin System are crucial factors in the pathogenesis of Acute Kidney Injury (AKI). In this study, we investigated the potential protective effect of preconditioning by moderate-intensity aerobic exercise on gentamicin-induced AKI. Male Wistar rats were submitted to a moderate-intensity treadmill exercise protocol for 8 weeks, and then injected with 80 mg/kg/day s.c. gentamicin for 5 consecutive days. Four groups were generated: 1) NT+SAL (control); 2) NT+AKI (non-trained with AKI); 3) T+SAL (trained); and 4) T+AKI (trained with AKI). The NT+AKI group presented: 1) impairment in glomerular function parameters; 2) increased fractional excretion of Na+ , K+ , and water; 4) proteinuria and increased urinary γ-glutamyl transferase activity (a marker of tubular injury) accompanied by acute tubular necrosis; 5) an increased renal angiotensin-converting enzyme and bradykinin B1 receptor mRNA expression. Interestingly, the preconditioning by moderate-intensity aerobic exercise attenuated all alterations observed in gentamicin-induced AKI (T+AKI group). Taken together, our results show that the preconditioning by moderate-intensity aerobic exercise ameliorates the development of gentamicin-induced AKI. Our findings help to expand the current knowledge regarding the effect of physical exercise on kidneys during physiological and pathological conditions. [ABSTRACT FROM AUTHOR]

The prediction of one-repetition maximum (1RM) is highly relevant for strength and conditioning. The optimal minimum-velocity threshold (MVT) was recently proposed to increase the accuracy of 1RM predictions. Individual load-velocity profiles (LVP) were obtained in 18 athletes enrolled in recreational soccer. Reliability analyses were computed for all LVP-derived variables. Estimations of 1RM were made based on general (0.3 m.s− 1), pre-individual (mean velocity at 1RM obtained in a preliminary session) and optimal MVT (velocity that eliminates the difference between actual and predicted 1RM, determined in a preliminary session). The accuracy of 1RM predictions was examined using absolute-percent error and Bland-Altman plots. Between-day reliability of the LVP and 1RM was good (intraclass-correlation coefficients – ICCs>0.9 and coefficients of variation – CVs<5%). The individual and optimal MVT reached moderate-to-good reliability (ICCs>0.9 and CVs<10%, respectively). The predictions based on the optimal MVT displayed greater accuracy than those obtained with the individual and general MVT (absolute percent error: 2.8 vs. 5.5 vs. 4.9%, respectively). However, wide limits of agreement (LoA) were found between actual and estimated 1RM using this approach (~15 kg). Data indicate that the optimal MVT provides better estimations of 1RM for the free-weight back squat than the general and the individual MVT. [ABSTRACT FROM AUTHOR]

Background: The foot racing disciplines include sprints, middle distances, and long distances, which vary in terms of intensities, duration of training, and metabolic demands. The aim of our study was to evaluate the differences in morpho-functional parameters describing cardiac remodeling in a large cohort of Olympic athletes practicing the different track subspecialties. Methods: We evaluated 140 track and field (52.1% males, mean age 26.3 ± 4.3 years) Olympic athletes divided into four groups according to the distance performed: Group A (46, 32.9%): 100 and 200 mt; Group B (34, 24.3%): 400 mt; Group C (25, 17.9%): 800, 1500, and 3000 mt; Group D (35, 24.9%): 5000, 10,000 mt, and marathon distance. The athletes underwent a pre-participation screening, which included transthoracic echocardiography and exercise stress testing. Results: In Group A and in Group B, most athletes presented normal cardiac geometry (41/46, 89.1% in Group A and 31/34, 91.2% in Group B, p < 0.0001). Instead, in Groups C and D, more than half presented eccentric cardiac remodeling (13\25, 52% in Group C and 23\35, 65.7% in Group D). No significant differences were found between subspecialties in LVEF (p = 0.587), diastolic function (p = 0.431), and training hours/week (p = 0.078). Conclusions: In conclusion, the presence and extent of cardiac remodeling vary according to the distance of the discipline practiced, with the largest dimensional increase in both left and right ventricles and atria in mid- and long-distance runners and the lowest in sprinters. [ABSTRACT FROM AUTHOR]

Introduction: Physical inactivity and sedentary behavior both increase the risk of chronic disease and mortality. Regular participation in physical activity and reducing sedentary behavior play important roles in maintaining physical health and disease prevention. Objective: The purpose of this study was to investigate the effect of programed walking exercise using a wearable hip exoskeleton, Bot Fit on muscle strength, muscle effort, and the kinematics of the pelvis in younger adults. Methods: We designed three parallel experimental conditions and randomly assigned participants to one of three groups: those assigned to exercise using an interval program of Bot Fit (interval group), those who used a power program of Bot Fit (power group), and a control group who exercised without Bot Fit. A total of 45 young adults participated in 18 exercise-intervention sessions over six weeks, and all participants were assessed at two time points: before and after the 18 exercise sessions. Each assessment evaluated muscle strength, muscle effort, and the kinematics of the pelvis during walking. In addition, the number of steps, distance, energy expenditure, and heart rate for 30 min during the exercise sessions were recorded. Results: A significant increase in the maximum voluntary contraction (MVC) of the left biceps femoris (BF) was evident in the interval group, while significant changes in the MVC of the bilateral BF were seen in the power group after Bot Fit exercise. A significant decrease of muscle effort in the right BF in the interval group and right lumbar erector spinae and bilateral BF in the power group were also observed. In addition, the symmetry index of pelvic tilt significantly improved in the interval group, and greater exercise volume and intensity in both the interval and power groups compared with the control group were confirmed as measured by the number of steps, distance, energy expenditure, and heart rate. Conclusions: The results of this study confirmed the beneficial effect of programed walking exercise using the Bot Fit on muscle strength of trunk and lower extremities, muscle effort, and pelvic movement symmetry in younger adults. Personalized exercise programs can be provided for younger adults using various resistance or assistance modes of robotic device with the Bot Fit. Trial Registration: ClinicalTrials.gov, NCT05862077. Registered 22 March 2022, https://register.clinicaltrials.gov/. Key Points: • Bot Fit exercise offers several key advantages over exercise without a Bot Fit in terms of muscle strength, muscle effort, and pelvic symmetry during walking in younger adults. • Greater exercise volume and intensity in interval and power groups who exercised with Bot Fit were confirmed through number of steps, distance, energy expenditure, and heart rate compared to control group who exercised without Bot Fit. [ABSTRACT FROM AUTHOR]

Objective To compare the effects of two exercise intensities on metabolic syndrome (MS). Methods Forty-nine MS patients hospitalized in Taiyuan Central Hospital from December, 2022 to January 2024 were selected and randomly divided into two groups : a standard group (n = 24) and individual group (n = 25). All patients underwent cardiopulmonary exercise test ( CPET) before and after treatment, collecting major indexes including body parameter, body component, and metabolic indicator for prescribing exercise programs. The standard group was trained with exercise intensity prescribed on heart rate reserve, while the individual group received the exercise with intensity prescribed on ventilatory threshold. Both groups received equal energy consumption exercise intervention with the same exercise frequency for 12 weeks. Results The two groups demonstrated significant improvements in waist circumference (WC), body mass index (BMI), body fat related indexes, and systolic blood pressure after intervention (P < 0.05). The individual group showed significant improvements inWC, BMI and body fat related indexes as compared to the standard group (P < 0.05). Both groups showed significant improvements in peak oxygen uptake, (PeakVO2), peak load power (Peak WR), peak metabolic equivalent (PeakMets), and peak respiratory exchange ratio ( Peak RER ) after intervention (P < 0.05 ). The individual group presented significant improvements in peak heart rate (HRpeak), peak oxygen pulse (Peak VO2/HR), and maximum voluntary ventilation (MVV) (P < 0.05) after intervention. Before intervention, the standard group demonstrated significantly higher levels in PeakVO2 and Peak MET compared to the individual group (P < 0.05), but after intervention the two groups showed no significant differences in the two indexes. After the intervention, the individual group demonstrated insignificant improvements in all indexes compared to the standard group (P > 0.05). Conclusions Both exercise prescriptions based on CPET can effectively improve the health-related indicators of MS patients on condition of moderate exercise intensity. However, the program prescribed based on individualized ventilatory threshold shows superiority to the program prescribed based on maximum physiological value in improving these indicators. [ABSTRACT FROM AUTHOR]

Background: Higher prevalence rates of diabetes and its complications have been reported among individuals with poor physical activity and a sedentary lifestyle. This study explored the influence of six months of moderate-intensity supervised aerobic training on the serum lipid profile, hs-CRP level, and variable-related correlations in prediabetic and type 2 diabetes patients (T2DM). Design: The study was based on a two-arm parallel group pretest‒posttest comparative design. Methods: A total of 50 subjects who were diagnosed with diabetes for more than five years and aged 30–70 years were included in this study. The subjects were classified into two groups on the basis of their glycated haemoglobin (HbA1c%) values: Group 1 (patients with the prediabetes; HbA1c % ≤ 6.5, n = 25) and Group 2 (patients with the T2DM; HbA1c % ≥ 6.5, n = 25). Blood sugar, HbA1c %, insulin, lipid profile, and highly sensitive CRP (hs-CRP) were measured via colorimetric and immunoassay techniques at baseline and six months postintervention with moderate aerobic exercise. Results: The results revealed that participation in moderate aerobic training interventions for six months resulted in a significant reduction in BMI, fasting blood sugar, glycosylated haemoglobin, hs-CRP, and lipid profile parameters such as T-Cholest, TG, and LDL-C as well as significant improvement in the level of insulin with a reduction in the values of HOMA-IR towards normal values in the patients with prediabetes (P < 0.01) in group 1 and patients with diabetes in group 2 (P < 0.001). The change in VO2max with good physical fitness significantly improved with the exercise program after six months. The reduced levels of hs-CRP, HOMA-IR, and lipid profile and improved levels of insulin were significantly positively correlated with the levels of glycated haemoglobin (HbA1c%) in the patients with prediabetes (P < 0.01) and those with diabetes (P < 0.001) following six months of moderate aerobic training interventions. Moreover, hs-CRP was positively correlated with T-Cholest, TG, and LDL-C (p = 0.01) and negatively correlated with HDL-C. The data revealed improved glycemic control factors, lipid profiles, and hs-CRP levels as cardio-predictive markers in patients with both prediabetes and diabetes as well. These findings suggest that the anti-inflammatory effect of physical activity gained from moderate exercise training for six months may counteract increased cardiovascular complications associated with increased CRP levels and lipid profiles in prediabetes and T2DM patients. Conclusions: Moderate aerobic training for six months favourably affects glycemic parameters, lipid profiles, and inflammatory hs-CRP indicators and improves VO2max, an indicator of physical fitness, in prediabetic and diabetic patients. The data obtained suggest the positive effect of moderate exercise training as a protective modulator of cardiovascular disorders, including the dyslipidaemic profile, glycaemic control, and hs-CRP inflammatory markers, in prediabetes and T2DM patients. Thus, regular exercise, owing to its anti-inflammatory effects and ability to improve cardiorespiratory fitness, lipid profiles, blood glucose levels, and insulin resistance, may help reduce the severity of cardiovascular diseases in prediabetes and T2DM patients and healthy controls. Trial registration: Retrospectively registered with ClinicalTrials.gov PRS under trial identifier ID: NCT06246435 dated 30/01/2024. [ABSTRACT FROM AUTHOR]

This paper concerns an age-structured juvenile-adult model incorporating harvesting pulse and moving boundaries in a heterogeneous environment, in which harvesting reflects human periodic pulse intervention on adults and the moving boundaries describe the natural expanding front of species. The principal eigenvalue is firstly defined and its properties involving the intensity of harvesting and length of habitat sizes are analyzed. Then the criteria to determine whether the species spread or vanish is discussed, and some relevant sufficient conditions characterized by pulse are established. Our results reveal that the co-extinction or coexistence of species is influenced by internal expanding capacity from species itself and external harvesting pulse from human intervention, in which the intensity and timing of harvesting play key roles. Our numerical simulations validate that the larger the harvesting rate and the shorter the harvesting period, the worse the survival of the species due to the cooperation among juveniles and adults, and such harvesting pulse can even alter the situation of species from persistence to extinction. In addition, expanding capacities also affect or alter the outcomes of spreading and vanishing. [ABSTRACT FROM AUTHOR]

Introduction: Overuse musculoskeletal injuries (MSKI) remain a significant medical challenge in military personnel undergoing military training courses; further understanding of the biological process leading to overuse MSKI development and biological signatures for injury risk are warranted. The purpose of this study was to determine the association between overuse MSKI occurrence and physiological characteristics of allostatic load characterized as maladaptive biological responses to chronic stress measured by wearable devices in USMarine Corps officer candidates during a 10-wk training course. Methods: Devices recorded energy expenditure (EE), daytime heart rate (HR), sleeping HR, and sleep architecture (time and percentage of deep, light, rapid eye movement sleep, awake time, total sleep). Flux was calculated as the raw or absolute difference in the average value for that day or night and the day or night beforehand. Linear mixed-effect model analysis accounting for cardiorespiratory fitness assessed the association between overuse MSKI occurrence and device metrics (a = 0.05). Results: Sixty-nine participants (23 females) were included. Twenty-one participants (eight females) sustained overuse MSKI. Overuse MSKI occurrence in male participants was positively associated with daytime HR (ß = 5.316, P = 0.008), sleeping HR (ß = 2.708, P = 0.032), relative EE (ß = 8.968, P = 0.001), absolute flux in relative EE (ß = 2.994, P = 0.002), absolute EE (ß = 626.830, P = 0.001), and absolute flux in absolute EE (ß = 204.062, P = 0.004). Overuse MSKI occurrence in female participants was positively associated with relative EE (ß = 5.955, P = 0.026), deep sleep time (ß = 0.664, P < 0.001), and percent deep sleep (ß = 12.564, P < 0.001) and negatively associated with absolute flux in sleeping HR (ß = -0.660, P = 0.009). Conclusions: Overuse MSKI occurrences were associated with physiological characteristics of allostatic load, including chronically elevated HR and EE and greater time in restorative sleep stages, whichmay serve as biological signatures for overuse MSKI risk. [ABSTRACT FROM AUTHOR]

Purpose: This study reports the results of a 20-yr (2005 to 2024) follow-up study of two 2-time Olympic and 6-time world champion rowing athletes. To provide a comprehensive picture of adaptations in physiological and performance characteristics to long-term training, we monitored the athletes' physiological and performance data annually through five 4-yr developmental phases. Methods: Maximal oxygen uptake (VO2max), maximal minute power (MMP), and power output corresponding to anaerobic threshold (PAT) were derived from a rampwise exercise test on a rowing ergometer. In addition, average power output sustained during all-out tests over 2000 and 6000 m on a rowing ergometer was also obtained. Results: VO2max peaked at age 22 for athlete A and at age 25 for athlete B (at ~7 L·min-1) before stabilizing and then gradually declining to a range of 6.2 to 6.5 L·min-1 for both athletes. MMP stabilized in both rowers at values between 550 and 575Wand displayed minimal fluctuations over the final two phases of the study. In addition, MMP closely resembled the corresponding average power output sustained during the 2000-m all-out tests on a rowing ergometer. Average power output during 2000 and 6000-m all-out tests showed steady improvements over the monitored phases of the study, with the highest power output crew averages for both 2000-m (532 W; 5 min 48 s) and 6000-m (463 W; 18 min 4 s) tests recorded during the last 4-yr phase of the assessment. Conclusions: Improvements in rowing ergometer performance over 2000 and 6000 m appear to be largely independent of the multiyear changes in VO2max. Long-term rowing training resulted in continuous improvements inMMP and PAT throughout the monitored phases, which more closely mimicked improvements in rowing ergometer performance. [ABSTRACT FROM AUTHOR]

Understanding muscle activation during exercises is crucial for devising effective training programs. We examined correlations between self-reported and electromyographic (EMG) muscle activity during upper-body exercises performed at loads corresponding to 4-6 repetition maximums (RMs). Thirteen male sub-elite soccer players who had previously engaged in resistance training participated in two testing sessions. In the initial session, the loads corresponding to 4–6 repetitions were determined for six exercises: Lat Pull Down (LPD), Barbell Bent Over Row (BBOR), Dumbbell Row (DR), Barbell Pull Over (BPO), Dumbbell Reverse Fly (DRF), and Dumbbell Concentration Curl (DCC). At post-exercise, participants rated their perceived muscle activation for three targeted muscles in each exercise on a 1–10 point Likert scale (LS). In the subsequent session, we used EMG to measure the activity of eight agonist and synergist muscles during these exercises. We found that one of two synergist muscles consistently demonstrated higher activity levels. Interestingly, we observed no difference in activity between primary and secondary (or synergist) muscles across all exercises. Most importantly, we found no significant correlation between the perceived muscle activation rate and the EMG measured activation level for any exercise. In conclusion, our findings suggest that, despite differential muscle activity during specific exercises, self-reported muscle activation may not accurately correspond to actual muscle activation, as measured via EMG, due to the participants' poor interoceptive awareness of muscles. These data highlight the potential limitations of relying on perceived muscle activation as a sole gauge of training intensity. [ABSTRACT FROM AUTHOR]

Our objective in this study was to investigate the effect of moderate-intensity aerobic exercise on visuospatial attention bias. We examined line bisection performance at rest before exercise and then immediately after exercise in 20 young adults. Pre-exercise, there was a larger leftward bias in subjective midpoint judgment of all participants than post-exercise (p <.001). Thus, leftward error magnitude decreased according to aerobic exercise, as there were rightward shifts after the exercise. The participants' performances were modulated by the hand used to perform manual bisection tasks (p <.02). Participants erred to the left of the true midpoint with the non-dominant hand and to the right of the true midpoint with the dominant hand. The use of the non-dominant hand led to greater leftward error than the errors obtained using the dominant hand, though there was no interaction effect between hand use and effort. These findings suggest that moderate aerobic exercise can benefit visuospatial attention in adults. [ABSTRACT FROM AUTHOR]

Introduction: Maternal overweight or obesity has been associated with metabolic syndrome through 1 year postpartum, but it remains unknown whether a culturally-modified, motivationally-targeted, and individually-tailored Lifestyle Intervention could improve postpartum cardiometabolic health among Hispanic women with overweight or obesity. Methods: Proyecto Mamá was a randomized controlled trial conducted in Western Massachusetts from 2014 to 2020 in which Hispanic women with overweight/obesity were randomized to a Lifestyle Intervention (LI) involving diet and exercise or to a comparison Health and Wellness Intervention (HW). Biomarkers of cardiovascular risk (i.e., lipids, C-reactive protein) and insulin resistance (fasting insulin, glucose, HbA1c, homeostasis model assessment [HOMA-IR], leptin, adiponectin) were measured at baseline (early pregnancy), mid-pregnancy, and 6 weeks, 6 months, and 12 months postpartum. Generalized linear mixed effect models were used to evaluate differences in the change in biomarkers over the course of postpartum follow-up time. Results: In intent-to-treat analyses among eligible women (LI; n=51, HW; n=58) there were no significant differences in changes in biomarkers of CVD risk or insulin resistance over the postpartum year; for example, the intervention effect for total cholesterol was 6.98 (SE: 6.36, p=0.27) and for HbA1c was −0.01 (SE: 0.4, p=0.85). In pooled analyses, regardless of intervention arm, women who participated in any vigorous activity had less of an increase in HbA1c (intervention effect = −0.17, SE: 0.05, p=0.002) compared to those with no vigorous activity, and similarly beneficial associations with other cardiovascular risk biomarkers (p<0.05). Discussion: Women who participated in vigorous activity, regardless of their assigned intervention arm, had more favorable changes in biomarkers of insulin resistance. Significance: Women with overweight/obesity during pregnancy are at an increased risk of adverse cardiometabolic profiles and future development of type 2 diabetes and cardiovascular disease. Hispanic women are disproportionately affected by cardiometabolic disorders but have largely been excluded from lifestyle intervention studies. Although providing a lifestyle intervention to Hispanic women with overweight/obesity resulted in no significant differences in postpartum cardiometabolic biomarkers, women who articipated in vigorous activity, regardless of their assigned intervention arm, had favorable changes in insulin resistance biomarkers. These findings suggest that the intensity of physical activity may be important for improving postpartum cardiometabolic biomarkers among high-risk, Hispanic women. [ABSTRACT FROM AUTHOR]

Objective This study investigated the effectiveness of supramaximal high-intensity interval training (supramaximal HIT) on muscle capacities and physical function compared to moderate-intensity training (MIT) for older adults. Methods Sixty-eight older adults (66–79 years, 56% women), not engaged in regular exercise, were randomised to 3 months of twice-weekly supramaximal HIT (20 minutes including 10 × 6-second intervals) or MIT (40 minutes including 3 × 8-minute intervals). Both groups performed the training on stationary bicycles in a group setting. Target intensity was watt-controlled, with standardised cadence and individualised resistance. Outcomes analysed with linear-mixed models included leg power (Nottingham Power Rig), hand grip strength (Jamar dynamometer), static and dynamic balance (One leg stance, 30-second step test), chair stand (30-second chair stand), and anaerobic cycling performance (modified Borg Cycle Strength Test). Results Baseline values were (supramaximal HIT/MIT, mean ± SD) leg power 198 ± 60/189 ± 53 W, hand grip strength 4.2 ± 1.0/4.3 ± 1.1 N/kg, static balance 64 ± 41/62 ± 41 s, dynamic balance 39 ± 7/38 ± 5 steps, chair stands 22 ± 6/22 ± 6 and anaerobic cycling performance 224 ± 60/217 ± 55 W. At 3-month follow-up, a between-group difference in favour of supramaximal HIT [95% CI] was observed in anaerobic cycling performance of 19[3;35] W. Within-group mean changes for supramaximal HIT/MIT were for leg power 8.4[0.9;15.8]/6.0[−1.3;13.3] W, hand grip strength 0.14[0.00;0.27]/0.13[−0.01;0.26] N/kg, static balance 11[3;20]/10[1;18] s, dynamic balance 1.6[0.3;2.8]/2.3[1.1;3.6] steps, 2.1[1.1;3.1]/1.4[0.4;2.3] chair stands and anaerobic cycling performance 31.3[19.6;43.0]/12.0[0.4;23.5] W. Conclusion Supramaximal HIT showed superior effect on anaerobic cycling performance when compared to MIT. Additionally, the results indicate that supramaximal HIT is comparably beneficial as MIT in terms of effects on muscle capacity and physical function for older adults. [ABSTRACT FROM AUTHOR]

Objectives We assessed the effects of different exercise modalities and doses on depression levels in older adults. Methods Systematic searches of the PubMed, Web of Science, Embase, PsycINFO, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Scopus databases were conducted from the start of database construction until December 2023. Studies were included if they were randomised controlled trials (RCTs) of exercise interventions in older adults. Pairwise, network and dose-network meta-analyses were conducted using random-effects models for the outcome of depression in older adults. Results A total of 80 RCTs with 5536 participants were included in this study. Network meta-analyses showed that resistance exercise [standardized mean difference (SMD) = − 0.68, 95% confidence interval (CI): − 0.90, − 0.46] and mind–body exercise (MBE; SMD = − 0.54, 95% CI: − 0.72, − 0.37) were the most effective forms of exercise for improving depression in older adults, followed by aerobic exercise (SMD = − 0.31, 95% CI: − 0.50, − 0.13) and mixed exercise (SMD = − 0.23, 95% CI: − 44, − 0.01). In addition, a U-shaped dose–response relationship was found between overall exercise dose and depression levels in older adults, and a significant response was seen after 390 metabolic equivalent (MET)-min/week. Conclusions Our study determined the effectiveness of different exercises in improving levels of older adults and found that resistance exercise and MBE were more effective adjunctive treatments. By providing the most effective treatments, older adults can reap the benefits of improving depression in older adults at doses lower than the World Health Organization guidelines. [ABSTRACT FROM AUTHOR]

Sedentary lifestyles reduce muscle mass, strength, power, and alter viscoelastic properties. Plyometric jump training (PJT) shows promise in countering these effects, but the optimal training volume for individuals with low athletic performance remains unclear. This study aimed to determine the minimal PJT volume required to improve muscle and tendon viscoelastic properties, strength, and power in sedentary individuals. A double-blind randomised controlled trial included 44 participants divided into three groups: Control Group (CG) (n = 16), Reduced Volume Training Group (RVTG) (n = 16), and Training Group (TG) (n = 12). The four-week PJT programme involved three weekly sessions with gradual volume increments; RVTG performed 50% less volume than TG. Baseline and follow-up assessments included the isokinetic standing up (SU) and sitting down (SD) phases at 15 cm/s and 5 cm/s, and myotonometer measurements. In the SU phase at 15 cm/s, significant differences were found (p = 0.01) with higher values in TG (10.0 ± 3.3 N/kg) compared to CG and RVTG. At 5 cm/s, differences in SD were observed (p = 0.002). For Achilles tendon properties in RVTG: stiffness (p = 0.04), decrement (p = 0.01), and relaxation (p = 0.02). A PJT volume of 2,414 jumps improved muscle strength, while 1,207 jumps altered tendon properties. [ABSTRACT FROM AUTHOR]

Introduction: The effects of breaking up sitting on gut hormone responses and free-living energy compensatory behaviors are still unclear in people of Asian ethnicity. Methods: Twenty-six Asians including 13 lean individuals (Lean) and 13 individuals with centrally overweight/obesity (OW), aged between 20 and 45 yr, completed a randomized crossover study with either 5.5-h uninterrupted sitting (SIT) or 5.5-h sitting with 2-min walking at 6.4 km·h−1 every 20 min (ACTIVE) in the laboratory. Blood samples were collected at regular time points to examine postprandial glucagon-like peptide 1 (GLP-1), peptide YY (PYY), and glucose-dependent insulinotropic polypeptide (GIP) concentrations. Free-living physical activity and energy intake were recorded using wearable devices and weighed food diaries outside the laboratory until midnight. Paired t-tests were conducted to compare responses between trials. Results: Postprandial GLP-1 and PYY incremental area under the curve values were higher in the ACTIVE trial versus SIT in both Lean and OW groups (all, P < 0.05), but there was no difference in GIP in either group (both, P > 0.05). There were no differences in free-living physical activity (volume and intensity) or energy intake (total and macronutrients) between trials in either group (all, P > 0.05), resulting in greater total physical activity over the 24-h monitoring period in ACTIVE trial versus SIT trial (both, P < 0.05). Conclusions: Breaking up sitting increases postprandial GLP-1 and PYY concentrations in Asians, but does not induce subsequent behavioral compensation, resulting in greater 24-h physical activity levels and lower relative energy intake, in inactive individuals irrespective of bodyweight status. [ABSTRACT FROM AUTHOR]

Purpose: Ventilatory constraints are common during exercise in children, but the effects of obesity and sex are unclear. The purpose of this study was to investigate the effects of obesity and sex on ventilatory constraints (i.e., expiratory flow limitation (EFL) and dynamic hyperinflation) during a maximal exercise test in children. Methods: Thirty-four 8- to 12-yr-old children without obesity (18 females) and 54 with obesity (23 females) completed pulmonary function testing and maximal cardiopulmonary exercise tests. EFL was calculated as the overlap between tidal flow–volume loops during exercise and maximal expiratory flow–volume loops. Dynamic hyperinflation was calculated as the change in inspiratory capacity from rest to exercise. Results: Maximal minute ventilation was not different between children with and without obesity. Average end-inspiratory lung volumes (EILV) and end-expiratory lung volumes (EELV) were significantly lower during exercise in children with obesity (EILV: 68.8% ± 0.7% TLC; EELV: 41.2% ± 0.5% TLC) compared with children without obesity (EILV: 73.7% ± 0.8% TLC; EELV: 44.8% ± 0.6% TLC; P < 0.001). Throughout exercise, children with obesity experienced more EFL and dynamic hyperinflation compared with those without obesity (P < 0.001). Also, males experienced more EFL and dynamic hyperinflation throughout exercise compared with females (P < 0.001). At maximal exercise, the prevalence of EFL was similar in males with and without obesity; however, the prevalence of EFL in females was significantly different, with 57% of females with obesity experiencing EFL compared with 17% of females without obesity (P < 0.05). At maximal exercise, 44% of children with obesity experienced dynamic hyperinflation compared with 12% of children without obesity (P = 0.002). Conclusions: Obesity in children increases the risk of developing mechanical ventilatory constraints such as dynamic hyperinflation and EFL. Sex differences were apparent with males experiencing more ventilatory constraints compared with females. [ABSTRACT FROM AUTHOR]

Purpose: Exercise benefits the body and mind, but its weight loss effect is less than generally expected. Although this phenomenon is likely due to an exercise intensity–dependent decrease in non-exercise physical activity (NEPA), resulting in a decrease in non-exercise activity thermogenesis, the underlying mechanisms and effects of exercise intensity remain unknown. Here we show that acute vigorous exercise decreases subsequent NEPA and body temperature (BT) in association with body weight gain. Methods: Adult male C57BL/6J mice were categorized into three groups: sedentary, moderate exercise, and vigorous exercise, with exercise groups undergoing a 30-min treadmill session. Using an intraperitoneally implanted activity monitor, NEPA and BT were monitored for 2 d before and 3 d after exercise. The daily synchrony between NEPA and BT was evaluated using a cross-correlation function. Plasma corticosterone was also detected 6 and 24 h after exercise. Results: Notably, only the vigorous exercise group exhibited a decline in both NEPA and BT, resulting in body weight gain the following day, despite no observed changes in food intake. Furthermore, vigorous exercise induces a distinct delay in the daily dynamics of NEPA compared with BT. A positive correlation was observed between plasma corticosterone levels and changes in NEPA levels before and after exercise across all exercise groups. Conclusions: Our findings provide evidence for vigorous exercise–specific reduction in subsequent NEPA, BT, and their synchrony linked to weight gain, likely due to the disturbed circadian rhythm of corticosterone. This is an initial investigation redefining the significance of exercise intensity in beneficial effects beyond the energy expenditure of the exercise itself [ABSTRACT FROM AUTHOR]

Introduction: Children’s anxiety is associated with decreased cognitive performance. One well-established behavioral intervention to transiently improve cognitive performance in children is acute aerobic exercise (AAE). Thus far, however, it is unclear whether the benefits of AAE on cognition vary based on individual differences in children’s anxiety level. Therefore, we investigated whether trait anxiety levels mediate the effects of AAE on cognitive outcomes in preadolescent children. Methods: Ninety-five preadolescent children (9 to 11 yr, 41 females) underwent two experimental interventions in a random, crossover, and counterbalanced design: an exercise protocol (20 min of walking at 65% to 75% of HRpeak) and a nonexercise control (seated rest). Behavioral indices of cognitive performance (accuracy, reaction times, response time (RT) variability) were assessed before and after each intervention using a modified flanker task. The effects of each intervention on cognitive performance were calculated as pre- to postintervention differences (effect scores). These scores were first correlated with children’s personal characteristics: anxiety (STAIC), sex, age, body mass index, intelligence quotient, and aerobic fitness. Significant correlations guided subsequent hierarchical regression models, which specifically tested for associations between the effects scores and anxiety levels while controlling for remaining relevant covariates. Results: Regression analysis revealed that anxiety was a significant predictor of the effects that AAE and rest had on cognitive performance. Specifically, higher anxiety scores were associated with greater exercise-induced cognitive benefits (increased accuracy, decreased RT variability; all P < 0.05) and greater rest-induced cognitive impairments (decreased accuracy, increased RT variability; all P < 0.01). Conclusions: These findings suggest that children reporting higher trait anxiety might experience greater cognitive benefits from a single bout of AAE. [ABSTRACT FROM AUTHOR]

Before examining the impact of training load on injury risk in runners, it is important to gain insight into the differences between methods that are used to measure change in training load. To investigate differences between 4 methods when calculating change in training load: (1) weekly training load; (2) acute : chronic workload ratio (ACWR), coupled rolling average (RA); (3) ACWR, uncoupled RA; (4) ACWR, exponentially weighted moving average (EWMA). Descriptive epidemiology study. This study is part of a randomized controlled trial on running injury prevention among recreational runners. Runners received a baseline questionnaire and a request to share global positioning system training data. Runners who registered for running events (distances 10–42.195 km) in the Netherlands. The primary outcome measure was the predefined significant increase in training load (weekly training loads ≥ 30% progression and ACWRs ≥ 1.5), based on training distance. Proportional Venn diagrams visualized the differences between the methods. A total of 430 participants (73.3% men; mean age = 44.3 ± 12.2 years) shared their global positioning system training data for a total of 22 839 training sessions. For the weekly training load, coupled RA, uncoupled RA, and EWMA method, respectively, 33.4% (95% CI = 32.8, 34.0), 16.2% (95% CI = 15.7, 16.6), 25.8% (95% CI = 25.3, 26.4), and 18.9% (95% CI = 18.4, 19.4) of the training sessions were classified as significant increases in training load. Of the training sessions with significant increases in training load, 43.0% from the weekly training load method were different than the coupled RA and EWMA methods. Training sessions with significant increases in training load based on the coupled RA method showed 100% overlap with the uncoupled RA and EWMA methods. The difference in the change in training load measured by weekly training load and ACWR methods was high. To validate an appropriate measure of change in training load in runners, future research on the association between training loads and running-related injury risk is needed. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the difference in head acceleration event (HAE) incidence between training and match‐play in women's and men's players competing at the highest level of domestic rugby union globally. Players from Women's (Premiership Women's Rugby, Farah Palmer Cup) and Men's (Premiership Rugby, Currie Cup) rugby union competitions wore instrumented mouthguards during matches and training sessions during the 2022/2023 seasons. Peak linear (PLA) and angular (PAA) acceleration were calculated from each HAE and included within generalized linear mixed‐effects models. The incidence of HAEs was significantly greater in match‐play compared to training for all magnitude thresholds in both forwards and backs, despite players spending approximately 1.75–2.5 times more time in training. For all HAEs (PLA > 5 g and PAA > 400 rad/s2), incidence rate ratios (IRRs) for match versus training ranged from 2.80 (95% CI: 2.38–3.30; men's forwards) to 4.00 (3.31–4.84; women's forwards). At higher magnitude thresholds (PLA > 25 g; PAA > 2000 rad/s2), IRRs ranged from 3.64 (2.02–6.55; PAA > 2000 rad/s2 in men's backs) to 11.70 (6.50–21.08; PAA > 2000 rad/s2 in women's forwards). Similar trends were observed in each competition. Players experienced significantly more HAEs during match‐play than training, particularly at higher magnitude thresholds. Where feasible, HAE mitigation strategies may have more scope for HAE reduction if targeted at match‐play, particularly where higher magnitude HAEs are the primary concern. However, the number of HAEs associated with different training drills requires exploration to understand if HAEs can be reduced in training, alongside optimizing match performance (e.g., enhancing contact technique). [ABSTRACT FROM AUTHOR]

This analysis aimed to (1) identify longitudinal joint trajectories of participation in organized and unorganized physical activity contexts, and level of daily moderate‐to‐vigorous physical activity (MVPA) and (2) assess whether basic psychological need satisfaction during adolescence differentiates between membership in different physical activity trajectories. Participants (n = 888; 56% girls) reported their involvement in 36 different physical activities, level of MVPA, and their perceived satisfaction of competence, autonomy, and relatedness satisfaction in physical activity up to three times per year, over 8 years (from ages 10 to 17 years). Group‐based multi‐trajectory models were used to identify longitudinal joint trajectories of physical activity participation. We estimated a multinomial logistic regression model for membership in a physical activity trajectory by including individual‐level intercepts and slopes for each psychological need obtained using mixed models over the 24 cycles modelized as natural cubic splines. Five longitudinal trajectory groups emerged: Non‐participants, Dropouts, Active in unorganized physical activities, Active in organized physical activities, and Active through a variety of activities. Relative to Non‐participants, we identify a dose–response relationship in baseline competence and membership in the higher active trajectory groups. In addition, a positive change in competence in early adolescence predicted membership in all three Active trajectory groups. [ABSTRACT FROM AUTHOR]

It is not clear if fat oxidation is attenuated at higher exercise intensities, when exercising with a small muscle mass, and therefore, we studied leg fat oxidation during graded one‐leg exercise. Ten males (age: 27 ± 2 years, body mass: 82 ± 3 kg, BMI: 24 ± 1 kg m−2, V̇O2max: 49 ± 2 mL min−1 kg−1) performed one‐leg exercise at 25% of maximal workload (Wmax) for 30 min, followed by 120‐min exercise at 55% Wmax with the contralateral leg, and finally 30‐min exercise at 85% Wmax with the first leg. Blood was sampled from an artery and both femoral veins, and blood flow was determined using Doppler ultrasound. Muscle biopsies were obtained before and after 30 min at each workload. One‐way RM ANOVA was applied to determine the impact of exercise intensity. Data are expressed as mean ± SEM. From rest through exercise average blood flow (0.4 ± 0.1, 2.1 ± 0.1, 2.6 ± 0.2, 3.7 ± 0.2 L min−1) and oxygen uptake across the leg (0.03 ± 0.01, 0.23 ± 0.02, 0.35 ± 0.03, 0.53 ± 0.04 L min−1) increased with exercise intensity (p < 0.001). Leg RQ (0.76 ± 0.04, 0.86 ± 0.02,0.87 ± 0.01, 0.92 ± 0.01, p < 0.001), leg plasma FA uptake (2 ± 2, 46 ± 8,83 ± 9, 114 ± 16 μmol min−1; p < 0.001) and rate of leg fat oxidation (0.016 ± 0.005, 0.062 ± 0.012, 0.075 ± 0.011, 0.084 ± 0.018 g min−1, p < 0.007) increased with exercise intensity. Muscle‐free carnitine content was unchanged from rest at 25% Wmax and decreased after 30 min exercise at 55% and 85% Wmax (17.4 ± 1.6, 16.6 ± 0.7, 14.5 ± 1.2, 10.5 ± 1.0 mmol/kg dry muscle, respectively; p < 0.006). During incremental one‐leg exercise, the rate of leg fat oxidation was not attenuated with increasing exercise intensity, probably due to an insufficient muscle metabolic stress response. [ABSTRACT FROM AUTHOR]

The aim was to determine the validity and test – retest reliability of the Sit to Stand App variables (rising time, vertical velocity, and power) for measuring single-leg sit-to-stand (STS) test compared to those derived from ground reaction force data. Twenty-seven female athletes performed the single-leg STS test over three consecutive sessions simultaneously recorded with a force plate and the smartphone app. Validity was assessed with Pearson's correlation coefficient, intra-class correlation coefficient (ICC), and percentage error. Reliability was assessed with the ICC. Almost perfect correlations (r ≥ 0.95) and excellent agreement (ICC = 0.96–0.97) between the app and force plate measures with low percentage errors (≤7.3%) were found. The app showed good-to-excellent reliability (ICC = 0.88–0.92) with no differences in inter-limb asymmetry over three sessions. The app was highly valid and reliable for measuring single-leg STS performance. Practitioners can use this app to assess lower-limb performance in female athletes. [ABSTRACT FROM AUTHOR]

Background and Objectives: Few comparative studies have evaluated wearable single-lead electrocardiogram (ECG) devices and standard multi-lead ECG devices during exercise testing. This study aimed to validate the accuracy of a wearable single-lead ECG monitor for recording heart rate (HR) metrics during graded exercise tests (GXTs). Methods: A cohort of 50 patients at a tertiary hospital underwent GXT while simultaneously being equipped with wearable single- and conventional multi-lead ECGs. The concordance between these modalities was quantified using the intraclass correlation coefficient and Bland–Altman plot analysis. Results: The minimum and average HR readings between the devices were generally consistent. Parameters such as ventricular ectopic beats and supraventricular ectopic beats showed strong agreement. However, the agreement for the Total QRS and Maximum RR was not sufficient. HR measurements across different stages of the exercise test showed sufficient agreement. Although not statistically significant, the standard multi-lead ECG devices exhibited higher noise levels compared to the wearable single-lead ECG devices. Conclusions: Wearable single-lead ECG devices can reliably monitor HR and detect abnormal beats across a spectrum of exercise intensities, offering a viable alternative to traditional multi-lead systems. [ABSTRACT FROM AUTHOR]

This study compared cardiovascular and metabolic responses during concentric and eccentric stepping. Eight participants (5 m, 3f; 22 ± 2 years) performed maximal concentric and eccentric ramp incremental tests on a modified stepping ergometer. Subsequently, three randomized 15‐min constant‐power tests were performed (1) concentric stepping at 90% of the concentric lactate threshold (LT), (2) eccentric stepping at the same power, and (3) eccentric stepping at the same oxygen uptake (V̇O2). At equivalent power (36 ± 6 W, p = 0.62), eccentric stepping resulted in 46 ± 8% lower V̇O2, 16 ± 6% lower heart rate (HR), and 11 ± 5% lower mean arterial blood pressure compared to concentric (p < 0.01). Matching V̇O2 required 65 ± 19% more power during eccentric stepping (p < 0.01). During this test, eccentric V̇O2 and HR continued to increase, resulting in a 22 ± 29% higher V̇O2 and 19 ± 16% higher HR in the final minute (p < 0.001). Reduced cardiorespiratory demand during eccentric stepping at the same power as concentric demonstrates a higher eccentric power is required to produce the same V̇O2. However, despite being below the concentric LT, eccentric V̇O2 and HR continued to increase past the predicted steady state, indicating a higher exercise intensity. [ABSTRACT FROM AUTHOR]

Purpose: The perception of effort exerts influence in determining task failure during endurance performance. Training interventions blending physical and cognitive tasks yielded promising results in enhancing performance. Motor imagery can decrease the perception of effort. Whether combining motor imagery and physical training improves endurance remains to be understood, and this was the aim of this study. Methods: Participants (24 ± 3 year) were assigned to a motor imagery (n = 16) or a control (n = 17) group. Both groups engaged in physical exercises targeting the knee extensors (i.e., wall squat, 12 training sessions, 14-days), with participants from the motor imagery group also performing motor imagery. Each participant visited the laboratory Pre and Post-training, during which we assessed endurance performance through a sustained submaximal isometric knee extension contraction until task failure, at either 20% or 40% of the maximal voluntary contraction peak torque. Perceptions of effort and muscle pain were measured during the exercise. Results: We reported no changes in endurance performance for the control group. Endurance performance in the motor imagery group exhibited significant improvements when the intensity of the sustained isometric exercise closely matched that used in training. These enhancements were less pronounced when considering the higher exercise intensity. No reduction in perception of effort was observed in both groups. There was a noticeable decrease in muscle pain perception within the motor imagery group Post training. Conclusion: Combining motor imagery and physical training may offer a promising avenue for enhancing endurance performance and managing pain in various contexts. [ABSTRACT FROM AUTHOR]

Purpose: The aims of the present study were to investigate blood lactate kinetics following high intensity exercise and identify the physiological determinants of 800 m running performance. Methods: Fourteen competitive 800 m runners performed two running tests. First, participants performed a multistage graded exercise test to determine physiological indicators related to endurance performance. Second, participants performed four to six 30-s high intensity running bouts to determine post-exercise blood lactate kinetics. Using a biexponential time function, lactate exchange ability (γ1), lactate removal ability (γ2), and the quantity of lactate accumulated (QLaA) were calculated from individual blood lactate recovery data. Results: 800 m running performance was significantly correlated with peak oxygen consumption (r = −0.794), γ1 and γ2 at 800 m race pace (r = −0.604 and −0.845, respectively), and QLaA at maximal running speed (r = −0.657). V ˙ O2peak and γ2 at 800 m race pace explained 83% of the variance in 800 m running performance. Conclusion: Our results indicate that (1) a high capacity to exchange and remove lactate, (2) a high capacity for short-term lactate accumulation and, (3) peak oxygen consumption, are critical elements of 800 m running performance. Accordingly, while lactate has primarily been utilized as a performance indicator for long-distance running, post-exercise lactate kinetics may also prove valuable as a performance determinant in middle-distance running. [ABSTRACT FROM AUTHOR]