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Purpose: Long-distance running performance has been reported to be associated with sprint performance in highly trained distance runners. Therefore, we hypothesized that sprint training could enhance distance running and sprint performance in long-distance runners. This study examined the effect of 6-week sprint training on long-distance running and sprint performance in highly trained distance runners. Methods: Nineteen college runners were divided into control (n = 8) and training (n = 11) groups. Participants in the training group performed 12 sprint training sessions in 6 weeks, while those in the control group performed 12 distance training sessions. Before and after the interventions, maximal oxygen uptake ( V ˙ O 2 max), O2 cost during submaximal running (290 m·min−1 and 310 m·min−1 of running velocity), and time to exhaustion (starting at 290 m·min–1 and increased 10 m·min–1 every minute) were assessed on a treadmill. Additionally, the 100-m and 400-m sprinting times and 3000-m running time were determined on an all-weather track. Results: In the control group, no measurements significantly changed after the intervention. In the training group, the time to exhaustion, 100-m and 400-m sprinting times, and 3000-m running time improved significantly, while V ˙ O 2 max and O2 cost did not change. Conclusions: These results showed that 6-week sprint training improved both sprint and long-distance running performance in highly trained distance runners without a change in aerobic capacity. Improvement in the time to exhaustion without a change in V ˙ O 2 max suggests that the enhancement of long-distance running performance could be attributable to improved anaerobic capacity. [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]

Ski-orienteering, which combines cross-country skiing with orienteering, dates back to the late 1800s, with the first World Championships in 1975. While researchers have explored the physiological and biomechanical determinants of success in cross-country skiing and orienteering separately in detail, scientific knowledge concerning ski-orienteering remains limited. Based on the information that is presently available together with interviews with elite ski-orienteers, we explore here for the first time the historical development, physiological, biomechanical, and psychological demands, certain training strategies, and future prospects and challenges associated with this sport, including its potential to become an Olympic event. A demanding endurance sport (with racing times of 12–120 min), ski-orienteering requires both considerable aerobic and anaerobic capacity, as well as well-trained upper and lower body muscles. In addition, ski-orienteering demands advanced skiing technique on various types of terrain, with frequent changes between sub-techniques, on both wide and narrow tracks and with numerous turns on downhill terrain. Moreover, success in this sport requires accurate and rapid orienteering—the ability to navigate a complex network of ski tracks with numerous intersections/crossings in a manner designed to pass the multiple control points in the order indicated on the map as rapidly as possible, i.e., advanced spatial cognition and highly developed navigational skills. Thus, ski-orienteering requires training designed to improve both relevant physiological characteristics and orienteering skills, which should become the focus of future interdisciplinary research on this complex sport. [ABSTRACT FROM AUTHOR]

Objective: To establish the effect of high-intensity and progressive volume resistance training (HIRT), on general health, functional, mental status, and quality of life (QOL) indicators in people with spinal cord injury (SCI). Methods: The sample consisted of five people with SCI of both sexes, aged 46.2 ± 13.9 years, submitted to 12 weeks of HIRT, twice a week. We analyzed before and after the 12 weeks of intervention: body composition, muscle strength, functional status, perception of mental status, and QOL, using the following tests: dual-energy X-ray densitometry, 1RM, isometry of biceps, elbow flexion, Wingate, zigzag, medicine ball pitch, Beck inventory (anxiety, depression, and mental disorder) and SF-36. Results: The results pointed to an increase in the training load, the total bone mineral content (p = 0.043), the muscle power at 80% of 1RM (p = 0.043), the functional state (anaerobic power [MD = 6.81%; p = 0.043] and explosive strength [mean difference (MD) = 30.57%; p = 0.043] of the shoulder girdle muscles), the mental state (MD = 71.46%; p = 0.006) and finally, improvement in QOL, especially in the functional (MD = 60.87%; p = 0.006) and social aspects (MD = 44.44%; p = 0.006). Conclusions: HIRT can improve or maintain body composition, developing muscle power, anaerobic power, and explosive strength of the upper limbs that will impact functional capacity, promoting greater autonomy, with consequent reflex in improving mental state and of the QOL of the person with SCI. [ABSTRACT FROM AUTHOR]

To synthesize evidence about physical fitness levels in children with developmental coordination disorder (DCD) compared with typically developing (TD) children. We searched four databases (PubMed, Scopus, Web of Science, and PsycINFO) for cross-sectional, case-control, and cohort studies comparing physical fitness between children with and without DCD. We assessed the methodological quality of the studies with the Newcastle-Ottawa Scale (NOS). We calculated Cohen's d effect sizes to provide clinical evidence of group differences in aerobic capacity, anaerobic capacity, muscle strength, body composition and flexibility. We included 32 studies for qualitative synthesis after applying eligibility criteria. All selected studies ranged from moderate to high research quality. Effect sizes in favor of typically developing children over children with DCD were large for aerobic capacity (d = 1.15), anaerobic capacity (d = 0.90), and muscle strength (d = 0.79), and small for body composition (d = 0.43) and flexibility (d = 0.21) outcomes. Children with DCD presented significantly lower physical fitness than their typically developing peers, particularly in aerobic and anaerobic capacity and in muscle strength. [ABSTRACT FROM AUTHOR]

BackgroundMethodsResultsConclusionWhole body vibration (WBV) exercise is a therapy used for individuals with low tolerance to conventional exercises, such as patients with chronic obstructive pulmonary disease (COPD). This study aimed to assess the impact of WBV exercise on the functional capacity, muscle strength, and health-related quality of life (HRQoL) in severe COPD patients.Studies published until March 2024 were reviewed, encompassing randomized clinical trials (RCTs) without temporal or linguistic constraints, comparing WBV exercise with other interventions. The PubMed/MEDLINE, Scopus, Cochrane Airways Trials Register, and CINAHL databases were queried. The Revised Cochrane risk-of-bias tool for randomized trials 2.0A was employed for quality assessment.Among 351 screened studies, 7 met the criteria, totaling 356 participants (WBV group, n = 182; control group, n = 174). Meta-analysis revealed a significant mean difference of 41.36 m [95%CI (13.28–69.44); p = .004] in the 6-minute walk test distance favoring the WBV group for functional capacity. Lower limb muscle strength improved in 57.14% of included studies. HRQoL meta-analysis demonstrated a 1.13-point difference [95%CI −1.24-3.51; p = .35] favoring WBV, although group differences were not significant. A mean difference of 2.31 points favored the control group in health condition [95%CI (−1.32–5.94); p = .021].WBV exercise is recognized as a promising therapeutic modality for severe COPD patients, notably enhancing functional capacity. Although heterogeneous study protocols weaken the evidence for clinically relevant outcomes, improvements in lower limb muscle strength and HRQoL were also observed, differences between groups were not significant. [ABSTRACT FROM AUTHOR]

Anaerobic co‐digestion using an anaerobic dynamic membrane bioreactor (AnDMBR) can separate the sludge retention time and hydraulic retention time, retaining the biomass for efficient degradation and the use of less expensive large pore‐size membrane materials and more sustainable dynamic membranes (DMs). Therefore, anaerobic co‐digestion of toilet blackwater (BW) and kitchen waste (KW) using an AnDMBR was hypothesized to increase the potential for co‐digestion. Here, the efficiency and stability of AnDMBR in anaerobic co‐digestion of toilet BW and KW were investigated. DM morphology and structural characteristics, filtration properties, and composition, as well as membrane contamination and membrane regeneration mechanisms, were investigated. Average daily biogas yields of the reactor in two membrane cycles before and after cleaning were 788.67 and 746.09 ml/g volatile solids, with average methane content of 66.64% and 67.27% and average COD removal efficiencies of 82.03% and 80.96%, respectively. The results showed that the bioreactor obtained good performance and stability. During the stabilization phase of the DM operation, the flux was maintained between 43.65 and 65.15 L/m2/h. DM was mainly composed of organic and inorganic elements. Off‐line cleaning facilitated DM regulation and regeneration, restoring new Anaerobic morphology and structure. Practitioner Points: High efficiency co‐digestion of BW and KW was realized in the DMBR system.Average daily biogas yields before and after membrane cleaning were 788.67 and 746.09 ml/g volatile solids.Off‐line cleaning facilitated DM regulation and regeneration as well as system stability.The flux was maintained between 43.65 and 65.15 L/m2/h during operation. [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]

Mental fatigue has been studied extensively in relation to its impact on aerobic-, strength-, and motor-based tasks, but anaerobic power-based tasks have received limited attention. Interdisciplinary research investigating the underlying mechanisms by which mental fatigue influences physical performance has been called for. In two studies, the effects of mental fatigue on maximal power jump and endurance jump performance as well as kinetics and kinematics during jump performance were examined. Samples of collegiate volleyball players (Study 1; N = 14) and recreationally active students (Study 2; N = 27) completed two 30 min experimental manipulations (high vs. low cognitive control exertion) before performing three maximal power squat jumps followed by 15 repeated countermovement jumps, with measurements of kinetics and kinematics. For Study 1, the maximal power performance was significantly lower under a mentally fatigued condition, but no differences were observed for repeated jump performance, which may have been attributable to alterations in jump mechanics. For Study 2, no between-condition differences were observed for the maximal power performance, although repeated jump performance was significantly lower under a mentally fatigued condition. Collectively, these findings suggest that the impacts of mental fatigue on power-based performance tasks may depend on the task demands as well as the training status of the individual. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to investigate the effect of pre-exercise whole-body cryotherapy (WBC) on muscle damage indicators following eccentric treadmill exercise in young women. Methods: Twenty-seven participants underwent two 1-h downhill treadmill runs, replicating 60% of their maximal oxygen uptake, with a 4-week intermission for recovery and treatment application. In this intermission, one group underwent 20 sessions of WBC, delivered five times a week at -120°C for 3 min each, while the comparison group received no such treatment. Markers of muscle injury--serum myoglobin concentration, creatine kinase and lactate dehydrogenase activity and also uric acid, and cell-free DNA concentration--were measured before and after downhill runs. Results: The study observed a notable reduction in post-exercise myoglobin and CK levels in the WBC group after the second running session. Discussion: The results suggest that WBC can have a protective effects against muscle damage resulting from eccentric exercise. [ABSTRACT FROM AUTHOR]

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During high-intensity (HI) exercise, metabolic acidosis significantly impairs exercise performance. Increasing the body's buffering capacity through training and exogenous intake of alkalizing supplements may improve highintensity performance. Manipulating water and diet intake may influence the acid-base balance. The aim of this study was to determine the effects of mineral water rich in bicarbonate ions (STY) or placebo water (PLA) on circulating biomarkers and anaerobic performance and to verify whether alkalizing (ALK) or acidizing (ACI) diet would modulate these effects. Twenty-four athletes, assigned either to ALK (n = 12) or ACI (n = 12) diet for four weeks, completed a 1-min rowing Wingate Test in a double-blind and randomized trial after one week of daily hydration (1.5 to 2L/d) with either STY or PLA. Blood samples were taken before and after each test, and urine samples were collected each week. Chronic consumption of bicarbonate-rich water significantly impacted resting urinary pH irrespective of alkalizing or acidizing dietary intake. STY induced a significant increase in blood pH, lactate, and HCO3- ion concentration postexercise compared to PLA. Similar changes were observed when STY was associated with the ALK diet. In contrast, STY combined with the ACI diet only significantly affected urine pH and peak blood lactate compared to PLA (p < 0.05). No effect of bicarbonate-rich water was reported on anaerobic performance (p > 0.05). Our results suggest that consumption of bicarbonate-rich water alters acid-base balance during a warm-up and after HI exercise, could potentiate beneficial effects of an alkalizing diet on the acid-base balance after HI exercise, and reduces the acid load induced by an acidifying diet. [ABSTRACT FROM AUTHOR]

Background/Objectives: Due to the character of the taekwondo, the adenosine triphosphate–phosphocreatine system provides the energy for each kick, the glycolytic system supports the repeated execution of kicks, and the aerobic system promotes recovery between these movements and the bout. Therefore, taekwondo athletes require high explosive power and anaerobic capacity in order to carry out sustained and powerful attacks. So, the purpose of this study is to compare the effects of APRE and VBRT on lower-limb explosive power and anaerobic capacity in college taekwondo players. Methods: A total of 30 taekwondo players completed an 8-week training intervention with autoregulatory progressive resistance exercise (APRE; n = 15) and velocity-based resistance training (VBRT; n = 15). Testing included the one-repetition maximum squat, countermovement jump (CMJ), taekwondo anaerobic intermittent kick test (TAIKT), and 30-s Wingate anaerobic test (WAnT). Results: (1) Intragroup comparisons revealed significant effects for one-repetition maximum squat, peak power of CMJ (CMJPP), relative peak power of CMJ (CMJRPP), and total number of TAIKT (TAIKTTN) in both the APRE and VBRT groups. The VBRT group exhibited small effect sizes for time at peak power of WAnT (WAnTPPT) and moderate effect sizes for peak power of WAnT (WAnTPP), relative peak power of WAnT (WAnTRPP), and fatigue index of TAIKT (TAIKTFI), whereas the APRE group exhibited small effect sizes for TAIKTFI. (2) Intergroup comparisons revealed no significant effects in any of the results. However, VBRT demonstrated a moderate advantage in WAnTPP and WAnTRPP, whereas APRE had a small advantage in CMJPP and CMJRPP. Conclusions: These findings suggest that APRE improved explosive power (CMJPP and CMJRPP) more, whereas VBRT improved anaerobic power output (WAnTPP and WAnTRPP) more. Both methods were found to have similar effects in improving the anaerobic endurance (WAnTPPT and TAIKTTN) and fatigue index (power drop of WAnT and TAIKTFI).

Introduction: This study presented a novel approach to predict future front crawl swimming world records (WRs) by employing a methodology that integrated performance data from both running and front crawl swimming. Methods: By extracting the top one running and swimming performances from 1995 to 2023 and applying a model that correlates physiological characteristics such as maximum aerobic power, anaerobic capacity, the decrement in maximum power with prolonged effort, and performance speed and duration, it was possible to project the potential record-breaking performances in 2024 across various swimming distances for both male and female athletes. Furthermore, this approach was expected to be less susceptible to the influence of the full-body swimsuit era, which may have disrupted the typical trajectory of swimming performance progression. Results: The average relative error between the top one and estimated speeds in front crawl swimming (50-1,500 m, from 1995 to 2023, and for male and female) was 0.56% ± 0.17%. For male, WR in longer distances have been predicted with new WR in the 400 and 800 m. A more ambitious prediction was noted among female, with twice as many WR as among male illustrated by new WR in the 50, 200, 400 and 800 m. Discussion: This study illustrated that the utilization of a prediction model based on physiological parameters yielded plausible time estimates. Additionally, the research accentuated the ongoing trajectory of surpassing existing WR into 2024, illustrating the competitive zeal fueled by an emerging framework of exceptional swimmers. [ABSTRACT FROM AUTHOR]

Low‐load resistance exercise (LLRE) to failure can increase muscle mass, strength, endurance, and mitochondrial oxidative capacity (OXPHOS). However, the impact of adding blood flow restriction to low‐load resistance exercise (LLBFR) when matched for volume on these outcomes is incompletely understood. This pilot study examined the impact of 6 weeks of single‐legged LLBFR and volume‐matched LLRE on thigh bone‐free lean mass, strength, endurance, and mitochondrial OXPHOS. Twenty (12 males and 8 females) untrained young adults (mean ± SD; 21 ± 2 years, 168 ± 11 cm, 68 ± 12 kg) completed 6 weeks of either single‐legged LLBFR or volume‐matched LLRE. Participants performed four sets of 30, 15, 15, and 15 repetitions at 25% 1‐RM of leg press and knee extension with or without BFR three times per week. LLBFR increased knee extension 1‐RM, knee extension endurance, and thigh bone‐free lean mass relative to control (all p < 0.05). LLRE increased leg press and knee extension 1‐RM relative to control (p = 0.012 and p = 0.054, respectively). LLRE also increased mitochondrial OXPHOS (p = 0.047 (nonparametric)). Our study showed that LLBFR increased muscle strength, muscle endurance, and thigh bone‐free lean mass in the absence of improvements in mitochondrial OXPHOS. LLRE improved muscle strength and mitochondrial OXPHOS in the absence of improvements in thigh bone‐free lean mass or muscle endurance. [ABSTRACT FROM AUTHOR]

Objective: To analyze the physical fitness characteristics of elite freestyle skiing aerials athletes, thereby enhancing the understanding of exercise physiologists, sports scientists, and coaches regarding the demands in this discipline. Methods: After health screenings, 29 athletes from the Chinese National Freestyle Skiing Aerials Team were divided into elite and general groups, including males and females. Physical fitness indexes were determined through literature reviews, expert interviews, and the Delphi method, followed by physical fitness tests assessing body morphology, physiological function, and physical quality. Data normality was verified using the Shapiro-Wilk test. Differences between the two groups were then evaluated using independent sample t-tests or Mann-Whitney U tests, after which effect sizes were calculated to assess the magnitude of the differences. Results: Significant body morphology differences were noted between elite and general groups in fat-free body weight, leg, and waist circumferences (P < 0.05). Male athletes in the elite group exhibited a significantly lower percentage of body fat (P < 0.05), whereas the reduction in body fat percentage among female elite athletes was not statistically significant. In terms of physiological function assessment, elite athletes demonstrated superior performance in both maximum anaerobic capacity and relative maximum anaerobic capacity compared to their counterparts in the general group (P < 0.05). Notably, the difference in maximum anaerobic capacity was highly significant among male athletes (P < 0.01), and the relative maximum anaerobic capacity among female athletes was also markedly significant (P < 0.01). Regarding physical quality indexes, elite athletes outperformed those in the general group in all aspects except for the quick v-up and 12-minute run tests (P < 0.05 or P<0.01). Conclusion: Elite athletes exhibit superior physical fitness characteristics compared to general athletes, attributable to differences in age, years of training, and their participation in ongoing specialized physical training within structured, cyclical programs. Specifically, elite athletes demonstrated higher fat-free body weight, larger waist and leg circumferences in terms of body morphology. Particularly, male athletes showed a trend towards lower body fat percentage. Physiologically, they exhibited stronger anaerobic metabolism capabilities. In terms of physical quality, elite athletes displayed superior limb strength, lower limb explosive power, and specialized core strength, along with better speed, agility, and overall coordination. [ABSTRACT FROM AUTHOR]

The popularity of surfing has increased exponentially, reaching its recent debut in the Olympic Games. However, surfing suffers from a relative immature technological market, while in other sports some technologies such as global navigation satellite systems (GNSSs) have become an essential work material for strength and conditioning and head coaches. This article aims to systematically review surfers' time–motion demands based on GNSSs. A systematic review of relevant articles was carried out using five main databases (PubMed, ProQuest Central, SCOPUS, SPORTDiscus, and FECYT (Web of Sciences, CCC, CIDW, KJD, MEDLINE, RSCI, and SCIELO)) until 23 March 2024. From the 238 studies initially found, 9 were included in the qualitative synthesis. In these, GNSS devices were employed with male (n = 143) and female (n = 28) surfers from different levels during competition and training situations. The studies show that the intermittent nature of the sport is evident, with substantial periods spent paddling and waiting punctuated by relatively brief high-intensity efforts when riding waves at high speeds. Notable differences emerged between competition and training demands, suggesting potential mismatches in how athletes currently prepare compared to event requirements. These novel insights allow quantifying surfing's harsh physiological requirements and could guide conditioning practices to better meet the sport's unique characteristics across populations. Therefore, training should emulate the lengthy aerobic capabilities needed for the paddling volumes observed, while also targeting the anaerobic systems to meet the repeated high-intensity surf riding efforts. However, inconsistencies in methods and reporting practices limit direct comparisons and comprehensive profiling of the sport's physical characteristics. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the reliability of a single-trial determination of maximal accumulated oxygen deficit (MAOD) achieved via the aid of perceptually-regulated incremental exercise. Methods: 14 trained male cyclists (age: 45 ± 8 yrs; height: 1.82 ± 0.06 m; mass: 79.7 ± 6.7 kg; $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max : 4.09 ± 0.57 L·min−1) performed three trials of a submaximal incremental cycling test followed by a test to exhaustion at 116% of predicted $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max . The intensity for each stage of the incremental test was regulated by participants to elicit perceived exertion levels of 9–15 on the Borg (6–20) scale. Linear regression was used to estimate $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max at a perceived exertion level of 19. MAOD was calculated from the difference between predicted and actual oxygen demand in the test to exhaustion, reported in oxygen equivalents (O2 eq). A separate incremental test was used to measure $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max directly. Results: Correlation coefficients between perceived exertion and $${\dot{\rm{V}}{\rm{O}}_{2}}$$ V ˙ O 2 across trials were strong (r ≥0.99), and there were no between-trial differences in predicted $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max (4.03 ± 1.04, 3.76 ± 0.53, and 3.69 ± 0.64 L·min−1, respectively; p =.142) or MAOD (2.75 ± 2.28, 2.50 ± 1.53, and 2.93 ± 1.40 L O2 eq, respectively; p =.633). Nevertheless, the coefficients of variation for predicted $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max (14.2%) and MAOD (142.8%) were poor. Conclusions: The prediction of $${\dot{\rm{V}}{\rm{O}}_{2{\rm{max}}}}$$ V ˙ O 2 max from perceptually-regulated exercise displays a level of test-retest reliability which prevents its use as a means of evaluating MAOD reliably in a single-trial. [ABSTRACT FROM AUTHOR]

The agri-food industry, produces organic residues that could be reused as fertilizer, thereby allowing the recycling of nutrients for crops and the replacement of mineral fertilizers. In this context, here we examined the capacity of anaerobic digestates and mixed residues (digestates plus spent mushroom substrates) to supply nutrients to lettuce (Lactuca sativa L.) grown in a greenhouse experiment. Moreover, the potential leaching of nutrients into the soil was evaluated in a column assay. The results obtained from organic residues treatments were then compared to those achieved in soil treated with mineral fertilizer and in untreated soil. Digestates treatments minimized the potential risk of nitrate (NO3−) leaching by allowing the slow release of NO3− maintaining crop yield. Given our observations, this type of organic residues emerges as an alternative to mineral fertilizer. The loss of NO3−-N from the total amount of N applied reached ∼3% in the mixed residues treatments, 36–46% in the digestate treatments, and 68% in the mineral fertilizer treatment. The mixed treatments showed low available N content as a result of immobilization in the soil, which is a limiting factor for crop production. Moreover, the organic residues treatments had no negative effect on lettuce seed germination or plant growth with respect to parameters such as chlorophyll, total polyphenols, and heavy metals in aerial biomass. The findings reported herein contribute to a better understanding of nutrient availability provided by organic residues materials and the capacity of these amendments to replace mineral fertilizers and avoid nutrient loss by leaching. Digestate treatments showed a similar capacity to maintain lettuce production as mineral fertilizer. Mixed treatments did not provide mineral N for the crop by N immobilization in soil. Nitrate loss when organic residues were applied was lower than for the mineral fertilizer treatment. Soil amendment with organic residues has no negative effects on lettuce yield. Digestates emerge as an alternative to mineral fertilizers for lettuce production, reducing soil nutrient loss. [ABSTRACT FROM AUTHOR]

Purpose: The practice of Functional Fitness Training (FFT) combines aerobic and muscle strength exercises that can lead to adaptations different from those observed with the isolated practice of Strength Training (ST). Thus, this study aimed to compare lower limb power and hypertrophy in different muscle portions between FFT and ST practitioners. Methods: In this cross-sectional study, men experienced (≥2 years) in FFT (n = 8; 27 ± 4.6 years) and ST (n = 8; 29.13 ± 6.12 years) participated. Additionally, physically active men were recruited for the control group (n = 8; 25 ± 8.24 years). For muscle power, jump height and peak power output (PPO) normalized by body mass were evaluated, and for hypertrophy, the cross-sectional area (CSA) was evaluated in 4 different portions of the vastus lateralis with the aid of B-mode ultrasound. Results: It was observed that the CSA did not differ between the FFT and ST groups, and showed higher values in relation to the control group. Jump height was higher (p = 0.003) for the FFT group (53.5 ± 2.4 cm) compared to the control group (45.7 ± 3.6 cm), and did not differ in relation to the ST group (50.8 ± 5.7 cm; p = 0.058). PPO showed no statistical difference (p = 0.39) between groups (control, 50.5 ± 6 W kg−1; FFT, 54.1 ± 5.8 W kg−1; ST, 50.6 ± 5.6 W kg−1). Conclusion: Vastus lateralis hypertrophy does not differ between men experienced in FFT and ST. The practice of these training methods does not seem to differ in relation to muscular power, although there are indications that those of FFT perform better than those of ST. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore the effects of a 7-week short sprint interval training (SSIT) with differing in programming volume-loads including progressive (P-SSIT) and nonprogressive (NP-SSIT) approaches on the immunoendocrine, physical fitness attributes and physiological parameters in male wrestlers during the pre-season. Thirty young freestyle wrestlers at the collegiate national-level were included in the study and were divided into three groups: P-SSIT (n = 10), NP-SSIT (n = 10), and an active control group (n = 10). The wrestlers engaged in their specific wrestling training three days weekly, while the P-SSIT and NP-SSIT groups underwent a 7-week SSIT, with scheduling in either progressed or nonprogressed volume-based overloads, three times per week. Before and after the intervention, various aspects of physical fitness (such as 20-m sprint, 4x9-m shuttle run, and maximal strength) and physiological parameters (including cardiorespiratory fitness and anaerobic power output), as well as immunoendocrine responses (such as immunoglobulin-A, testosterone, and cortisol) were measured. Following the training intervention, the control group did not show any significant changes in the variable measured; however, both the P-SSIT and NP-SSIT groups experienced significant improvements (p = 0.001) in physical fitness attributes and physiological parameters with effect sizes ranging from small to very large, and also more adaptive responses compared with control group (p < 0.05). In addition, there were no statistically significant changes observed among the P-SSIT and NP-SSIT groups in terms of immunoendocrine response to training, and physical fitness, as well as physiological parameters (p > 0.05). In conclusion, neither the progressed nor nonprogressed approaches of SSIT demonstrated superior effects on adaptations compared to one another. Therefore, it is recommended for strength and conditioning coaches in wrestling to incorporate both P-SSIT and NP-SSIT into their annual training plan, especially during the pre-season phase, to maximize the physical fitness and physiological parameters of their wrestlers while minimizing changes in immunoendocrine responses. [ABSTRACT FROM AUTHOR]

Background: Most human movements are supported by its functional capabilities of the anaerobic type, which is dominated by submaximal and maximal sports activities performed in a short time. Functional capabilities of the anaerobic type of man participate in most of his movement activities. Conditioned on adequate and extremely good interaction and functioning of the cardiovascular and respiratory systems, morphological status, metabolic processes, muscle structure, nutritional status, physical activity, etc. Purpose: The research was conducted in the conditions of the so-called field testing with the primary goal of assessing the acute state of anaerobic abilities of physical and sports students, by calculating the fatigue index (FI). Methods: The sample included 80 students of Physical and Sports Education, different geographical regions, average weight 77.88±8.49kg, age 20-23 years. The Running Anaerobic Sprint Test (RAST) was used to assess FI, and the basic statistical parameters were calculated. Results: The average value of the student’s leg power is 573.89 watts (378.42 watts vs. 817.99watts), and the recorded average (FI) of 8.35 watts/sec (3.97watts/sec. vs. 16.93watts/sec.). Conclusions: The obtained results confirmed the average values of anaerobic capacity which are suitable for the examined population of subjects, while the maximal the value of FI suggests a weaker state of the anaerobic capacity of the individuals (less tolerance to lactates). [ABSTRACT FROM AUTHOR]

Anaerobic digestion (AD) is a widely applied technology for renewable energy generation using biogas as energy vector. The existing microbial consortium in this technology allows for the use of several types of biomass as substrates. A promising alternative for the production of high-value products (e.g., mixed volatile fatty acids–VFAs, hydrogen) is the use of modified AD. There are several techniques to achieve this objective by modifying the operating conditions of the process. The literature has described the best AD routes for generating renewable energy or high-value products based on specific substrate types and operating conditions. Few studies have reported the integral fraction valorization of the AD process applying the biorefinery concept. This article provides an analysis of the different routes that favor the production of energy carriers and high-value products involving key issues related to operating conditions and substrates. Moreover, AD is addressed through the biorefinery concept. Finally, a case study is presented where renewable energy and mixed VFAs are generated by applying the biorefinery concept in a number of proposed scenarios using organic kitchen food waste (OKFW) as feedstock. The case study involves an experimental and simulation stage. Then, the economic feasibility of the proposed scenarios is evaluated. In conclusion, AD is a promising and economically feasible technology to produce valuable products from several types of waste materials. [ABSTRACT FROM AUTHOR]

Background and Aim: Today, training on various training surfaces is one of the most important concerns of coaches for improving sports performance, which has rarely been considered in sport teams. The purpose of this study was to investigate the effect of six-week of specific volleyball training on ground surfaces (concrete, floor and sand) on some selected factors of physical fitness in volleyball male players. Materials and Methods: Thirty-six male volleyball players (average age, 16.11±0.82 years) were purposefully selected and randomly divided into three training groups including training on concrete, floor, and sand surfaces. The repeated effort performance test (jump and real-time, time and ideal jump) with four repetitions and rest between repetitions at players' movement speed between 4 to 8 seconds was used. All tests were performed before and after the training programs. One-way analysis of variance and Tukey's tests were used at the significance level of p≤0.05. Results: Anaerobic power, explosive power (Jumping record) and time reduction in the repeated performance test significantly increased in the both sand and flooring groups compared to the concrete group. Moreover, agility and dynamic balance in the sand and flooring group had a significant decrease and increase, respectively, as compared to the concrete group. Additionally, dynamic balance showed more increased in the sand group than in the floor group. Conclusion: Specific volleyball exercises on sand compared to other surfaces by increasing training overload caused neuro-muscular adaptations and finally improved sports performance and physical fitness of volleyball players. Accordingly, coaches can use sand surfaces to maximize the benefits of training and prevent injury and pain to players. [ABSTRACT FROM AUTHOR]

The aim of the study was to detect the relationship of isocapnic buffering phase values with the values of both aerobic and anaerobic power. A total of 14 athletes, five females and nine males, with ages between 18 and 25 volunteered to participate in the present study. At the beginning, the values of height, body mass, and body fat ratio of the volunteers were collected as required. Then, a maximal exercise test was applied to the volunteers and during the test, the values of maximal oxygen consumption capacity (VO2max), amount of oxygen consumed (VO2), amount of carbon dioxide produced (VCO2), ventilatory threshold, respiratory compensation point, and maximal heart rate were determined. Isocapnic buffering and hypocapnic hyperventilation phases were determined from the ventilatory threshold and respiratory compensation point values. One week after the maximal exercise test, the Wingate anaerobic test was applied to the volunteers and anaerobic power values were calculated. A significant relationship was found between the values of isocapnic buffering and hypocapnic hyperventilation, and the values of maximal heart rate (beats/min), ventilatory threshold VO2 (ml/kg/min), ventilatory threshold heart rate (beats/min), ventilatory threshold speed (km/hour), respiratory compensation point heart rate (beats/min), and respiratory compensation point speed (km/hour) in both male and female volunteers. The findings collected hereby indicate that as the VO2max levels of athletes increase, both their cardiopulmonary data and anaerobic power values and also their ability to resist the intensity of exercises applied after entering anaerobic threshold, increase. [ABSTRACT FROM AUTHOR]

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The study assessed vastus lateralis oxygen desaturation kinetics (SmO2) in 32 male cyclists (16 Seniors, 16 Juniors) during a 30 s sprint, examining effects of age and performance. An incremental test was used to determine ventilatory thresholds (VT1, VT2) and maximal oxygen uptake (VO2kg), followed by a sprint test to evaluate anaerobic performance. Cyclists' performance phenotype was determined as the ratio of power at VT2 to 5 s peak sprint power. Juniors exhibited sprinter-like traits, excelling in all functional tests except for lactate levels post-sprint. SmO2 data showed no age-related or bilateral differences across participants. The combined mean response time (MRT) revealed stronger bilateral goodness of fit (R2 = 0.64) than individual time delay (TD) and time constant (τ). Higher VO2kg at VT2, peak power, and maximal uptake were linked to longer TD, while shorter TD correlated with higher lactate production and increased fatigue. Bilaterally averaged SmO2 kinetics distinguished between sprint and endurance athletes, indicating the potential to reflect the alactic anaerobic system's capacity and depletion. Age did not affect desaturation rates, but younger cyclists showed greater response amplitude, attributed to a higher initial baseline rather than maximal desaturation at the end of the exercise. [ABSTRACT FROM AUTHOR]

Lean body mass (LBM) is correlated with powerlifting performance in athletes competing in different bodyweight classes. However, it remains unknown whether changes in LBM are correlated with performance changes in powerlifters preparing for a competition. The aim of this study was to investigate the changes in LBM and performance in powerlifters preparing for a competition. Eight male powerlifters (age 31.7 ± 9.8 years, height 1.77 ± 0.06 m, weight 99.2 ± 14.6 kg) and three female powerlifters (age 32.7 ± 16.3 years, height 1.54 ± 0.06 m, weight 66.6 ± 20.9 kg) participated in the study. The athletes followed individualized periodized training programs for 12 weeks, aiming to maximize their performance for the national championship. The maximum strength (1-RM) in the squat, bench press, and deadlift, body composition, handgrip strength, anaerobic power, quadriceps' cross-sectional area and vastus lateralis muscle architecture were measured before and after the training period. Significant increases were found after the training period in the squat (5.8 ± 7.0%, p < 0.05), bench press (4.9 ± 9.8%, p = 0.05) and deadlift (8.3 ± 16.7%, p < 0.05). Significant correlations were found between the 1-RM and LBM before and after the training period (r > 0.75, p < 0.05). The changes in the 1-RM after the training intervention correlated with the changes in the total LBM (p < 0.05). These results suggest that individual changes in LBM due to systematic resistance training for a competition may dictate increases in the 1-RM strength in powerlifters. [ABSTRACT FROM AUTHOR]

This randomized, double-blinded, experimental study investigated the effects of a four-week daily pre-workout supplementation (200 mg caffeine, 3.3 g creatine monohydrate, 3.2 g β-alanine, 6 g citrulline malate, and 5 g BCAA) vs. placebo (isocaloric maltodextrin) on anaerobic (jumping, sprinting, agility, and the running-based anaerobic sprint test: RAST) and aerobic (Yo-Yo intermittent recovery test level 1) performance, as well as on body composition and selective muscle damage/health-related blood markers in well-trained basketball players during the in-season period. Eighteen basketball players (age: 24.4 ± 6.3 years, height: 185.7 ± 8.0 cm, weight: 85.7 ± 12.8 kg, body fat: 16.5 ± 4.2%) were randomly assigned into two groups: pre-workout supplement (PWS, n = 10) or placebo (PL, n = 8). PWS consumption increased aerobic performance (PWS: 8 ± 6%; PL: −2 ± 6%; p = 0.004) compared to PL. A significant decrease was observed in peak (F = 7.0; p = 0.017), average (F = 10.7; p = 0.005), and minimum power (F = 5.1; p = 0.039) following 4 weeks of supplementation in both groups. No other significant changes were observed between groups (p > 0.05). In conclusion, the consumption of the current PWS over a four-week period appears to positively influence the aerobic performance of well-trained basketball players during the in-season period. However, it does not appear to mitigate the observed decline in anaerobic power, nor does it affect performance in jumping, sprinting, and agility, or alter body composition or selective muscle damage/health-related blood markers. [ABSTRACT FROM AUTHOR]

Combat sports, encompassing a range of activities from striking and grappling to mixed and weapon-based disciplines, have witnessed a surge in popularity worldwide. These sports are demanding, requiring athletes to harness energy from different metabolic pathways to perform short, high-intensity activities interspersed with periods of lower intensity. While it is established that the anaerobic alactic (ATP-PC) and anaerobic lactic systems are pivotal for high-intensity training sessions typical in combat sports, the precise contribution of these systems, particularly in varied training modalities such as single (SMT) and intermittent (IST) forms of the 30-second Wingate test, remains inadequately explored. This study aims at comparing performance outputs, physiological responses and gender differences during the SMT and IST forms of the 30-second Wingate test. Thirty-three highly trained combat sports athletes (17 women, 16 men; 10 boxing, 8 wrestling, 8 taekwondo and 7 karate) randomly performed SMT and IST. The IST consisted of three 10-second all-out attempts separated by 30 seconds of passive recovery, whereas the SMT was a single 30-second maximal effort. Resting, exercise and post-exercise oxygen uptake and peak blood lactate value were used to determine the metabolic energy demands via the PCr-LA-O2 method. The findings showed that total metabolic energy expenditure (TEE), ATP-PCr system contribution and the output of mechanical variables were higher in the IST than in the SMT form (all p<0.001). In contrast, the contribution of glycolytic and oxidative systems was higher in the SMT form (all p<0.001). However, exercise form and gender interaction were not significant (p>0.05). In combat sports, performance is not only determined by physiological and technical skills but also by metabolic energy input and efficiency. Therefore, our results can provide a comparison regarding the effects of exercise type and gender on metabolic energy metabolism to design the training of combat sports athletes. [ABSTRACT FROM AUTHOR]

Purpose: Surgical site infection (SSI) is a serious complication after cranioplasty. Due to the relatively frequent occurrence of post-cranioplasty SSI, the utility of autologous bone flap swab cultures surrounding cryopreservation as a reliable predictor has been the subject of an ongoing debate. This bicentric study aims to contribute to this topic by conducting an in-depth analysis of bone flaps obtained via decompressive craniectomies. This study had three major aims: assessments of 1) bacterial contamination of bone flaps after decompressive craniotomy, 2) impact of cryoconservation on contamination rates and 3) potential effectiveness of anti-infective treatment to reduce the germ load prior to cranioplasty. Methods: Cryopreserved bone flaps from two centers were used. Microbiological cultivations of swabs prior to and after cryopreservation were taken and assessed for aerobic and anaerobic growth over a 14-day incubation period. Additionally, in a subset of bone flaps, swab testing was repeated after thorough rinsing with an anti-infectant (octenidine-phenoxyethanol) followed by saline. Results: All 63 bone flaps (patients median age at surgery: 59 years) were obtained via decompressive craniectomies. Swabs done prior to cryopreservation revealed a 54% infection rate with Propionibacterium acnes being the most common microorganism in 65% of those cases. After thorough disinfection of the preserved bone flaps, all but one case showed no bacterial growth in swab testing. Furthermore, no relevant risk factors for bacterial contamination could be identified. Conclusion: This retrospective study showed the common presence of bacterial growth in cryopreserved bone flaps before and after freezing. Rinsing with octenidine-phenoxyethanol and saline effectively prevented bacterial growth in a notable percentage of cases, suggesting a potential strategy to reduce contamination. However, persistent bacterial growth in some cases underscores the need for further research to optimize antiseptic measures during autologous cranioplasty. [ABSTRACT FROM AUTHOR]

Good mental preparation of an athlete plays an important role in achieving optimal sports results. An athlete who enters a competition should not feel fatigue resulting from intense physical exercise. Therefore, new and effective methods are being sought that could help accelerate the process of both physical and mental regeneration. Vibrotherapy is one of them. The aim of the study was to determine the optimal frequency of vibration, its duration and the position in which the subjects were placed during the treatments, in relation to the reduction of subjectively perceived exertion muscle pain, mental discomfort, emotional states and the level of cognitive processes that were disturbed by intense physical activity. Sixteen healthy male volunteers were involved in this study. The participants were assessed for their aerobic and anaerobic capacity. Each of the subjects performed a set of intensive physical exercises and then underwent vibrotherapy treatment. In random order, each of the men tested the effectiveness of eight combinations of frequency, duration, and body position. Psychological tests were conducted for each combination: frequency, duration of treatment, and position during treatment, in four stages: (1) before the start of the experiment (baseline POMS measurements), (2) immediately after the exercise (VAS scale, scale examining psychological discomfort and STROOP test), (3) immediately after the vibration treatment (POMS measurements, VAS scale, scale examining psychological discomfort and STROOP test), (4) 24 h after the vibration treatment (VAS scale examining subjective assessment of perceived pain and psychological discomfort). Based on the results, it was concluded that all the studied variables improved significantly over time (after the vibration treatment and 24 h after training). In addition, a statistically significant interaction measurement x frequency was noted for vigor scale (52HZ favored greater improvement in this state), and a statistically significant interaction was found for measurement x time for the VAS scale (p < 0.05) -- the lower pain value was indicated 24 h after the 10-min vibration treatment. The type of frequency used, position, and duration of the treatment did not play a statistically significant role in changing STROOP test results and severity of psychological discomfort (p > 0.05). [ABSTRACT FROM AUTHOR]

Background: Pediatric heart (HTx) and kidney transplant (KTx) recipients may have lower physical fitness than healthy children. This study sought to quantify fitness levels in transplant recipients, investigate associations to clinical factors and quality of life, and identify whether a quick, simple wall‐sit test is feasible as a surrogate for overall fitness for longitudinal assessment. Methods: Aerobic capacity (6‐min walk test, 6MWT), normalized muscle strength, muscle endurance, physical activity questionnaire (PAQ), and quality of life (PedsQL™) were prospectively assessed in transplanted children and matched healthy controls. Results: Twenty‐two HTx were compared to 20 controls and 6 KTx. 6MWT %predicted was shorter in HTx (87.2 [69.9–118.6] %) than controls (99.9 [80.4–120] %), but similar to KTx (90.3 [78.6–115] %). Muscle strength was lower in HTx deltoids (6.15 [4.35–11.3] kg/m2) and KTx quadriceps (9.27 [8.65–19.1] kg/m2) versus controls. Similarly, muscle endurance was lower in HTx push‐ups (28.6 [0–250] %predicted), KTx push‐ups (8.35 [0–150] %predicted), HTx curl‐ups (115 [0–450] %predicted), and KTx wall‐sit time (18.5 [10.0–54.0] s) than controls. In contrast to HTx with only 9%, all KTx were receiving steroid therapy. The wall‐sit test significantly correlated with other fitness parameters (normalized quadriceps strength R =.31, #push‐ups R =.39, and #curl‐ups R =.43) and PedsQL™ (R =.36). Conclusions: Compared to controls, pediatric HTx and KTx have similarly lower aerobic capacity, but different deficits in muscle strength, likely related to steroid therapy in KTx. The convenient wall‐sit test correlates with fitness and reported quality of life, and thus could be a useful easy routine for longitudinal assessment. [ABSTRACT FROM AUTHOR]

Background Mechanistic factors on the pathway to improving independent ambulatory ability among hip fracture patients by a multicomponent home-based physical therapy intervention that emphasized aerobic, strength, balance, and functional training are unknown. The aim of this study was to determine the effects of 2 different home-based physical therapy programs on muscle area and attenuation (reflects muscle density) of the lower extremities, bone mineral density (BMD), and aerobic capacity. Methods Randomized controlled trial of home-based 16 weeks of strength, endurance, balance, and function exercises (PUSH, n  = 19) compared to seated active range-of-motion exercises and transcutaneous electrical neurostimulation (PULSE, n  = 18) in community-dwelling adults >60 years of age within 26 weeks of hip fracture. Results In PUSH and PULSE groups combined, the fractured leg had lower muscle area and muscle attenuation and higher subcutaneous fat than the nonfractured leg (p  < .001) at baseline. At 16 weeks, mean muscle area of the fractured leg was higher in the PUSH than PULSE group (p  = .04). Changes in muscle area were not significantly different when compared to the comparative PULSE group. There was a clinically relevant difference in change in femoral neck BMD between groups (p  = .05) that showed an increase after PULSE and decrease after PUSH. There were generally no between-group differences in mean VO2peak tests at 16-week follow-up, except the PUSH group reached a higher max incline (p  = .04). Conclusions The treatment effects of a multicomponent home-based physical therapy intervention on muscle composition, BMD, and aerobic capacity were not significantly different than an active control intervention in older adults recovering from hip fracture. Trial Registration ClinicalTrials.gov Identifier: NCT01783704 [ABSTRACT FROM AUTHOR]

Aim: To determine the prevalence of adolescents who meet muscle‐strengthening activities (MSA) recommendation and their associations with anthropometric variables, physical fitness, and lifestyle behaviours in a sample of Spanish adolescents aged 12–17 years. Methods: This was a cross‐sectional study using data from The Eating Healthy and Daily Life Activities (EHDLA) Study. Participants reported the days on which they engaged in MSA (≥3 days per week were considered to meet World Health Organization recommendation). Physical fitness was assessed with the ALPHA fitness battery. Additionally, body mass index, waist circumference, skinfolds and body fat percentage were assessed. Lifestyle variables were recreational screen time, sleep time and adherence to the Mediterranean diet. The associations between MSA and outcome variables were tested with linear and logistic regressions. Results: Of the 852 participants, 48% met MSA recommendation. Meeting MSA recommendation was associated with lower adiposity and higher performance in the shuttle run test, maximal oxygen consumption, standing long jump, speed‐agility, flexibility, lower screen time (in weekdays) and higher adherence to the Mediterranean diet. Conclusion: Engaging in MSA once or twice a week was linked with more desirable health outcomes than not engaging in such activities. However, meet with MSA recommendation (i.e., at least 3 days per week) reinforced these benefits. [ABSTRACT FROM AUTHOR]

The physiological effects on blood flow and oxygen utilization in active muscles during and after involuntary contraction triggered by electrical muscle stimulation (EMS) remain unclear, particularly compared with those elicited by voluntary (VOL) contractions. Therefore, we used diffuse correlation and near-infrared spectroscopy (DCS-NIRS) to compare changes in local muscle blood flow and oxygen consumption during and after these two types of muscle contractions in humans. Overall, 24 healthy young adults participated in the study, and data were successfully obtained from 17 of them. Intermittent (2-s contraction, 2-s relaxation) isometric ankle dorsiflexion with a target tension of 20% of maximal VOL contraction was performed by EMS or VOL for 2 min, followed by a 6-min recovery period. DCS-NIRS probes were placed on the tibialis anterior muscle, and relative changes in local tissue blood flow index (rBFI), oxygen extraction fraction (rOEF), and metabolic rate of oxygen (rMRO2) were continuously derived. EMS induced more significant increases in rOEF and rMRO2 than VOL exercise but a comparable increase in rBFI. After EMS, rBFI and rMRO2 decreased more slowly than after VOL and remained significantly higher until the end of the recovery period. We concluded that EMS augments oxygen consumption in contracting muscles by enhancing oxygen extraction while increasing oxygen delivery at a rate similar to the VOL exercise. Under the conditions examined in this study, EMS demonstrated a more pronounced and/or prolonged enhancement in local muscle perfusion and aerobic metabolism compared with VOL exercise in healthy participants. NEW & NOTEWORTHY: This is the first study to visualize continuous changes in blood flow and oxygen utilization within contracted muscles during and after electrical muscle stimulation (EMS) using combined diffuse correlation and near-infrared spectroscopy. We found that initiating EMS increases blood flow at a rate comparable to that during voluntary (VOL) exercise but enhances oxygen extraction, resulting in higher oxygen consumption. Furthermore, EMS increased postexercise muscle perfusion and oxygen consumption compared with that after VOL exercise. [ABSTRACT FROM AUTHOR]

Purpose: Molecular hydrogen has been shown to possess antioxidant, antiinflammatory, ergogenic, and recovery-enhancing effects. This study aimed to assess the effect of molecular hydrogen administration on muscle performance, damage, and perception of soreness up to 24 h of recovery after two strenuous training sessions performed on the same day in elite fin swimmers. Methods: Eight females (mean ± SD; age 21.5 ± 5.0 years, maximal oxygen consumption 45.0 ± 2.5mL.kg-1.min-1) and four males (age 18.9 ± 1.3years, maximal oxygen consumption 52.2 ± 1.7mL.kg-1.min-1) performed 12 × 50m sprints in the morning session and a 400m competitive performance in the afternoon session. Participants consumed hydrogen-rich water (HRW) or placebo 3 days before the sessions (1,260mL/day) and 2,520mL on the experimental day. Muscle performance (countermovement jump), muscle damage (creatine kinase), and muscle soreness (100mm visual analogue scale) were measured during the experimental day and at 12 and 24 h after the afternoon session. Results: HRW compared to placebo reduced blood activity of creatine kinase (156 ± 63 vs. 190 ± 64 U.L-1, p = 0.043), muscle soreness perception (34 ± 12 vs. 42 ± 12 mm, p = 0.045), and improved countermovement jump height (30.7 ± 5.5 cm vs. 29.8 ± 5.8 cm, p = 0.014) at 12 h after the afternoon session. Conclusion: Four days of HRW supplementation is a promising hydration strategy for promoting muscle recovery after two strenuous training sessions performed on the same day in elite fin swimmers. [ABSTRACT FROM AUTHOR]

Objective: Anodal transcranial direct current stimulation (a-tDCS) has been used to improve athletic performance in various populations; however, its role in improving performance in elite athletes is unclear. This study aimed to investigate the effects of a-tDCS on athletic performance in elite athletes. Methods: We used a single-blind, randomized controlled experimental design and recruited 24 national-level freestyle swimmers from China. All athletes were randomly divided into two groups; the experimental group underwent a-tDCS (current 2 mA for 20 min) combined with physical training, and the control group underwent a-tDCS sham stimulation combined with physical training. The physical training program was identical in the experimental and control groups. The intervention period was 6 weeks, with five weekly sessions of 110 min each, consisting of 20 min of a-tDCS and 90 min of physical training. Base strength, explosive strength, aerobic endurance, and anaerobic endurance were measured in the athletes before and after the intervention. Results: The results were as follows. 1) Basic strength: There was a significant improvement in 5RM pull-ups in the experimental and control groups before and after the intervention (p < 0.05). 2) Explosive strength: There was a significant improvement in vertical jump and swimming start distance into the water in the experimental and control groups before and after the intervention (p < 0.05). 3) Aerobic endurance: There was no significant improvement in the experimental and control groups before and after the intervention. 4) Anaerobic endurance: There was a significant improvement in 400 m running performance in the experimental and control groups before and after the intervention (p < 0.05). Conclusion: Compared to physical training alone, a-tDCS combined with physical training can better improve the athletic performance of high-level swimmers, especially in basic strength, explosive strength, and aerobic endurance. [ABSTRACT FROM AUTHOR]

Evidence in the literature indicates that aerobic physical activity may have a protective role in aging pathologies. However, it has not been clarified whether different types of aerobic exercise produce different effects. In particular, these potential differences have not been explored in patients with Alzheimer's disease (AD). The present narrative review has the specific aim of evaluating whether land (walking/running) and water (swimming) aerobic activities exert different effects on cognitive functions and neural correlates in AD patients. In particular, the investigation is carried out by comparing the evidence provided from studies on AD animal models and on patients. On the whole, we ascertained that both human and animal studies documented beneficial effects of land and water aerobic exercise on cognition in AD. Also, the modulation of numerous biological processes is documented in association with structural modifications. Remarkably, we found that aerobic activity appears to improve cognition per se, independently from the specific kind of exercise performed. Aerobic exercise promotes brain functioning through the secretion of molecular factors from skeletal muscles and liver. These molecular factors stimulate neuroplasticity, reduce neuroinflammation, and inhibit neurodegenerative processes leading to amyloid-β accumulation. Additionally, aerobic exercise improves mitochondrial activity, reducing oxidative stress and enhancing ATP production. Aerobic activities protect against AD, but implementing exercise protocols for patients is challenging. We suggest that health policies and specialized institutions should direct increasing attention on aerobic activity as lifestyle modifiable factor for successful aging and age-related conditions. [ABSTRACT FROM AUTHOR]

Introduction: Rhythmic transcranial magnetic stimulation (rhTMS) has been shown to enhance auditory working memory manipulation, specifically by boosting theta oscillatory power in the dorsal auditory pathway during task performance. It remains unclear whether these enhancements (i) persist beyond the period of stimulation, (ii) if they can accelerate learning and (iii) if they would accumulate over several days of stimulation. In the present study, we investigated the lasting behavioral and electrophysiological effects of applying rhTMS over the left intraparietal sulcus (IPS) throughout the course of seven sessions of cognitive training on an auditory working memory task. Methods: A limited sample of 14 neurologically healthy participants took part in the training protocol with an auditory working memory task while being stimulated with either theta (5 Hz) rhTMS or sham TMS. Electroencephalography (EEG) was recorded before, throughout five training sessions and after the end of training to assess to effects of rhTMS on behavioral performance and on oscillatory entrainment of the dorsal auditory network. Results: We show that this combined approach enhances theta oscillatory activity within the fronto-parietal network and causes improvements in auditoryworking memory performance. We show that compared to individuals who received sham stimulation, cognitive training can be accelerated when combined with optimized rhTMS, and that task performance benefits can outlast the training period by ~ 3 days. Furthermore, we show that there is increased theta oscillatory power within the recruited dorsal auditory network during training, and that sustained EEG changes can be observed ~ 3 days following stimulation. Discussion: The present study, while underpowered for definitive statistical analyses, serves to improve our understanding of the causal dynamic interactions supporting auditory working memory. Our results constitute an important proof of concept for the potential translational impact of non-invasive brain stimulation protocols and provide preliminary data for developing optimized rhTMS and training protocols that could be implemented in clinical populations. [ABSTRACT FROM AUTHOR]

Poultry wastes are rich in organic matter, allowing their use as substrates for biogas production by anaerobic digestion (AD). The major difficulty in the anaerobic digestion of this protein-rich waste is ammonia inhibition. Different results of biochemical methane potential (BMP) were obtained after the mesophilic anaerobic digestion of different avian waste in batch mode. It was shown that using two different inoculum (Liger and Saint-Brieuc) sources and different substrate-to-inoculum (S/I) ratios does not have a significant effect on the biochemical methane potential of organic laying hen droppings (OLHD); an average of 0.272 Nm3 CH4·kg−1·VS was obtained with both inocula. Otherwise, it affects the hydrolysis constant KH, and it decreases when the substrate-to-inoculum ratio increases. Furthermore, Liger is the most suitable inoculum for our substrate because it shows stability during the process even with different organic loads. Comparing the biochemical methane potential of multiple avian wastes such as organic laying hen droppings and different slaughterhouse waste highlights the importance of slaughterhouse waste in the anaerobic digestion process because of the high methane yield observed especially with the viscera (0.779 Nm3 CH4·kg−1 VS, SD = 0.027 Nm3 CH4·kg−1 VS). Moreover, methane production was affected by increasing the ammonia concentrations; when [N-NH3] > 9.8 g·N-NH3·L−1, the biochemical methane potential decreases and the lag phase increases (λ > 30 days); a total inhibition of the process was observed when ammonia concentration is above 21.8 g·L−1. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the role of physical fitness on the FRAN CrossFit® workout time-trial. Twenty male athletes were divided into a fast group (FG) and a slow group (SG) according to the median value of the FRAN time-trial. Measurements included the FRAN time-trial, body composition analysis, isometric handgrip and isometric mid-thigh pull strength, countermovement jump (CMJ), 30 s continuous jumping test (CJ30), and one repetition maximum (1-RM) strength in the squat, thrusters, snatch, clean and jerk, and dead-lift. The FG had significantly lower body fat (p < 0.018), higher CMJ (p < 0.05), lower percentage decrement in CJ30 height (p = 0.023), and higher 1-RM strength (p < 0.05) compared to the SG. A significant correlation was found between the FRAN time-trial with percentage body fat (r = 0.512, p = 0.021) and with percentage decrement in CJ30 height (r = 0.454, p = 0.044). Performance in the FRAN time-trial was also correlated with CMJ variables (r ranged from 0.634 to 0.663, p < 0.05) and 1-RM strength (r ranged from 0.510 to 0.701, p < 0.05). These results suggest that the FG has a higher tolerance to fatigue and is stronger, more powerful, and has less body fat compared to the SG. Consequently, body fat, 1-RM strength, power, and anaerobic capacity may predict the FRAN time-trial in CrossFit® athletes. [ABSTRACT FROM AUTHOR]

Anaerobic capacity is an important determinant of swimming performance, and a feasible land-based test for measuring swim-specific anaerobic capacity is lacking. This study assessed the test-retest reliability of a swim-specific modification of the Wingate anaerobic capacity test: the WAnT-Swim. Ten competitive and fitness swimmers from the local college community completed four WAnT-Swim tests, two per day on two separate days, to determine peak, mean, and low power, as well as fatigue index (FI). Reliability was assessed using coefficients of variation (CV), intraclass correlation coefficients (ICC), and Pearson correlations. Power output exhibited low CV (<6%) with excellent reliability (ICC ≥0.98) and strong associations between tests (r ≥.92). FI demonstrated the weakest reliability (CV = 3.9 ± 1.0%; ICC = 0.65; r =.13). These data suggest that the WAnT-Swim, when administered using the VASA swimming ergometer, is a reliable test of anaerobic power during land-based swimming. [ABSTRACT FROM AUTHOR]

Due to the character of the taekwondo, the adenosine triphosphate–phosphocreatine system provides the energy for each kick, the glycolytic system supports the repeated execution of kicks, and the aerobic system promotes recovery between these movements and the bout. Therefore, taekwondo athletes require high explosive power and anaerobic capacity in order to carry out sustained and powerful attacks. So, the purpose of this study is to compare the effects of APRE and VBRT on lower-limb explosive power and anaerobic capacity in college taekwondo players. A total of 30 taekwondo players completed an 8-week training intervention with autoregulatory progressive resistance exercise (APRE; n = 15) and velocity-based resistance training (VBRT; n = 15). Testing included the one-repetition maximum squat, countermovement jump (CMJ), taekwondo anaerobic intermittent kick test (TAIKT), and 30-s Wingate anaerobic test (WAnT). (1) Intragroup comparisons revealed significant effects for one-repetition maximum squat, peak power of CMJ (CMJ PP), relative peak power of CMJ (CMJ RPP), and total number of TAIKT (TAIKT TN) in both the APRE and VBRT groups. The VBRT group exhibited small effect sizes for time at peak power of WAnT (WAnT PPT) and moderate effect sizes for peak power of WAnT (WAnT PP), relative peak power of WAnT (WAnT RPP), and fatigue index of TAIKT (TAIKT FI), whereas the APRE group exhibited small effect sizes for TAIKT FI. (2) Intergroup comparisons revealed no significant effects in any of the results. However, VBRT demonstrated a moderate advantage in WAnT PP and WAnT RPP , whereas APRE had a small advantage in CMJ PP and CMJ RPP. These findings suggest that APRE improved explosive power (CMJ PP and CMJ RPP) more, whereas VBRT improved anaerobic power output (WAnT PP and WAnT RPP) more. Both methods were found to have similar effects in improving the anaerobic endurance (WAnT PPT and TAIKT TN) and fatigue index (power drop of WAnT and TAIKT FI). [ABSTRACT FROM AUTHOR]

Background: It is internationally known that our population is aging. At the same time, some patients with COVID-19, due to their symptoms, required mechanical ventilation (MV) and subsequent pulmonary rehabilitation (PR). This study aimed to compare the effects of a multimodal PR program "ADULT" versus "OLDER" people with COVID-19 who were on MV. Methods: The intervention consisted of an 8-week hybrid PR program (2x week). Forced vital capacity (FVC) was measured at the beginning and end of PR, upper and lower limb strength was obtained through hand grip strength (HGS) and the sit-to-stand test (STST), respectively, and functional exercise capacity was measured with the 6-minute walking test (6MWT). Results: The main results were an increase in the FVC in the ADULT and OLDER groups (time effect, P = 0.000; η2 = 0.27), an increase in HGS in the ADULT and OLDER groups (time effect, P = 0.000; η2 = 0.52), in the same way, the number of repetitions on the STST increased in the ADULT and OLDER groups (time effect, P = 0.000; η2 = 0.55). Finally, the distance covered on the 6MWT increased in the ADULT and OLDER groups (time effect, P = 0.000; η2 = 0.65). Conclusions: The PR program is an effective strategy to improve FVC, muscle strength, and functional exercise capacity similarly in adults and older people with post severe COVID-19 who required MV. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to compare the effects of two concurrent training (CT) protocols on the physical fitness of middle school students. Method: A 12-week quasi-experimental pre-test/post-test study was conducted with 157 middle school students (age = 12.48 ± 0.34, n = 90 females) divided into three groups: CT group A (CT-0h) received combined resistance training (RT) and aerobic training (AT) in each physical education session, CT group B (CT-48h) received RT and AT across two separate physical education classes 48 h apart, and a control group (Con) received no training. Training occurred twice a week. Test indicators included cardiorespiratory fitness (CRF) measured by estimated VO2max and 20 m shuttle run (laps), as well as muscle strength assessed through long jump, vertical jump, and handgrip strength. Results: The intervention groups exhibited significant increases in estimated VO2max and muscle strength compared to their baseline values (p < 0.05). Both CT- 0h and CT-48h groups demonstrated significant improvements in 20 m shuttle run (laps) (mean difference: 8.88 laps, p < 0.01; mean difference: 4.81 laps, p < 0.01, respectively), standing long jump (mean difference: 6.20 cm, p < 0.01; mean difference: 3.68 cm, p < 0.01, respectively), vertical jump (mean difference: 4.95 cm, p < 0.01; mean difference: 4.04 cm, p < 0.01, respectively), and handgrip strength (mean difference: 11.17 kg, p < 0.01; mean difference: 6.99 kg, p < 0.01, respectively). CT-0h group exhibited significantly increased estimated VO2max (mean difference: 1.47 ml/kg/min, p < 0.01) compared to the CT-48h group. Conclusion: Both CT programs effectively improved adolescents' physical fitness indicators. However, the program that integrated RT and AT within the same physical education class demonstrated superior enhancement in adolescents' CRF. [ABSTRACT FROM AUTHOR]

Background: We sought to create a system to evaluate the physical fitness of outstanding Chinese male boxers that included an evaluation index, fitness level criteria, and modeling. This system was then used to assess athletes' physical fitness and development. Methods: Documentation, expert interviews, questionnaires, measurements, and statistical analyses were used in this study. Results: The physical fitness evaluation system included the following three components: (1) body shape indexes (n = 4) including the backhand upper arm circumference differential, finger span height, Cottrell index, and pelvic width/ shoulder width x 100; (2) body function indexes (n = 4) including relative maximum anaerobic power, relative maximal oxygen uptake, and creatine kinase and testosterone concentrations; and (3) athletic quality indexes (n = 9) including the speed strength index, the backhand straight punch strength, 3-min cumulative punching force, backhand straight punch reaction time, backhand straight punch speed, 30-m sprint, 9-min double shake jump rope, 1-min double shake jump rope, and sitting forward bend tests. A five-point grading system to evaluate physical fitness was established and an evaluation model was proposed. Conclusions: The reference values were determined to be objective and effective using a back substitution process. Individual and differential assessments reflected the athletes; level of physical fitness. The critical values were established under the best and worst conditions and the optimal values were found to be valid and effective. [ABSTRACT FROM AUTHOR]

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Breath-hold diving is explained as an activity that requires enduring muscle asphyxia and acidosis, high anaerobic capacity, and the tactic of the dive. Therefore, this study aimed to construct and validate tests that will mimic anaerobic processes in the specific media of freedivers. The sample of participants included 34 Croatian freedivers (average age: 26.85 ± 4.0 years, competitive age: 3.82 ± 1.92 years, their body height: 180.14 ± 8.93 cm, and their body mass: 76.82 ± 12.41 kg). The sample of variables consists of anthropometric indices, competitive efficiency (maximal length of a dive (DYN)), and specific anaerobic capacities (100 m and 2 min tests). Newly developed tests included the swimming anaerobic sprint test (SAST) and diving anaerobic sprint test (DAST). DAST and SAST variables included the total time of the test (DAST/SAST) and the fastest interval (DASTmax/SASTmax). The results showed good reliability of the tests with high Cronbach alpha coefficients (DAST: 0.98, DASTmax: 0.97, SAST: 0.99, SASTmax: 0.91). Furthermore, pragmatic validity shows a high correlation among all variables and DAST (DYN: −0.70, 100 m: 0.66, 2 min: −0.68). High relation is also found between 100 m (0.96), 2 min (−0.94), and a moderate result for DYN (−0.43) and the SAST test. A factor analysis extracted one significant factor. The factor analysis involved DAST, SAST, DYN, 100 m, and 2 min tests regarding factor 1. After the examination of all variables, the total time of the DAST test showed the best predictive values for the performance of divers. However, both tests could be used for diagnostics and the evaluation of specific condition abilities in freediving. [ABSTRACT FROM AUTHOR]