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Purpose: Interval-training sets may be applied in a different sequence within a swimming training session. The aim of this study was to investigate the effect of different set sequences on performance and physiological responses in a training session. Methods: Twelve highly trained male swimmers performed 4 sessions in randomized order. Each session included a different combination of 2 training sets: set A–set C, set C–set A, set B–set C, or set C–set B. Set A consisted of 8 × 200 m at speed corresponding to lactate threshold (30-s recovery), set B included 8 × 100 m at maximum aerobic speed (30-s recovery), and set C included 4 × 50-m all-out swimming (2-min recovery). Performance and physiological responses (lactate concentration, pH, base excess, bicarbonate, heart rate, and heart-rate variability) were measured. Results: Performance in each set was similar between sessions irrespective of set sequence. Blood lactate, heart rate, and acid–base responses during set C were similar in all sessions, but blood lactate was higher in sets A and B during C–A and C–B sessions (P =.01). The overall blood lactate and acid–base response was higher in C–A and C–B sessions compared with A–C and B–C sessions, respectively (P =.01). Heart-rate variability in each set, separately as well as the overall session effect, did not differ and was thus independent to the set sequence applied. Conclusions: Training sessions including all-out swimming as a first set increase the magnitude of metabolic responses to the subsequent aerobic-dominated training set. [ABSTRACT FROM AUTHOR]

Background: In recent years, it has been demonstrated that when the endothelial glycocalyx, composed of proteoglycans, glycosaminoglycans and glycoproteins, is altered or modified, this property is lost, playing a fundamental role in cardiovascular pathologies. Cardiovascular risk factors can destroy the endothelial glycocalyx layer. Exercise has a positive effect on cardiovascular risk factors, but little is known about its direct effect on the integrity of the endothelial layer. Methods: The Cochrane Library, PubMed, Web of Science and Scopus databases were searched from their inception to June 30, 2022. The DerSimonian and Laird method was used to compute pooled effect size estimates and their respective 95% confidence intervals for the acute effect of exercise (within 24 h) on the endothelial glycocalyx and its components in healthy adults. Results: Ten studies were included in the meta‐analysis, with a total of 252 healthy subjects. The types of exercise included were resistance training, interval training, resistance training and maximal incremental exercise, with a duration range of 30–60 min. Glycocalyx assessment times included ranged from 0 to 90 min post‐exercise. Our findings showed that endothelial glycocalyx increases after acute effect of exercise in healthy population (.56, 95% CI:.38,.74). The acute effect of exercise on endothelial glycocalyx components were.47 (95% CIs:.27,.67) for glycosaminoglycans,.67 (95% CIs:.08, 1.26) for proteoglycans and.61 (95% CIs:.35,.86) for glycoproteins. Conclusions: In a healthy population, various types of exercise showed an acute improvement of the endothelial glycocalyx and its individual components. [ABSTRACT FROM AUTHOR]

Purpose: High-intensity long-interval training (long-HIIT; interval ≥ 1 min; intensity 85–100% of maximal oxygen uptake [V̇O2max]) is often applied for cardiorespiratory adaptations; however, long-HIIT can also challenge the anaerobic and neuromuscular systems. Therefore, this study aimed to investigate the effects of 4-week long-HIIT (11 sessions) on anaerobic capacity, repeated sprint ability (RSA), and neuromuscular function. Methods: Twenty active men (V̇O2max: 44.8 ± 5.3 mL.kg−1.min−1) performed an incremental running test (TINC), a supramaximal test consisting in running until the task failure at 115% of maximum velocity achieved in TINC (VINC) for anaerobic capacity determination, and an RSA test (2 × 6 × 35-m all-out sprints) pre- and post-HIIT. Before and after RSA, the neuromuscular function was assessed with counter movement jumps (CMJ) and knee extensors maximal isometric voluntary contractions (MVC) with femoral nerve electrical stimulation. Long-HIIT consisted of 10 × 1-min runs at 90% of VINC with 1-min recovery. Results: Long-HIIT induced significant increase in V̇O2max (P = 0.0001). Although anaerobic capacity did not change significantly, 60% of the participants improved above the smallest worthwhile change (0.2 × standard deviation of pre-HIIT). The changes in sprint performance over RSA was significantly less post-HIIT than pre (P = 0.01). RSA induced significant drop of MVC, high frequency doublet, voluntary activation and CMJ performance at pre- and post-HIIT (P < 0.01); however, the percentage of reduction from rest to fatigued conditions were not significantly altered at post-HIIT compared to Pre. Conclusions: 11 sessions of long-HIIT over 4-week improved maximal aerobic power but not anaerobic capacity, and neuromuscular function. Yet, neuromuscular fatigue was similar despite greater speeds reached during RSA. [ABSTRACT FROM AUTHOR]

This study aimed to examine whether a period of high intensity intermittent training (HIIT) training influences aerobic and anaerobic performance in elite Karate athletes. Sixteen elite karate athletes volunteered to participate in this study. The athletes were randomly and gender-specifically divided into high intensity intermittent training (HIIT) group performed three times/week in addition to normal training for 6 weeks, and a traditional training (TT) group completing regular karate training. Body composition and maximal oxygen consumption as well as muscle power, speed, agility, and anaerobic power variables were assessed before and after the intervention. In addition, the blood lactate levels were measured in rest, after a warm-up period, and immediately, 5, 30, and 60 min after a Wingate test. The level of significance set ρ ≤ 0.05 for the study. A significant difference was observed in VO2max between HIIT and TT groups in post-test (p = 0.006). Furthermore, a significant difference observed between the muscle power (p = 0.001), speed (p = 0.013), agility (p = 0.004), peak power (PP) (p = 0.002), average power (AP) (p = 0.004), VO2max (p = 0.002), and level of the blood lactate concentration 60 min after Wingate test (p = 0.001) in HIIT group from pre- to post-test. A time × group interaction in muscle power (p = 0.001), speed (p = 0.021), and VO2max (p = 0.005) was observed. HIIT positively influences aerobic and anaerobic power in elite karate athletes compared to TT. [ABSTRACT FROM AUTHOR]

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Background: Acute physical activity often induces an acute reduction in pain sensitivity known as exercise induced hypoalgesia (EIH). The aim of this study was to investigate the effects of a high intensity functional training (HIFT) on EIH compared to a control session. Methods: 50 (age: 26.0 ± 2.7; 23 female) participants successfully conducted this study consisting of a pre-experimental test as well as a 12-minute HIFT (body-weight exercises) and a 12-minute control (supervised breathing) session in a randomized crossover design. Pre and post, pressure pain thresholds (PPT) were measured at the ankles, knees, elbows, and forehead. Results: The HIFT resulted in a relative maximum and average heart rate of 96.2% (± 3.6%) and 91.1% (± 4.2%), respectively, and maximum and average RPE values of 19.1 (± 1.2) and 16.2 (± 1.4), respectively. Results reveal a significant 'Intervention' × 'Time point' interaction (p < 0.001) for PPT (pooled for one average value) with hypoalgesia observed following the HIFT (p < 0.001; pre: 56.0 ± 16.8, post: 61.6 ± 19.0 [Newton]) and no change following the control (p = 0.067; pre: 56.6 ± 18.4, post: 55.3 ± 18.9 [Newton]). Further, a significant 'Time' × 'Intervention' × 'Landmark' interaction effect (p = 0.024) is observed and all landmarks showed significant hypoalgesia following HIFT (p < 0.01), except for the right elbow and forehead. Following control, no hypoalgesia was observed at any landmark. Analysing male and female participants separately, it was observed that EIH occured only in men. Conclusion: A HIFT using bodyweight exercises reduces pain sensitivity. Hence, combining strength and aerobically demanding exercises in a short but high intensity manner, as done in HIFT, can be seen as a usable tool to induce hypoalgesia. Yet, these results were observed only in male participants, necessitating future sex-specific research. Trial registration: DRKS00034391, retrospectively registered on the 4th of June 2024. [ABSTRACT FROM AUTHOR]

Major depressive disorder (MDD) is currently the most common psychiatric disorder in the world. It characterized by a high incidence of disease with the symptoms like depressed mood, slowed thinking, and reduced cognitive function. Without timely intervention, there is a 20–30% risk of conversion to treatment-resistant depression (TRD) and a high burden for the patient, family and society. Numerous studies have shown that physical activity (PA) is a nonpharmacological treatment that can significantly improve the mental status of patients with MDD and has positive effects on cognitive function, sleep status, and brain plasticity. However, the physiological and psychological effects of different types of PA on individuals vary, and the dosage profile of PA in improving symptoms in patients with MDD has not been elucidated. In most current studies of MDD, PA can be categorized as continuous endurance training (ECT), explosive interval training (EIT), resistance strength training (RST), and mind–body training (MBT), and the effects on patients’ depressive symptoms, cognitive function, and sleep varied. Therefore, the present study was based on a narrative review and included a large number of existing studies to investigate the characteristics and differences in the effects of different PA interventions on MDD. The study also investigated the characteristics and differences of different PA interventions in MDD, and explained the neural mechanisms through the results of multimodal brain function monitoring, including the intracranial environment and brain structure. It aims to provide exercise prescription and theoretical reference for future research in neuroscience and clinical intervention in MDD. [ABSTRACT FROM AUTHOR]

Purpose: Blood-flow restriction (BFR) endurance training may increase endurance performance and muscle strength similar to traditional endurance training while requiring a lower training intensity. We aimed to compare acute cardiorespiratory responses to low-intensity interval exercise under BFR with moderate-intensity traditional interval exercise (TRA). Methods: We conducted a randomized crossover study. The protocol involved three cycling intervals interspersed with 1 min resting periods. With a 48-h washout period, individuals performed the protocol twice in random order: once as BFR-50 (i.e., 50% incremental peak power output [IPPO] and 50% limb occlusion pressure [LOP]) and once as TRA-65 (65% IPPO without occlusion). TRA-65 intervals lasted 2 min, and time-matched BFR-50 lasted 2 min and 18 s. Respiratory parameters were collected by breath-by-breath analysis. The ratings of perceived breathing and leg exertion (RPE, 0 to 10) were assessed. Linear mixed models were used for analysis. Results: Out of the 28 participants initially enrolled in the study, 24 healthy individuals (18 males and 6 females) completed both measurements. Compared with TRA-65, BFR-50 elicited lower minute ventilation (VE, primary outcome) (-3.1 l/min [-4.4 to -1.7]), oxygen consumption (-0.22 l/min [-0.28 to -0.16]), carbon dioxide production (-0.25 l/min [-0.29 to -0.20]) and RPE breathing (-0.9 [-1.2 to -0.6]). RPE leg was significantly greater in the BFR-50 group (1.3 [1.0 to 1.7]). Conclusion: BFR endurance exercise at 50% IPPO and 50% LOP resulted in lower cardiorespiratory work and perceived breathing effort compared to TRA at 65% IPPO. BFR-50 could be an attractive alternative for TRA-65, eliciting less respiratory work and perceived breathing effort while augmenting perceived leg muscle effort. Trial registration: NCT05163600; December 20, 2021. [ABSTRACT FROM AUTHOR]

Background and purpose: Time-restricted feeding (TRF) is a dietary pattern that alternates between periods of fasting and feeding, which has gained significant attention in recent years. The 16/8 approach consists of fasting for 16 h and feeding for an 8-h window, while the 12/12 method consists of fasting for 12 h and a 12-h feeding window. Limited research exists comparing the effects of these methods coupled with physical activity (PA). The aim of this investigation was to examine the acute effects between conditions of varying TRF durations (12 and 16 h) and PA intensities on the fat oxidation rate (FOR). It was hypothesized that i) the TRF16 conditions would exhibit higher FORmax and that PA would enhance these effects, and ii) High Intensity Interval Training (HIIT) would result in greater effects on FORmax compared to Low-Moderate Intensity Steady State Continuous Training (MICT) PA. Methods and results: Eighteen young adults (age: 23 ± 2.0 yrs., body mass index: 23.5 ± 2.8 kg·m−2) were recruited and participated in the supervised intervention. The discrete component open circuit spirometry system was used to measure oxygen consumption (VO2), and Frayne's equation was used to determine the FOR plus FORmax. ANOVA was used to determine pre/post-intervention differences in FORmax. The FORmax for the TRF16 + HIIT intervention was significantly higher than the TRF12 (mean difference = 0.099 g·min-1, p = 0.011, 95% CI 0.017 to 0.180) and TRF16 fast alone (mean difference = 0.093 g·min-1, p = 0.002, 95% CI 0.027 to 0.159). The FORmax for TRF12 + HIIT intervention was significantly higher than the TRF12 fast alone (mean difference = 0.070 g·min−1, p = 0.023, 95% CI 0.007 to 0.134). The TRF16 + HIIT intervention was also significantly higher than the TRF12 fast alone (mean difference = 0.099 g·min−1, p = 0.011, 95% CI 0.017 to 0.180). Conclusion: This study contributes to the ever-growing body of literature on the acute effects of TRF and PA on young adult males and females. The findings suggest that the TRF16 + HIIT PA intervention results in the highest FORmax. Trial registration: Retrospective Registration ISRCTN # 10076373 (October 6, 2023). [ABSTRACT FROM AUTHOR]

Summary Sleep disturbances are common in individuals with posttraumatic stress disorder. Exercise interventions are a promising approach in the treatment of sleep disorders, but little is known about the efficacy of exercise interventions for sleep disturbances associated with posttraumatic stress disorder. A total of 40 individuals with posttraumatic stress disorder were randomized to six sessions of either high‐intensity interval training or low‐to‐moderate‐intensity training, administered within 12 days. Sleep quality was assessed over 24 days from baseline to post with the Pittsburgh Sleep Quality Index, a sleep log, and a waist‐worn actigraphy. Analyses revealed that, regardless of group allocation, Pittsburgh Sleep Quality Index score improved significantly by 2.28 points for high‐intensity interval training and 1.70 points for low‐to‐moderate‐intensity training (d = 0.56 for high‐intensity interval training; 0.49 for low‐to‐moderate‐intensity training) over time, while there were no significant changes in any sleep log or actigraphy measure. Analysis of a subsample of those affected by clinically significant sleep disturbances (n = 24) revealed a significant time effect with no difference between exercise interventions: Pittsburgh Sleep Quality Index improved significantly by 2.65 points for high‐intensity interval training and 2.89 points for low‐to‐moderate‐intensity training (d = 0.53 for high‐intensity interval training; 0.88 for low‐to‐moderate‐intensity training), and actigraphy measure of wake after sleep onset was reduced significantly by 14.39 minutes for high‐intensity interval training and 6.96 minutes for low‐to‐moderate‐intensity training (d = 0.47 for high‐intensity interval training; 0.11 for low‐to‐moderate‐intensity training) from baseline to post. In our pilot study, we found an improvement in sleep quality from pre‐ to post‐assessment. There were no significant differences between exercise groups. Further studies are needed to investigate whether the found time effects reflect the exercise intervention or unrelated factors. [ABSTRACT FROM AUTHOR]

We investigated the influence of short‐ and long‐interval cycling exercise with blood flow restriction (BFR) on neuromuscular fatigue, shear stress and muscle oxygenation, potent stimuli to BFR‐training adaptations. During separate sessions, eight individuals performed short‐ (24 × 60 s/30 s; SI) or long‐interval (12 × 120 s/60 s; LI) trials on a cycle ergometer, matched for total work. One leg exercised with (BFR‐leg) and the other without (CTRL‐leg) BFR. Quadriceps fatigue was quantified using pre‐ to post‐interval changes in maximal voluntary contraction (MVC), potentiated twitch force (QT) and voluntary activation (VA). Shear rate was measured by Doppler ultrasound at cuff release post‐intervals. Vastus lateralis tissue oxygenation was measured by near‐infrared spectroscopy during exercise. Following the initial interval, significant (P < 0.05) declines in MVC and QT were found in both SI and LI, which were more pronounced in the BFR‐leg, and accounted for approximately two‐thirds of the total reduction at exercise termination. In the BFR‐leg, reductions in MVC (–28 ± 15%), QT (–42 ± 17%), and VA (–15 ± 17%) were maximal at exercise termination and persisted up to 8 min post‐exercise. Exercise‐induced muscle deoxygenation was greater (P < 0.001) in the BFR‐leg than CTRL‐leg and perceived pain was more in LI than SI (P < 0.014). Cuff release triggered a significant (P < 0.001) shear rate increase which was consistent across trials. Exercise‐induced neuromuscular fatigue in the BFR‐leg exceeded that in the CTRL‐leg and was predominantly of peripheral origin. BFR also resulted in diminished muscle oxygenation and elevated shear stress. Finally, short‐interval trials resulted in comparable neuromuscular and haemodynamic responses with reduced perceived pain compared to long‐intervals. What is the central question of this study?Does modifying exercise–rest durations during low‐intensity blood‐flow‐restricted (BFR) interval aerobic exercise modulate neuromuscular fatigue development, shear stress and muscle oxygenation?What is the main finding and its importance?BFR interval exercise resulted in significantly greater neuromuscular fatigue, predominantly of peripheral origin, compared to exercise with unrestricted blood flow. Furthermore, shorter BFR intervals elicited comparable neuromuscular and haemodynamic responses compared to longer intervals. These findings have important implications for developing optimized BFR training interventions and for future studies assessing whether these acute stimuli translate into enhanced physiological adaptations and subsequent improvements in performance. [ABSTRACT FROM AUTHOR]

The aim of this work is to determine the effect of upper‐body high intensity interval training (HIIT) on cardiometabolic risks in individuals with chronic paraplegia. Twenty‐seven individuals (14 females, 13 males, mean ± SD age: 46 ± 9 years) with chronic paraplegia (spinal cord injury between T2 and L5 >1‐year post‐injury) took part in a randomized controlled trial and were included in the final analysis. Participants in the HIIT group (n = 18) performed ∼30 min of arm crank exercise (60 s intervals at 80%–90% peak heart rate) four times per week, for 6 weeks. Participants in the control (CON) group (n = 9) were asked to maintain their habitual diet and physical activity patterns over the study period. Outcome measures were taken at baseline and follow‐up. The primary outcome measures were fasting insulin, peak power output (PPO) and peak aerobic capacity (V̇O2peak${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{peak}}}}$). Secondary outcome measures included body composition, postprandial glycaemic control, fasting blood lipids, inflammatory biomarkers and resting blood pressure. Differences between groups were assessed by ANCOVA, using baseline values as a covariate. PPO was higher in the HIIT (101 W, 97–106) compared to the CON (90 W, 83–96) group at follow‐up (P = 0.006). There were no differences in fasting insulin (P = 0.415) or relative V̇O2peak${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{peak}}}}$ (P = 0.417). Postprandial Matsuda insulin sensitivity index (ISIMatsuda) was higher in the HIIT (5.42, 4.69–6.15) compared to the CON (3.75, 2.46–5.04) group at follow‐up (P = 0.036). Six weeks of upper‐body HIIT increased PPO and ISIMatsuda, with no other beneficial effect on cardiometabolic component risks in persons with chronic paraplegia. Highlights: What is the central question of this study?What is the effect of upper‐body high intensity interval training (HIIT) on cardiometabolic component risks in individuals with chronic paraplegia?What is the main finding and its importance?Six weeks of upper‐body HIIT increased PPO and improved insulin sensitivity, but had no beneficial effect on other cardiometabolic component risks in persons with chronic paraplegia. The large effect size observed for insulin sensitivity may be important in terms of reducing the risk of type‐2 diabetes in this population. [ABSTRACT FROM AUTHOR]

Summary: Acute exercise has been shown to affect long‐term memory and sleep. However, it is unclear whether exercise‐induced changes in sleep architecture are associated with enhanced memory. Recently, it has been shown that exercise followed by a nap improved declarative memory. Whether these effects transfer to night sleep and other memory domains has not yet been studied. Here, we investigate the influence of exercise on nocturnal sleep architecture and associations with sleep‐dependent procedural and declarative memory consolidation. Nineteen subjects (23.68 ± 3.97 years) were tested in a balanced cross‐over design. In two evening sessions, participants either exercised (high‐intensity interval training) or rested immediately after encoding two memory tasks: (1) a finger tapping task and (2) a paired‐associate learning task. Subsequent nocturnal sleep was recorded by polysomnography. Retrieval was conducted the following morning. High‐intensity interval training lead to an increased declarative memory retention (p = 0.047, d = 0.40) along with a decrease in REM sleep (p = 0.012, d = 0.75). Neither procedural memory nor NREM sleep were significantly affected. Exercise‐induced changes in N2 showed a positive correlation with procedural memory retention which did not withstand multiple comparison correction. Exploratory analyses on sleep spindles and slow wave activity did not reveal significant effects. The present findings suggest an exercise‐induced enhancement of declarative memory which aligns with changes in nocturnal sleep architecture. This gives additional support for the idea of a potential link between exercise‐induced sleep modifications and memory formation which requires further investigation in larger scaled studies. [ABSTRACT FROM AUTHOR]

A computer-based age estimation is a technique that predicts an individual's age based on visual traits derived by analyzing a 2D picture of the individual's face. Age estimation is critical for access control, e-government, and effective human–computer interaction. The other-race effect has the potential to cause techniques designed for white faces to underperform when used in a region with black faces. The outcome is the consequence of intermittent training with faces of the same race and the encoding structure of the trained face images, which is based on the feature extraction technique used. This study contributes to a constructive comparison of three feature-extraction techniques, namely, local binary pattern (LBP), Gabor Wavelet (GW), and wavelet transformation, used in the development of a genetic algorithm (GA)-artificial neural network (ANN)-based age estimation system. The feature extraction techniques used are proven to produce a wealth of shape and textural information. The GA-ANN constitutes the age classifier module. The correct classification rate was chosen as the performance metrics in this study. The results demonstrated that the LBP is a more robust representation of the black face than the GW and Wavelet transformations, as evidenced by its accuracy rate of 91.76 compared to 89.41 and 84.71 achieved with the GW and Wavelet transformation age estimation systems, respectively. [ABSTRACT FROM AUTHOR]

Introduction: Dichoptic training has emerged as a promising rehabilitation approach for improving binocular visual function in patients with strabismus. A prospective observational study design was employed to assess the effectiveness of online video game-based dichoptic training in rehabilitating binocular visual function in patients who had undergone an operation for intermittent exotropia. Methods: A total of 64 patients who had undergone an operation for intermittent exotropia were recruited and divided into the training group and the control group based on whether they would receive the dichoptic training. The dichoptic training was conducted for 3 months in the training group and the control group would not accept any form of orthoptic therapy. Assessments of binocular visual functions and deviation were conducted at baseline, 3-month and 6-month follow-up. Results: Twenty-nine participants in the training group (mean 9.69 ± 2.66 years old) and 26 participants in the control group (mean 8.41 ± 2.64 years old) completed follow-up. At both 3- and 6-month follow-ups, the training group showed superior distance stereopsis compared to the control group, with near stereopsis only showing significant difference at the 6-month follow-up. Additionally, the training group exhibited significantly less distance exo-deviation drift than the control group at these times, and no significant difference was observed in near exo-deviation drift between the groups. The control group had a significantly higher rate of suboptimal surgical outcomes at both the 3- and 6-month follow-up. However, no significant differences were observed in simultaneous perception and fusion functions between the two groups. Conclusions: Online video game-based dichoptic training has the potential to become a novel postoperative rehabilitation strategy for patients with intermittent exotropia. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of 8-week aquatic and land high intensity interval training (HIIT) on hemodynamics and vascular function in middle-aged men. Methods: Thirty middle-aged men with low physical activity were selected and divided into 15 men (52.43 ± 4.11) in aquatic group and 15 men (52.74 ± 5.62) in land group by random number table. They performed HIIT exercise in aquatic and land 3 times a week for 8 weeks. Pre-test, inter-test and post-test respectively measure hemodynamics and blood vessel function. Results: (1) Body composition: After 8 weeks of exercise, weight, body mass index (BMI) and body fat rate (BF) were lower than before exercise (aquatic group: p < 0.01, land group: p < 0.05). The improvement of BF in the aquatic group was better than that in the land group (p < 0.05); (2) Cardiac function: After 8 weeks of exercise, stroke volume (SV), left ventricular end-diastolic volume (EDV), cardiac output (CO), and left ventricular fractional shortening (FS), were higher than before exercise (aquatic group: p < 0.01, land group: p < 0.05), heart rate (HR) and left ventricular endsystolic volume (ESV) were lower than before exercise (aquatic group: p < 0.01, land group: p < 0.05). The improvement of SV, HR, EDV, ESV, CO and FS in the aquatic group was better than that in the land group (p < 0.05); (3) Hemodynamics: After 8 weeks of exercise, systolic blood pressure (SBP), diastolic blood pressure (DBP) were lower than before exercise (aquatic group: p < 0.01, land group: p < 0.05), wall shear stress (WSS) and peak systolic velocity (PSV) were higher than before exercise (aquatic group: p < 0.01, land group: p < 0.05). The improvement of SBP, WSS and PSV in the aquatic group was better than that in the land group (p < 0.05); (4) Vascular function: basal diameter and brachial artery flow-mediated dilatation (FMD) level in aquatic group and land group was higher than before exercise, pulse wave velocity (PWV) level was lower than before exercise (aquatic and land group: p < 0.05). The improvement of FMD in the aquatic group was better than that in the land group. Conclusion: The body composition, hemodynamics and vascular function of middle-aged men were improved by 8-week aquatic and land HIIT. Aquatic HIIT has better effect on body fat rate, hemodynamics and vascular endothelial function in middle-aged men due to the effect of aquatic pressure and temperature. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusions Consequences of spinal cord injury (SCI) with a sedentary lifestyle will progress to muscle weakness and muscle atrophy, leading to muscle fatigue. This study aimed to determine the feasibility and preliminary effects of high‐intensity interval training (HIIT) using functional electrical stimulation (FES) cycling on changes in thigh muscle volume and muscle strength, in patients with incomplete SCI.Eight incomplete SCI patients (mean age 50 years; 6 women) with stable SCI paraplegia (mean 6.75 years since injury) participated in the HIIT FES cycling (85%–90% peak Watts; 4 × 4–min intervals) three times a week (over 6 weeks). The main outcomes were adherence, participant acceptability, and adverse events. Secondary outcomes were muscle strength (peak torque) and leg volume changes.Our findings revealed that the program was well‐received by participants, with high levels of adherence, positive feedback, and satisfaction, suggesting that it could be a promising option for individuals seeking to enhance their lower body strength and muscle mass. Additionally, all participants successfully completed the training without any serious adverse events, indicating that the program is safe for use. Finally, we found that the 6‐week HIIT FES leg cycling exercise program resulted in notable improvements in isometric peak torque of the quadriceps (range 13.9%–25.6%), hamstring muscle (18.2%–23.3%), and leg volume (1.7%–18.2%).This study highlights HIIT FES leg cycling exercise program potential as an effective intervention for improving lower limb muscle function. [ABSTRACT FROM AUTHOR]

This study aimed to elucidate the impact of combining Beta-Alanine (BA) supplementation with short sprint interval training on cardiorespiratory fitness, anaerobic power, and bio-motor abilities in volleyball players. Twenty young male athletes were randomly divided into 2 equal groups and performed 8 weeks of short sprint interval training while supplementing 4.8 g daily BA or placebo (polydextrose). The players were evaluated for volleyball-specific bio-motor abilities (vertical jump, horizontal jump, spike jump, block jump, 10-m linear sprint, and T-test change of direction speed) and physiological parameters (cardiorespiratory fitness and anaerobic power) pre- and post-intervention. Both groups demonstrated significant (p ≤ 0.05) improvements in all measured variables over time. A time-regimen interaction was observed in jumping ability enhancement from pre- to post-training, wherein BA elicited more significant changes in both vertical and horizontal jumps compared to the placebo. Analyzing residuals in changes and the coefficient of variations (CV) in mean group changes demonstrated that BA supplementation results in uniformly inducing adaptive changes among individuals. Therefore, in light of these results, it is recommended that coaches and trainers take into consideration the utilization of BA as an ergogenic aid to enhance the vertical and horizontal jumps of volleyball players and increase the homogeneity in adaptive responses over the training period. [ABSTRACT FROM AUTHOR]

• Cortical excitability does not change following acute HIIT. • Acute HIIT enhances working memory and mental rotation in healthy young adults. • Acute HIIT boosts serum BDNF and CTSB levels, implying potential neuroprotection. High-intensity interval training (HIIT) is a time-efficient, safe, and feasible exercise type that can be utilized across different ages and health status. This randomized cross-over study aimed to investigate the effect of acute HIIT on cortical excitability, M1-related cognitive functions, cognition-related myokines, brain-derived neurotrophic factor (BDNF), and Cathepsin B (CTSB). Twenty-three sedentary young adults (mean age: 22.78 years ± 2.87; 14 female) participated in a cross-over design involving two sessions: either 23 min of HIIT or seated rest. Before and after the sessions, cortical excitability was measured using transcranial magnetic stimulation, and M1-related cognitive functions were assessed by the n-back test and mental rotation test. Serum levels of BDNF and CTSB were assessed using the ELISA method before and after the HIIT intervention. We demonstrated that HIIT improved mental rotation and working memory, and increased serum levels of BDNF and CTSB, whereas cortical excitability did not change. Our findings provide evidence that one session of HIIT is effective on M1-related cognitive functions and cognition-related myokines. Future research is warranted to determine whether such findings are transferable to different populations, such as cognitively at-risk children, adults, and older adults, and to prescribe effective exercise programs. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare different high-intensity interval training (HIIT) protocols with different lengths of work and rest times for a single session (all three had identical work-to-rest ratios and exercise intensities) for cardiac auto-regulation using a wearable device. With a randomized counter-balanced crossover, 13 physically active young male adults (age: 19.4 years, BMI: 21.9 kg/m2) were included. The HIIT included a warm-up of at least 5 min and three protocols of 10 s/50 s (20 sets), 20 s/100 s (10 sets), and 40 s/200 s (5 sets), with intensities ranging from 115 to 130% Wattmax. Cardiac auto-regulation was measured using a non-invasive method and a wearable device, including HRV and vascular function. Immediately after the HIIT session, the 40 s/200 s protocol produced the most intense stimulation in R-R interval (Δ-33.5%), ln low-frequency domain (Δ-42.6%), ln high-frequency domain (Δ-73.4%), and ln LF/HF ratio (Δ416.7%, all p < 0.05) compared to other protocols of 10 s/50 s and 20 s/100 s. The post-exercise hypotension in the bilateral ankle area was observed in the 40 s/200 s protocol only at 5 min after HIIT (right: Δ-12.2%, left: Δ-12.6%, all p < 0.05). This study confirmed that a longer work time might be more effective in stimulating cardiac auto-regulation using a wearable device, despite identical work-to-rest ratios and exercise intensity. Additional studies with 24 h measurements of cardiac autoregulation using wearable devices in response to various HIIT protocols are warranted. [ABSTRACT FROM AUTHOR]

While it is well‐established that a period of interval training performed at near maximal effort, such as speed endurance training (SET), enhances intense exercise performance in well‐trained individuals, less is known about its effect on cardiac morphology and function as well as blood volume. To investigate this, we subjected 12 Under‐20 Danish national team ice hockey players (age 18 ± 1 years, mean ± SD) to 4 weeks of SET, consisting of 6–10 × 20 s skating bouts at maximal effort interspersed by 2 min of recovery conducted three times weekly. This was followed by 4 weeks of regular training (follow‐up). We assessed resting cardiac function and dimensions using transthoracic echocardiography and quantified total blood volume with the carbon monoxide rebreathing technique at three time points: before SET, after SET and after the follow‐up period. After SET, stroke volume had increased by 10 (2–18) mL (mean (95% CI)), left atrial end‐diastolic volume by 10 (3–17) mL, and circumferential strain improved by 0.9%‐points (1.7–0.1) (all P < 0.05). At follow‐up, circumferential strain and left atrial end‐diastolic volume were reverted to baseline levels, while stroke volume remained elevated. Blood volume and morphological parameters for the left ventricle, including mass and end‐diastolic volume, did not change during the study. In conclusion, our findings demonstrate that a brief period of SET elicits beneficial central cardiac adaptations in elite ice hockey players independent of changes in blood volume. [ABSTRACT FROM AUTHOR]

Previous studies have explored the effect of differing heat and relative humidity (RH) environments on the performance of multiple anaerobic high-intensity interval training (HIIT). Still, its impact on physiological responses and performance following aerobic HIIT has not been well studied. This study examined the effects of differing RH environments on physiological responses and performance in college football players following HIIT. Twelve college football completed HIIT under four different environmental conditions: (1) 25 °C/20% RH (Control group); (2) 35 °C/20% RH (H20 group); (3) 35 °C/40% RH (H40 group); (4) 35 °C/80% RH (H80 group). The heart rate (HR), mean arterial pressure (MAP), lactate, tympanic temperature (TT), skin temperature (TS), thermal sensation (TS), and rating of perceived exertion (RPE) were recorded continuously throughout the exercise. The heart rate variability (HRV): including root mean squared differences of the standard deviation (RMSSD)、standard deviation differences of the standard deviation (SDNN)、high frequency (HF), low frequency (LF), squat jump height (SJH), cycling time to exhaustion (TTE), and sweat rate (SR) were monitored pre-exercise and post-exercise. The HR, MAP, lactate, TT, Ts, TS, and RPE in the 4 groups showed a trend of rapid increase, then decreased gradually. There was no significant difference in HR, MAP, TT, or RPE between the 4 groups at the same time point (p > 0.05), in addition to this, when compared to the C group, the lactate, Ts, TS in the other 3 groups significant differences were observed at the corresponding time points (p < 0.05). The RMSSD, SDNN, HF, and LF levels in the 4 groups before exercise were not significantly different. The RMSSD and HF in the H40 and H80 groups were significantly decreased and other HRV indicators showed no significant difference after exercise. In sports performance measurement, the SJH and TTE were significantly decreased, but there was no significant difference in the 4 groups. The SR was no significant difference in the 4 groups after exercise. In conclusion, heat and humidity environments elicited generally greater physiological effects compared with the normal environment but did not affect sports performance in college football players. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is a demyelinating and neurodegenerative disease due to an autoimmune chronic inflammatory response, yet the etiology is currently not completely understood. It is already known that physical activity plays an essential role in improving quality of life, especially in neuropathological conditions. The study was aimed to investigate the possible benefits of high-intensity interval training (HIIT) in bone and lipid metabolism markers, and neuromotor abilities in MS patients. 130 participants were recruited; 16 subjects with MS met the inclusion criteria and were included in the data analysis. The patients were randomly assigned to two groups: a Control group (CG) (34.88 ± 4.45 yrs) that didn't perform any physical activity and the Exercise group (EG) (36.20 ± 7.80 yrs) that performed HIIT protocol. The training program was conducted remotely by a kinesiologist. It was performed three times a week for 8 weeks. At the beginning (T0) and the end of the study (T1) physical function tests, bone remodelling markers, and lipid markers analyses were performed. After 8 weeks of training the wall squat (s) (T0 = 27.18 ± 4.21; T1 = 41.68 ± 5.38, p ≤ 0.01) and Time Up and Go test (s) (T0 = 7.65 ± 0.43; T1 = 6.34 ± 0.38 p ≤ 0.01) performances improved; lipid markers analysis showed a decrease in Total (mg/dl) (T0 = 187.22 ± 15.73; T1 = 173.44 ± 13.03, p ≤ 0.05) and LDL (mg/dl) (T0 = 108 ± 21.08; T1 = 95.02 ± 17.99, p < 0.05) cholesterol levels. Additionally, the levels of osteocalcin (µg/L), a marker of bone formation increased (T0 = 20.88 ± 4.22; T1 = 23.66 ± 6.24, p < 0.05), 25-OH Vitamin D (µg/L) improved after 8 weeks (T0 = 21.11 ± 7.11; T1 = 27.66 ± 7.59, p < 0.05). HIIT had an effect on lower limb strength and gait control, improved bone formation, and lipid management, in MS patients. [ABSTRACT FROM AUTHOR]

Background: The increasing popularity of hypoxic training as a training method to improve physical performance indicates the need to study the effects of this type of intervention on blood morphological and rheological indices, since the adaptive changes that follow such training mainly affect blood indices. In this study, the effects of a 4 weeks of intermittent hypoxic training on blood morphological and rheological indicators in physically active men were assessed. Methods: Forty-eight young, physically active men, participated in the study. Participants were randomly divided into three groups: two training groups and a control group without intervention (CTRL). Each group consisted of 16 participants. Training groups performed interval training (three times per week, 4 weeks, 12 workouts) under different conditions: in hypoxia (IHT; fraction of inspired oxygen (FiO2) = 14.4%) or in normoxia (NT; FiO2 = 20.9%). The control group performed only two workouts 4 weeks apart. Blood was taken during the first and last training session at rest, and 3 minutes after training. Results: After the last training session, there was a significant increase in mean corpuscular volume and a decrease in mean corpuscular haemoglobin concentration measured at rest only in the IHT group. There was also a significant decrease in resting aggregation amplitude for the IHT and CTRL groups. There was no difference in change of post-exercise plasma volume between first and last training session. Conclusion: The applied intermittent interval training in conditions of normoxia and hypoxia had no significant impact on resting aggregation parameters. This suggest that training under hypoxic conditions does not cause adverse rheological changes. [ABSTRACT FROM AUTHOR]

The protocol predefined aim of this study is to assess sustained effects of the OptiTrain trial on several health outcomes, 5 years after the baseline assessment. The OptiTrain study was a prospective, randomised controlled trial with 240 patients with breast cancer undergoing adjuvant chemotherapy that compared the effects of 16 weeks of two exercise programs, RT-HIIT and AT-HIIT, with usual care (UC). After a 5-year follow-up, eligible participants were evaluated for the primary outcome of cancer-related fatigue (CRF) and secondary outcomes including quality of life, symptoms, muscle strength, cardiorespiratory fitness, body mass, physical activity, and sedentary behavior. Statistical analysis was conducted using linear mixed models adjusted for baseline values. Tumour profile and menopausal status were additionally adjusted for CRF. Mean differences (MD), 95% confidence intervals (CIs), and standardized effect sizes (ES) were reported. At the 5-year follow-up, there were no statistically significant differences in total CRF between the intervention groups and the UC group. RT-HIIT reported significantly reduced pain sensitivity at the gluteus MD = 79.00 (95% CI 10.17, 147.83, ES = 0.55) compared to UC. Clinically meaningful differences for an increase in cognitive CRF and cardiorespiratory fitness were observed for the AT-HIIT versus UC group, and for lower limb strength for the RT-HIIT versus UC group, albeit without statistical significance. Engaging in targeted exercise during adjuvant chemotherapy for breast cancer provides short-term benefits in reducing fatigue and maintaining physical function. However, our 5-year follow-up indicates that these effects are limited in the long term. This underscores the need to support breast cancer survivors maintain their PA levels throughout their survivorship journey. [ABSTRACT FROM AUTHOR]

Although the effects of exercise training (ET) on sleep problem have been reported, the effects according to the components of exercise, including intensity, frequency, and time window, are unknown. Thus, in this study, we aimed to assess the effects of ET on sleep quality in community-dwelling older adults with sleep problems. We evaluated individuals aged ≥65 years whose Pittsburgh sleep quality index was >5 points at baseline. The participants were allocated to either the control group or the ET group and underwent interval walking training (IWT) for 5 months. Information regarding intensity, frequency, and time window of ET were obtained using a waist-worn accelerometer. Overall, 63 participants (24 men [mean ± standard deviation age: 75.1 ± 4.6 years] and 39 women [74.7 ± 5.2 years]) and 65 participants (24 men [75.2 ± 4.0 years] and 41 women [73.6 ± 4.2 years]) were included in the ET and control groups, respectively. The change in Pittsburgh sleep quality index was not significantly different between the two groups for both sexes. In the ET group, women who exercised 3–8 h before bedtime, men who did ET > 8 h before bedtime and more than 1 h after waking up, and men who did ET ≥ 5.05 days/week experienced significant improvements compared to the baseline. IWT does not significantly improve sleep quality. To obtain improvements in sleep quality, it might be necessary to consider the time window of performing ET for both sexes and ET frequency for men. • Exercise training has no significant effect on sleep quality. • Sleep quality improves the most among women who exercise 3–8 h before bedtime. • Exercise effects are not significantly different by intensity or frequency. [ABSTRACT FROM AUTHOR]

Introduction: Concurrent training has been shown to be a beneficial approach to improve overall health status in older adults. However, little is known about the adaptations of this type of training in the long term (i.e., after cessation of exercise), even less in older people affected by frailty syndrome. Therefore, this study aimed (i) to assess the effects of a 6-week concurrent training program composed of power-oriented resistance training and fast walking interval training on physical function, muscle power, disability in activities of daily living and frailty in pre-frail and frail older people, and (ii) to assess the effects of a 6-month detraining period on these outcomes. Methods: A total of 59 pre-frail and frail older adults (>75 years old; Frailty Phenotype >1) were allocated into intervention (INT; n = 32; 81.8 years; 21 women) or control (CON; n = 27; 82.5 years; 19 women) groups. Primary outcomes of this study were Short Physical Performance Battery (SPPB), relative sit-to-stand (STS) power, Barthel index, Lawton scale and Frailty Phenotype. Assessments were performed at baseline (PRE), after the concurrent training programme (POST) and after 6 months of follow-up (DET) in both groups. Mixed model repeated measures ANOVA with Bonferroni's post hoc tests was used. Results: Immediately after the intervention (∆ = POST-PRE), INT improved SPPB (∆ = 3.0 points; p < 0.001), relative STS power (∆ = 0.87 W·kg−1; p < 0.001) and reduced their frailty levels (∆ = −1.42 criteria; p < 0.001), while no changes were observed in CON. After 6 months of detraining (∆ = DET-PRE), INT showed higher SPPB (∆ = 2.2 points; p < 0.001), higher relative STS power (∆ = 0.73 W·kg−1; p < 0.001) and lower frailty (∆ = −1.24 criteria; p < 0.001) values than those reported at baseline, which were significantly different than those reported by CON. Both, Barthel index and Lawton scale values were not modified during the study in either group. Conclusions: The 6-week concurrent training program improved physical function, muscle power and reduced frailty in pre-frail and frail older people and these improvements were maintained above baseline levels after 6 months of detraining. However, due to the individual variability found, future studies of long-term responders versus non-responders in frail populations are required. [ABSTRACT FROM AUTHOR]

Abstract Purpose Blood-flow restriction (BFR) endurance training may increase endurance performance and muscle strength similar to traditional endurance training while requiring a lower training intensity. We aimed to compare acute cardiorespiratory responses to low-intensity interval exercise under BFR with moderate-intensity traditional interval exercise (TRA). Methods We conducted a randomized crossover study. The protocol involved three cycling intervals interspersed with 1 min resting periods. With a 48-h washout period, individuals performed the protocol twice in random order: once as BFR-50 (i.e., 50% incremental peak power output [IPPO] and 50% limb occlusion pressure [LOP]) and once as TRA-65 (65% IPPO without occlusion). TRA-65 intervals lasted 2 min, and time-matched BFR-50 lasted 2 min and 18 s. Respiratory parameters were collected by breath-by-breath analysis. The ratings of perceived breathing and leg exertion (RPE, 0 to 10) were assessed. Linear mixed models were used for analysis. Results Out of the 28 participants initially enrolled in the study, 24 healthy individuals (18 males and 6 females) completed both measurements. Compared with TRA-65, BFR-50 elicited lower minute ventilation (VE, primary outcome) (-3.1 l/min [-4.4 to -1.7]), oxygen consumption (-0.22 l/min [-0.28 to -0.16]), carbon dioxide production (-0.25 l/min [-0.29 to -0.20]) and RPE breathing (-0.9 [-1.2 to -0.6]). RPE leg was significantly greater in the BFR-50 group (1.3 [1.0 to 1.7]). Conclusion BFR endurance exercise at 50% IPPO and 50% LOP resulted in lower cardiorespiratory work and perceived breathing effort compared to TRA at 65% IPPO. BFR-50 could be an attractive alternative for TRA-65, eliciting less respiratory work and perceived breathing effort while augmenting perceived leg muscle effort. Trial registration NCT05163600; December 20, 2021.

Abstract We investigated the influence of short‐ and long‐interval cycling exercise with blood flow restriction (BFR) on neuromuscular fatigue, shear stress and muscle oxygenation, potent stimuli to BFR‐training adaptations. During separate sessions, eight individuals performed short‐ (24 × 60 s/30 s; SI) or long‐interval (12 × 120 s/60 s; LI) trials on a cycle ergometer, matched for total work. One leg exercised with (BFR‐leg) and the other without (CTRL‐leg) BFR. Quadriceps fatigue was quantified using pre‐ to post‐interval changes in maximal voluntary contraction (MVC), potentiated twitch force (QT) and voluntary activation (VA). Shear rate was measured by Doppler ultrasound at cuff release post‐intervals. Vastus lateralis tissue oxygenation was measured by near‐infrared spectroscopy during exercise. Following the initial interval, significant (P

Abstract This study aimed to elucidate the impact of combining Beta-Alanine (BA) supplementation with short sprint interval training on cardiorespiratory fitness, anaerobic power, and bio-motor abilities in volleyball players. Twenty young male athletes were randomly divided into 2 equal groups and performed 8 weeks of short sprint interval training while supplementing 4.8 g daily BA or placebo (polydextrose). The players were evaluated for volleyball-specific bio-motor abilities (vertical jump, horizontal jump, spike jump, block jump, 10-m linear sprint, and T-test change of direction speed) and physiological parameters (cardiorespiratory fitness and anaerobic power) pre- and post-intervention. Both groups demonstrated significant (p ≤ 0.05) improvements in all measured variables over time. A time-regimen interaction was observed in jumping ability enhancement from pre- to post-training, wherein BA elicited more significant changes in both vertical and horizontal jumps compared to the placebo. Analyzing residuals in changes and the coefficient of variations (CV) in mean group changes demonstrated that BA supplementation results in uniformly inducing adaptive changes among individuals. Therefore, in light of these results, it is recommended that coaches and trainers take into consideration the utilization of BA as an ergogenic aid to enhance the vertical and horizontal jumps of volleyball players and increase the homogeneity in adaptive responses over the training period.

The present article aimed to systematically summarize primary school-based intervention programs and their effects evaluated through randomized-controlled trial design. A systematic review of relevant articles was carried out using 4 electronic databases. From a total of 193 studies initially found, 30 were included in the qualitative synthesis. Main results: (1) Intensive interval training or jump/strength exercises may positively influence physical fitness, promoting challenging task, psychological needs, and guided styles to a greater extent; (2) Games that demand more cognitive function seem more beneficial than those based on repetitive aerobic exertion to improve fundamental motor skills; (3) The jumping/strength exercises may cause benefits in bone area and bone mineral density, while flexibility and balance may reduce the risk of muscle injury; and (4) Programming a greater dose of moderate-to-vigorous physical activity seems to be related to positive effects in core executive function and academic performance. Additionally, providing information and involving the social environment may enhance the positive effects. [ABSTRACT FROM AUTHOR]

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Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to investigate the potential cardioprotective effects of moderate and high-intensity aerobic interval training (MIIT and HIIT) preconditioning. The focus was on histological changes, pro-oxidant-antioxidant balance, autophagy initiation, and apoptosis in myocardial tissue incited by isoproterenol-induced pathological cardiac remodeling (ISO-induced PCR). Male Wistar rats were randomly divided into control (n = 6), ISO (n = 8), MIIT (n = 4), HIIT (n = 4), MIIT + ISO (n = 8), and HIIT + ISO (n = 8) groups. The MIIT and HIIT protocols were administered for 10 weeks, followed by the induction of cardiac remodeling using subcutaneous injection of ISO (100 mg/kg for two consecutive days). Alterations in heart rate (HR), mean arterial pressure (MAP), rate pressure product (RPP), myocardial oxygen consumption (MVO2), cardiac hypertrophy, histopathological changes, pro-oxidant-antioxidant balance, autophagy biomarkers (Beclin-1, Atg7, p62, LC3 I/II), and apoptotic cell distribution were measured. The findings revealed that the MIIT + ISO and HIIT + ISO groups demonstrated diminished myocardial damage, hemorrhage, immune cell infiltration, edema, necrosis, and apoptosis compared to ISO-induced rats. MIIT and HIIT preconditioning mitigated HR, enhanced MAP, and preserved MVO2 and RPP. The pro-oxidant-antioxidant balance was sustained in both MIIT + ISO and HIIT + ISO groups, with MIIT primarily inhibiting pro-apoptotic autophagy progression through maintaining pro-oxidant-antioxidant balance, and HIIT promoting pro-survival autophagy. The results demonstrated the beneficial effects of both MIIT and HIIT as AITs preconditioning in ameliorating ISO-induced PCR by improving exercise capacity, hemodynamic parameters, and histopathological changes. Some of these protective effects can be attributed to the modulation of cardiac apoptosis, autophagy, and oxidative stress. [ABSTRACT FROM AUTHOR]

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to determine changes in the kinematics of sprint steps based on progressive muscular fatigue during high-intensity 350-m and 500-m trials. Twelve elite healthy male 400-m sprinters with a minimum of six years of regular sprint training experience were recruited. They were divided into two groups for the experiment: a 350-m and a 500-m trial group. Time and kinematics of sprinting step motion for specific segments, i.e., starting to final stages of each trial, were obtained using the Opto Jump-Microgate optical measurement system. The starting phase of each sprint was defined as the section without muscular fatigue (noF), and the final phase was the sprint under muscular fatigue (onF). Each last 25 m of the 50-m evaluated section containing ten complete running steps was selected for detailed statistical analysis. Various patterns of temporal and spatial variables of sprinting efforts were observed between 350-m and 500-m trials. Each trial result was influenced by significant individual changes (p < 0.05). All variables indicated that the two distances differed significantly in terms of running kinematics. This was confirmed by significant differences in the mean step frequency (p < 0.001), which presented a difference of 11.75%, and the mean step speed (p < 0.001). As a result of these changes, a hierarchical intermittent endurance training pattern was defined. The research concluded that special endurance (intermittent sprints) based on 350 m differed significantly in kinematics from sprints over 500 m. Therefore, it should be assumed that the distance of 350 m is more similar in its kinematics to the 400-m competition. This should encourage coaches and athletes to apply a 350-m distance in training developing special endurance, especially in the pre-competitive and competitive periods. [ABSTRACT FROM AUTHOR]

Abstract Objective Myocardial infarction (MI) -induced cardiac dysfunction can be attenuated by aerobic exercises. This study explored the mechanism of interval training (IT) regulating cardiac function in MI rats, providing some theoretical basis for clarifying MI pathogenesis and new ideas for clinically treating MI. Methods Rats were subjected to MI modeling, IT intervention, and treatments of the Transforming growth factor-β1 (TGF-β1) pathway or the nod-like receptor protein 3 (NLRP3) activators. Cardiac function and hemodynamic indicator alterations were observed. Myocardial pathological damage and fibrosis, reactive oxygen species (ROS) level, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities, MDA content, inflammasome-associated protein levels, and inflammatory factor levels were assessed. The binding between TGF-β1 and receptor was detected. Results MI rats exhibited decreased left ventricle ejection fraction (LVEF), left ventricle fractional shortening (LVFS), left ventricular systolic pressure (LVSP), positive and negative derivates max/min (dP/dt max/min) and increased left ventricular end-systolic pressure (LVEDP), a large number of scar areas in myocardium, disordered cell arrangement and extensive fibrotic lesions, increased TGF-β1 and receptor binding, elevated ROS level and MDA content and weakened SOD, CAT and GSH-Px activities, and up-regulated NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC) and cleaved-caspase-1 levels, while IT intervention caused ameliorated cardiac function. IT inactivated the TGF-β1 pathway to decrease oxidative stress in myocardial tissues of MI rats and inhibit NLRP3 inflammasome activation. Activating NLRP3 partially reversed IT-mediated improvement on cardiac function in MI rats. Conclusion IT diminished oxidative stress in myocardial tissues and suppressed NLRP3 inflammasome activation via inactivating the TGF-β1 pathway, thus improving the cardiac function of MI rats.

Purpose:Quercetin is effective in the rehabilitation and treatment of apoptosis caused by cardiac ischemia, however, due to its low solubility in water, it is not suitable for clinical application, which can be improved by turning it into nanoparticles. The present study was designed to determine the effect of liposome nanoparticles with quercetin on apoptotic indices P38 and MK2 and its mechanisms in the rehabilitation of ischemic heart damage in rats.Methods:30 rats weighing 250±20 grams (aged 6-8 weeks) were randomly divided into five groups (healthy, sick, sick+supplement, sick+exercise and sick+exercise+supplement). Myocardial infarction was performed with isopronalin as a subcutaneous injection. Supplemental gavage was performed after training (8 sessions of aerobic training including: 5 days of training per week, which includes 7 intervals) and it was performed with a dose of 10 mg/kg of body weight of mice in the supplement receiving groups for eight weeks in the supplement receiving groups 48 hours after the last training session. The expression level of P38 and MK2 genes was measured by Real-Time PCR method. Data analysis was done with one-way analysis of variance, ANOVA, and Tukey's test at a significance level of p

Purpose: This study aimed to examine the impact of supra-maximal interval training (SMIT) and high-intensity interval training (HIIT) on cardiac auto-regulation response. Methods: Physically active young adults volunteered to participate in the study with a randomized cross-over counterbalanced design (N = 12). HIIT sessions consisted of 20 bouts of 10 s of exercise followed by 50 s of recovery, totaling 20 min at two different intensities; "all-out (SMIT)" vs. "115–130% Wmax (HIIT)". The cardiac auto-regulation included heart rate variability (HRV) and vascular function. HRV and vascular function were measured at baseline and five different time points after acute exercise. Results: The SMIT was higher in workload (31%), peak heart rate (28%), and rate of perceived exertion (40%) compared with HIIT (all p < 0.001). The R-R interval, NN50, and pNN50 measured until 60 min after acute exercise was higher in the HIIT compared with SMIT (all p < 0.05). The SMIT elicited a greater shift in ln LF/HF ratio immediately after acute exercise (3802%, p < 0.01) and induced a decrease in bilateral ba-PWV at the time point 5 min after acute exercise, persisting until 65 min after (p < 0.05). Yet, HIIT showed no change over time in the frequency domain of HRV and blood vascular tone after cessation of acute exercise. Conclusion: Our findings confirmed that SMIT is a more potent modulator of the autonomic nervous system compared with HIIT. Further study is needed to monitor through complete recovery to baseline, to understand acute cardiac auto-regulation response after cessation of various exercise intensities identical interval training protocol. [ABSTRACT FROM AUTHOR]

This study aimed to identify the optimal surface for sprint interval training to maximize transfer effects on physical performance measures on the grass pitch. Using a randomized controlled trial design, 40 collegiate female soccer players were equally assigned to three experimental groups performing short sprint interval training (SSIT: 4 sets of 10 repetitions with 5 seconds all-out running, with a 50-second recovery period between each effort and a 3-minute rest interval between sets) on SAND, GRASS, LAND, and a control group. Before and after a 7-week training period, participants underwent a series of field-based tests to evaluate countermovement jump (CMJ), 20-m linear sprint, Illinois change of direction (CoD) speed, Yo-Yo IR1, 2.4 km time trial, and maximal kicking distance (MKD) performance. A two-way analysis of variance with repeated measures was conducted on the data, along with Bonferroni post hoc testing. After the intervention, the control group did not show any changes, while the SAND, GRASS and LAND training groups demonstrated improvements (p = 0.001) in their performance as follows: CMJ (effect size [ES] = 1.21, 0.97, 0.64), 20-m linear sprint (ES = -0.81, -0.55, -0.41), Illinois CoD (ES = -0.72, -0.79, -0.41), Yo-Yo IR1 (ES = 1.86, 1.19, 1.12), 2.4 km time trail (ES = -0.82, -0.62, - 0.49), and MKD (ES = 0.60, 0.90, 0.72), respectively. Comparative analysis of SAND, GRASS, and LAND revealed that performing SSIT on SAND results in a significantly greater gain in CMJ than LAND (p = 0.041). Analyzing individual responses to training interventions indicated that the training surface had a favorable influence on CMJ (SAND vs. LAND, p = 0.009), but on other variables no statistically significant (p > 0.05) differences were observed. Considering these findings, it is advised that strength and conditioning coaches use the SAND surface as the initial choice for SSIT sessions regarding greater gains (i.e., ES) in performance. This recommendation aims to facilitate more favorable transfer in physical fitness adaptation on a soccer grass pitch. In case of unavailability of SAND surface, GRASS surface would be a suitable alternative to enhance the physical fitness of collegiate female soccer players. [ABSTRACT FROM AUTHOR]

The primary aim of the present investigation was to compare the acute physiological and perceptual responses between two modes of interval training using a randomized crossover design. More specifically, eleven young adult participants (23 ± 4 years, 77 ± 13 kg, 178 ± 7 cm) performed two protocols: one composed of whole-body calisthenics exercises and another on a cycle ergometer. Both protocols encompassed eight 20 s bouts at intensities equivalent to all-out (HIIT-WB) and 170% of the maximal power output (HIIT-C), respectively, interspersed with 10 s of passive rest. The peak and average heart rate, the rating of perceived effort, and blood lactate, creatine kinase, and lactate dehydrogenase concentrations were measured. Aside from blood lactate (HIIT-WB = 9.4 ± 1.8 mmo/L; HIIT-C = 12.5 ± 2.5 mmol/L, p < 0.05) and the rating of perceived exertion (HIIT-WB = 8.8 ± 0.9; HIIT-C = 9.6 ± 0.5, p < 0.05), physiological responses did not significantly differ between protocols (all p > 0.05), with high average heart rate values (HIIT-WB = 86 ± 6% HRmax; HIIT-C = 87 ± 4% HRmax) and a low magnitude of muscle damage, as inferred by CK and LDH concentrations (HIIT-WB = 205.9 ± 56.3 and 203.5 ± 72.4 U/L; HIIT-C = 234.5 ± 77.1 and 155.1 ± 65.3 U/L), respectively. It can be concluded that both protocols elicit vigorous heart rate responses and a low magnitude of muscle damage and, therefore, appear as viable alternatives to improve aerobic fitness. The inclusion of a whole-body HIIT protocol may be an interesting alternative for training prescription in relation to more common interval training protocols. [ABSTRACT FROM AUTHOR]