Sprint Exercise Research Articles

Evaluating bioenergetic pathway contributions from single to multiple sprints

This study aims to investigate the changes in bioenergetic pathway contributions during repeated sprint exercises with an increasing number of repetitions. Twelve male amateur soccer players executed a single 20 m sprint and three repeated-sprint protocols (5 × 20 m, 10 × 20 m, 15 × 20 m with 15-second rest intervals), analyzing oxidative, glycolytic, and ATP-PCr energy pathways using the PCr-LA-O2 method. Findings revealed a significant decline in energy expenditure and performance outputs as the number of sprint repetitions increased. While the oxidative and ATP-PCr pathways’ energy contributions significantly rose with more sprints, the glycolytic pathway’s contribution notably increased only up to the 10 × 20 m protocol, then stabilized. Although the ATP-PCr pathway’s energy contribution decreased slightly from sprints 1–5 to 11–15, it remained significantly higher than the oxidative and glycolytic pathways throughout. Initially, glycolytic contribution surpassed oxidative in sprints 1–5, equaled it in sprints 6–10, and fell below in sprints 11–15. Glycolytic activity, a major energy source initially (about 36%), diminished substantially with more sprints (below 7% in the 15th sprint). This indicates that the decrease in non-mitochondrial pathway energy, particularly glycolytic, outstrips the aerobic system’s increased tolerance. These findings offer physiological insights into the relationship between performance decrement and bioenergetic metabolism in repeated sprints.

Effects of Preconditioning Lower-Extremity Resistance Exercises on Multidirectional Repeated Sprinting-Induced Muscle Damage.

Hsu, SM, Tseng, WC, Chiu, CH, Hsieh, TY, Weng, MC, Dai, X, and Chen, CH. Effects of preconditioning lower-extremity resistance exercises on multi directional repeated sprinting-induced muscle damage. J Strength Cond Res XX(X): 000-000, 2024-Sprint exercise-induced muscle damage is a popular area of investigation. To examine whether preconditioning lower-extremity resistance exercises would reduce the amount of muscle damage observed after a multi-directional repeated sprinting (MDS) exercise. Thirty-six elite male athletes were randomly allocated to 1 of 3 groups: general warm-up (GW), GW with loaded jump squat (SQ), and GW with loaded hip thrust (HT). Knee flexion isometric strength (MVIC), passive hip flexion range of motion (ROM), soreness, countermovement jump (CMJ), sprint time, and plasma creatine kinase (CK) activity were measured at the pretest and post-24, -48, and -72 hours of the MDS. For SQ, the CK at post-72 hours was significantly lower than the GW group. The decrements of MVIC at post-48 and -72 hours for SQ were significantly less than the GW group. The CMJs at post-24 and -48 hours for SQ and at post-48 and -72 hours for HT were significantly higher than the GW group. The 0-10 m sprint time at post-48 hour for HT was significantly better than the GW group. Adding the SQ or HT interventions to a GW before MDS has a protective effect on the sprinting-induced muscle damage and faster recovery.

Impact of virtual reality immersion on exercise performance and perceptions in young, middle-aged and older adults.

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

Repeated Sprint Variations According to Circadian Rhythm at Different Menstrual Cycle Phases.

This study assessed the repeated sprint performance in relation to circadian rhythm during different menstrual cycle phases (MCP). Twelve volunteer eumenorrheic women team sport athletes performed 5×6-s cycling sprints in morning (9 am to 10 am) and evening (6 pm to 7 pm) sessions during the mid-follicular (FP, 6th-10th d) and luteal phases (LP, 19th-24th d). Body weight, oral body temperature, resting heart rate and lactate levels together with estradiol, progesterone and cortisol levels were determined before tests. Relative peak and mean power and performance decrements were determined as performance variables and maximum heart rate, lactate and ratings of perceived exertion were determined as physiological variables. Evening body temperatures were significantly higher. Cortisol levels were higher in the morning and in the FP. Resting lactate levels did not vary with MCP or time of day, but a significant MCP x time of day interaction was observed. Body weight showed no change according to time of day and MCP. There was no significant effect of MCP and time of day on performance and physiological variables, in contrast, maximum lactate values were notably higher in the evening. In conclusion, MCP and time of day need not be considered during repeated sprint exercises of eumenorrheic women athletes.

Effects of Dietary Nitrate Supplementation on High-Intensity Cycling Sprint Performance in Recreationally Active Adults: A Systematic Review and Meta-Analysis.

This systematic review and meta-analysis investigated the influence of dietary nitrate supplementation on performance metrics during cycling sprint exercise according to the PRISMA guidelines. Searches were conducted on MEDLINE, PubMed, ScienceDirect, Scopus, and SPORTDiscus databases up to September 2023. Inclusion criteria were healthy recreationally active men and women who consumed nitrate-rich and nitrate-deficient beetroot juice to assess performance outcomes of mean power, peak power, time-to-peak power, and minimum power during 30-s cycling sprints. Risk of bias was assessed using the Cochrane Risk of Bias 2 and TESTEX tools and funnel plots. A random effects model was performed on six studies and showed that dietary nitrate had significant effects on time-to-peak power (SMD: -0.66, 95% CI: -1.127 to -0.192, p = 0.006) but not on mean power, peak power, or minimum power. Subgroup analysis revealed that an acute low nitrate dose improved time-to-peak power (SMD: -0.977, 95% CI: -1.524 to -0.430, p < 0.001) but not after a multiday moderate nitrate dose (SMD: -0.177, 95% CI: -0.619 to -0.264, p = 0.431). These data suggest that acute nitrate supplementation can benefit time-to-peak power during 30-s cycling sprints, but due to the limited availability of data and heterogeneity in methodology, these results should be interpreted with caution. There was insufficient data on women to analyze sex-based differences. Future studies are required to provide insight on how supplementation regimen and population impact the effects of dietary nitrate for enhancing cycling sprint performance.

Sex Differences in the Energy System Contribution during Sprint Exercise in Speed-Power and Endurance Athletes.

Background/Objectives: A high level of specific metabolic capacity is essential for maximal sprinting in both male and female athletes. Various factors dictate sex differences in maximal power production and energy utilization. This study aims to compare the contribution of energy systems between male and female athletes with similar sport-specific physiological adaptations during a 15-s sprint exercise. Methods: The endurance group consisted of 17 males (23 ± 7 y) and 17 females (20 ± 2 y). The speed-power group included 14 males (21.1 ± 2.6 y) and 14 females (20 ± 3 y). The contribution of phosphagen, glycolytic, and aerobic systems was determined using the three-component PCr-LA-O2 method. Results: Significant differences were observed in the energy expenditure for all systems and total energy expenditure between males and females in both groups (p = 0.001-0.013). The energy expenditure in kJ for individual systems (phosphagen-glycolytic-aerobic) was 35:25:7 vs. 20:16:5 in endurance males vs. female athletes, respectively. In the speed-power group, male athletes expended 33:37:6 kJ and female athletes expended 21:25:4 kJ, respectively. The percentage proportions did not differ between males and females in any system. The contribution of the phosphagen-glycolytic-aerobic systems was 52:37:11 vs. 48:39:13 in endurance male and female athletes, respectively. For speed-power males vs. female athletes, the proportions were 42:50:8 vs. 41:50:9, respectively. Conclusions: Despite the differences in body composition, mechanical output, and absolute energy expenditure, the energy system contribution appears to have a similar metabolic effect between male and female athletes engaged in sprint exercises with similar sport-related adaptations. The magnitude and profile of sex differences are related to sports discipline.

Neuromuscular response of young athletes during plyometric and sprint exercises

The objective was to analyse the neuromuscular response during jumping and sprint exercises in young athletes and adults. Young athletes were divided into 2 groups: indoor soccer (SOC, n = 12) and rugby (RUG, n = 12) and adults were physical education students (PE, n = 12). Sport groups were trained systematically for their sport for 5 years and performed resistance training at least for 2 years. Neuromuscular response was evaluated using a vertical jump test (CMJA), 15-meter sprint test (SPRI) and a rebound test at 3HZ (REB). Force and electromyography were measured during all tests. Leg stiffness (Kvert), rate of force development (RFD) and muscle activation were calculated and analysed. Pre activation and contact EMG were measured for all tests. EMG signal was normalized by CMJA. There were no differences in maturation level between young sport groups as shown by Mirwald’s formula (p = .897). Significant differences were found in favour of RUG vs SOC during CMJA (p = .029). For SPRI and REB, there were no statistical differences between groups for RFD (p = .585) and (p = .056). Kvert showed no group differences among CMJA (p = .396), SPRI (p = .329) and REB (p = .429). It is concluded that a systematic training in young athletes allows the accelerated development of neuromuscular performance.

Can Neuromuscular Electrical Stimulation Enhance the Effect of Sprint Interval Training?

The aim of this study was to determine the effects of subtetanic neuromuscular electrical stimulation combined with voluntary exercise between repeated Wingate tests on sprint exercise performance and blood lactate accumulation during sprint interval training. Fifteen healthy young males volunteered. After 1-min baseline, participants underwent the Wingate test twice. They performed a 4-min intervention between tests: neuromuscular electrical stimulation with free-weight cycling or voluntary cycling alone [43.6 (8.0) watts], which matched oxygen consumption with neuromuscular electrical stimulation with free-weight cycling. The blood lactate concentration was assessed at the end of the baseline, at 3-min intervention, and on recovery at 1, 3, 5, and 10 min after the second Wingate test. Peak and mean blood lactate concentration during recovery were significantly greater with neuromuscular electrical stimulation with free-weight cycling than voluntary cycling alone (P>0.036 and P=0.011, respectively). Peak power, mean power, and rate of decline (fatigue index) were not significantly different between conditions in both Wingate tests (condition/interaction all P>0.300, partial η2<0.1). Subtetanic neuromuscular electrical stimulation combined with voluntary exercise indicated similar exercise performance and fatigue levels during Wingate tests, but enhanced blood lactate accumulation compared to oxygen consumption-matched voluntary cycling during sprint interval training.

Cycle-based high-intensity sprint exercise elicits acute cognitive dysfunction in psychomotor and memory task performance

PurposeTo examine the impact of an acute high-intensity sprint exercise protocol (HISEP) for eliciting post-exercise cognitive dysfunction in psychomotor, attentional, executive, and memory tasks.MethodsTwenty-four recreationally active adults (22 ± 4 yrs, 169.39 ± 10.07 cm, 75.80 ± 14.73 kg, 27.03 ± 9.55 BF%) performed a HISEP on a cycle ergometer. Average psychomotor reaction time (avgRT; Dynavision D2 Mode A &amp;amp; Mode B), mood (Profile of Mood States Questionnaire; POMS), and cognition (Automated Neuropsychological Assessment Metrics; ANAM) were assessed pre- (PRE), post- (POST) and 60-min post (60POST) HISEP. One-way repeated measures ANOVAs were used to assess changes across time.ResultsFatigue (main effect: p &amp;lt; 0.001, ηp2 = 0.309) was significantly higher at POST compared to PRE (p = 0.007). Tension (main effect: p = 0.021, ηp2 = 0.154) was significantly lower at 60POST compared to PRE (p = 0.029). Mode A avgRT (main effect: p = 0.022, ηp2 = 0.153) was significantly slower at POST compared to PRE (p = 0.026). Throughput (TP) scores for ANAM code substitution-delayed (CSD) task (main effect: p &amp;lt; 0.001, ηp2 = 0.284) and matching to sample (M2S) tasks (main effect: p = 0.014, ηp2 = 0.169) were significantly lower at POST compared to PRE (p = 0.001 and p = 0.025, respectively), while mathematical processing (main effect: p = 0.002, ηp2 = 0.232) was significantly higher at 60POST compared to both PRE (p = 0.019) and POST (p = 0.005). No other significant changes in cognitive task performance were observed (p's &amp;gt; 0.05).ConclusionsThe HISEP is a feasible and time-effective fatiguing exercise stimulus capable of eliciting acute cognitive dysfunction in psychomotor and memory task performance. NCT05100589.

Effects of Short-term Repeated Sprint Exercise Training and Moderate Intensity Continuous Exercise Training on Vascular Function in Healthy Young Adults

Effects of Short-term Repeated Sprint Exercise Training and Moderate Intensity Continuous Exercise Training on Vascular Function in Healthy Young Adults

Impact of Time of Day on Glycemia in Response to Postprandial Supramaximal Sprints in Adults With Type 1 Diabetes

ObjectivesIn this study we explore the impact of postprandial exercise timing (morning vs evening) on glycemia in individuals with type 1 diabetes (T1D) during short all-out sprints on a cycle ergometer. MethodsTen healthy physically sedentary male (n=7) and female (n=3) volunteers with type 1 diabetes, 22.8±2.8 years of age, and with a diabetes duration of 9.7±5.5 years and glycated hemoglobin level of 8.6±1.2%, underwent comprehensive screening and assessment of their physical health and fitness status before study participation, under the guidance of a physician. Each participant underwent 2 postprandial exercise sessions on separate days: the first in the morning at 8:00 AM and second in the evening at 8:00 PM, both conducted 60 minutes after a standardized meal. ResultsMorning exercise showed a less pronounced reduction in plasma glucose (PG) levels compared with evening exercise (−2.01±1.24 vs −3.56±1.6 mmol/L, p=0.03). In addition, higher cortisol levels were observed in the morning vs evening (128.59±34 vs 67.79±26 ng/mL, p<0.001). ConclusionsMorning repeated sprint exercise conducted in the postprandial state consistent with the protective effect of higher cortisol levels resulted in a smaller reduction in PG levels compared with evening exercise. This highlights the potential influence of exercise timing on glycemic responses and cortisol secretion in the management of T1D.

Effects of high-intensity sprint exercise on neuromuscular function in sprinters: the countermovement jump as a fatigue assessment tool.

High-intensity sprint exercises (HIS) are central to sprinter training and require careful monitoring of athlete muscle fatigue to improve performance and prevent injury. While the countermovement jump (CMJ) may be used to monitor neuromuscular fatigue (NMF), little is known about the specific effects from HIS. The purpose of this study is to investigate the effects of HIS on the CMJ to assess its utility for assessing NMF following HIS. Ten male collegiate 400 m sprinters completed a 400 m sprint fatigue protocol and underwent five CMJ-testing sessions (baseline, 3 minutes, 10 minutes, 1 hour and 24 hours) over two days. Three CMJ trials, performed on a force plate, were completed each trial, with rating of perceived exertion (RPE) recorded as a subjective fatigue measure. Changes in RPE, CMJ variables, force-time and power-time curves at baseline and post fatigue were assessed. Significant changes were observed in most variables following the fatigue protocol. In particular, concentric mean power remained significantly lower after 24 hours compared to baseline. In addition, the force-time curves exhibited a significant reduction in all conditions following the fatigue protocol. This decline was most pronounced within 50-75%of the concentric phase relative to baseline measurements. Conclusion. Results indicate that the CMJ may be a useful tool for monitoring fatigue in at least 400 m sprinters. These data also indicate that HIS may disproportionately reduce force output in during concentric movement. These insights may improve training prescriptions and injury prevention strategies for sprint athletes.

Title: Influence of the NASA SPRINT exercise protocol on myonuclear and satellite cell content of the vastus lateralis and soleus during 70 days of bedrest

Objectives: The purpose of this study was to assess the effcacy of the NASA SPRINT exercise protocol in preserving myonuclear and satellite cell number of the quadriceps (vastus lateralis) and triceps surae (soleus) muscles following 70 days of bedrest (i.e., simulated microgravity). These two muscles were the focus of this study because they both atrophy significantly with microgravity exposure in the absence of countermeasures. Hypotheses: The SPRINT exercise protocol will preserve myonuclear number (MNN), myonuclear domain (MND), and satellite cell number (SCN) during 70 days of bedrest. Methods: Subjects were randomized into three groups: bedrest only (BR; n=8, 37±3 y), bedrest with endurance and resistance exercise (BRE; n=9, 34±2 y) and bedrest with endurance and resistance exercise and low dose testosterone injections (BRE+T; n=8, 33±3 y). Muscle biopsies were taken before and at the end of bedrest from the vastus lateralis and soleus, and were sectioned, immunofluorescently stained, and analyzed for MNN (myonuclei/fiber), MND (μm2/myonuclei), and SCN (satellite cells/fiber) in slow (myosin heavy chain (MHC) I) and fast (MHC IIa) muscle fibers. SCN was only determined in MHC I fibers for the soleus. Results: MNN, MND, and SCN in MHC I and IIa fibers of the vastus lateralis and soleus were unchanged (p&lt;0.05) from pre- to post-bedrest within BR, BRE, and BRE+T. However, there was a main effect for time (p&lt;0.05) for a decrease in MND for vastus lateralis MHC I fibers (-8%), as well as soleus MHC I (-18%) and IIa (-18%) fibers. Also, there was a trend for a main effect for time (P=0.059) for an increase (+37%) in SCN for vastus lateralis MHC IIa fibers, which was driven primarily by the exercise groups (BR: -4%, BRE: +36%, BRE+T: +67%). Conclusions: Myonuclear number appears to be unaltered during 70 days of simulated microgravity with or without countermeasures exercise. As a result, any changes in myonuclear domain correspond with alterations in muscle mass. Satellite cell number also appears to be relatively refractory to change, but may be influenced in fast muscle fibers under the combined dynamic cellular control mechanisms of exercise and atrophy encountered during relatively long-duration simulated microgravity. Funding Source: This research was supported by the National Aeronautics and Space Administration, NNJ06HF59G; the Institute for Translational Sciences at the University of Texas Medical Branch, supported in part by a Clinical and Translational Science Award (UR1TR000071) from the National Center for Advancing Translational Sciences, National Institutes of Health; the NASA Flight Analogs Project; and the Human Bioenergetic Program at Ball State University. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

How does rest Interval duration affect performance? An experiment on high-intensity sprint exercises

Introduction: The purpose of this study was to examine the effects of interval and high-intensity sprint training (RST) with different rest intervals on the respiratory function, aerobic and anaerobic power. (2) Materials and Methods: The study involved the voluntary participation of 20 male participants. The participants were divided into two groups: 2IRG (2-minute rest between repeated sprints) and 4IRG (4-minute rest between repeated sprints). The changes in the respiratory function, aerobic, and anaerobic power parameters were examined in the 2IRG and 4IRG athletes who performed two training sessions per week for 4 weeks. (3) Results: The findings indicated that there was no improvement in the respiratory function among the athletes, but there was a significant improvement in aerobic and anaerobic power parameters. However, this improvement was similar in both the 2IRG and 4IRG groups. (4) Conclusions: A 4-week high-intensity interval training program with two RST sessions per week was insufficient to elicit improvements in the respiratory function. However, RST protocols with 2-minute and 4-minute rest intervals provided similar aerobic and anaerobic benefits.

Effects of Repeated High-Intensity Effort Training or Repeated Sprint Training on Repeated High-Intensity Effort Ability and In-Game Performance in Professional Rugby Union Players.

Glaise, P, Rogowski, I, and Martin, C. Effects of repeated high-intensity effort training or repeated sprint training on repeated high-intensity effort ability and in-game performance in professional rugby union players. J Strength Cond Res 38(5): 932-940, 2024-This study investigated the effects of repeated high-intensity efforts (RHIE) training compared with repeated sprint exercise (RSE) training on RHIE ability (RHIEa) and in-game performance in professional rugby union players. Thirty-nine, male, professional, rugby union players were randomly assigned to 3 training groups (RHIE training, RSE training, and control). Repeated high-intensity effort ability and high-intensity effort characteristics (including sprints, acceleration, and contact efforts) during official games were measured before and after a 10-week specific (RHIE, RSE, or control) training period. The results of this study showed that concerning RHIEa, both the RHIE and RSE training significantly increased the players' average sprint velocity ( p < 0.001, d = -0.39 and p < 0.001, d = -0.53 respectively), average sled push velocity (ASPV; p < 0.001, d = -0.81 and p = 0.017, d = -0.48 respectively), and RHIE score ( p < 0.001, d = -0.72 and p < 0.001, d = -0.60 respectively). Repeated high-intensity effort training trended in a smaller increase in average sprint velocity than RSE training, a larger increase in ASPV, and a similar increase in RHIE score. Concerning in-game high-intensity efforts, both the RHIE and RSE training produced significant improvements in the number of sprints ( p = 0.047, d = -0.28 and p < 0.001, d = -0.47 respectively), total distance ( p < 0.001, d = -0.50 and p = 0.002, d = -0.38 respectively), the number of accelerations ( p < 0.001, d = -0.37 and p = 0.003, d = -0.32 respectively), and contact rate ( p < 0.001, d = -0.97 and p = 0.020, d = -0.28 respectively). Conversely, the magnitude of the increase in contact rate was almost twice as high in RHIE compared with RSE training. To conclude, the findings of this study were that both RSE and RHIE training are effective methods for developing RHIEa and in-game high-intensity efforts in professional rugby union. In practical applications, as the gains in certain abilities and game performance data differed depending on the training method chosen, we suggest that coaches choose the most appropriate method according to the profile of the players, their position, and the style of play they want to develop.

Effects of Nordic versus Sprint Exercise Program in Prevention of Hamstring Injuries in Football Players

Background: Hamstring strain injuries (HSI) are frequent in football and other high-speed running sports. Nordic hamstring exercise (NHE) has been found to increase eccentric hamstring strength and decrease the risk of hamstring strain injury (HSI). Sprint exercise, which includes maximal eccentric contractions, is supposed to engage the hamstrings and prevent HSI. Objective: The aim of this randomized controlled trial was to compare the effectiveness of Nordic and sprint exercise programs in preventing hamstring injuries in football players. Methods: The study involved 26 male football players aged 18-25 years, who exercised regularly for 2-3 times a week in the preceding 3 months. They were randomly divided into two groups. One group received Nordic exercise and conventional treatment, while the other group received sprint training exercises and conventional treatment. The duration of the program was 6 weeks, with two 30-minute sessions per week. The evaluation was based on the 40m sprint test and active knee extension test, which were measured using a goniometer. The 40m sprint was timed, and the active knee extension test measured the range of motion. The results were analyzed based on these measurements. Results: The participants' average ages, heights, and weights were respectively 21.1538 1.91191, 1.74 0.029, and 74.8462 4.18275. Shapiro-Wilk test was applied showed data to be non-parametric distributed (P &lt; 0.05). Wilcoxon and Mann Whitney tests were used to analyze the difference between pre- and post-treatment scores in the experimental and control groups. which were found to significanlty improved in experimental group, while both groups found to be improved significantly in a pre-post analysis, p value &lt; 0.05. Conclusion: Both Nordic and sprint exercise programs were effective in reducing the risk of hamstring injuries. However, the Nordic exercise program showed significantly greater improvement in preventing HSI in football players.

The influence of acute sprint exercise on cognition, gaming performance, and cortical hemodynamics in esports players and age-matched controls

The relationship between esports and cognitive performance has recently gained increasing interest in the scientific community. However, our knowledge of the effects of acute sprint exercise (SE) on game performance and cognitive performance of esports players (as compared to age-matched controls) is scant. To address this gap, this study using a between-subjects design with pretest-posttest comparisons recruited amateur esports players aged between 18 and 35 years, and healthy age-matched controls who did not play esports games. The participants performed the Go/No-go test, Tracking Test, and the First Person Shooter (FPS) game Valorant immediately before and 5 and 30 min after SE. In addition to the behavioral performance, changes in the cortical hemodynamics of the prefrontal cortex (PFC) were recorded before and after the acute physical exercise while playing Valorant using functional near-infrared spectroscopy. The results show that amateur esports players have superior performance in both game performance (p < .001) and specific measures of cognitive performance (i.e., Tracking Test, p < .05), regardless of the sessions. After the acute physical exercise, the gaming performance in both groups improved, and amateur esports players showed a higher accuracy in the Go/No-go task 30 min after SE. Regarding PFC cortical hemodynamics, no significant difference was noticed in the oxygenation values of both groups between pre and post tests, and between-group differences (p > .05). In conclusion, our study provides evidence that (i) amateur esports players have superior cognitive performance in specific domains and (ii) an acute bout of physical exercise can increase the gaming performance of both amateur esports players and healthy age-matched controls.

Influence of Relative Age on Physical Condition and Academic Performance in Adolescents.

Annual age grouping is a common organizational strategy in academics and sports. This strategy could promote the relative effects of age, which refers to the (dis)advantages that subjects who were born in the first or last months of the year may suffer. The consequences could be minimized, resulting in better physical and/or academic results. The objective of the study was to evaluate the influence of the quarter of birth and examine the correlation between physical condition variables and academic performance. The sample included 79 students (51.90% females) 13.46 ± 0.21 years old in the second year of Obligatory Secondary Education. The physical variables of this study were explosive power, cardiorespiratory capacity, speed, flexibility, and muscle strength. They were evaluated using the horizontal jump tests, Cooper test, 50 m sprint, sit-and-reach test, and medicine ball exercises, respectively. The academic variables were obtained from the average academic grade, grouped by key competencies. An Analysis of Covariance (ANCOVA), controlling for gender, body mass, and height, revealed significant differences between male students born in the first quarter compared to those born in subsequent quarters in all physical condition variables (except for cardiorespiratory capacity). For female students, significant differences were observed only in the explosive power variable. No statistically significant intra-sex differences were evident in academic performance at any time of measurement. Additionally, moderate to large correlations were found in the physical condition and academic variables. It is concluded in relation to the need to implement diverse strategies regarding the process of developing physical conditions in adolescence that satisfy the growth needs of students based on age and sex.

Effects of Ramadan intermittent fasting on performance, physiological responses, and bioenergetic pathway contributions during repeated sprint exercise.

This investigation aims to elucidate the impact of Ramadan intermittent fasting on performance, physiological responses, and bioenergetic pathway contributions during repeated sprints. Fourteen active male Muslim athletes (age = 22.4 ± 1.8 years, body weight = 69.5 ± 3.8 kg, height = 176 ± 5.1 cm) executed a repeated sprint protocol, consisting of ten 20-meter sprints with 15-s passive recovery intervals, during both fasting and non-fasting conditions. The fasting session was conducted after a 12-14 h fast following Sahur (the pre-dawn meal during Ramadan). In contrast, the non-fasting session occurred before the Ramadan fasting period began, during the same hours of the day, at a time when fasting was not yet required for the athletes. Bioenergetic pathway contributions during repeated sprints were quantified using the PCr-LA-O2 method. The mean sprint time during fasting sessions was 3.4 ± 0.3 s compared to 3.3 ± 0.2 s in non-fasting sessions, indicating a trend approaching the threshold of significance for slower times in the fasted state (p = 0.052, effect size (ES) = 0.34). In terms of bioenergetic contributions, the total metabolic energy expenditure (TEE) was slightly lower during fasting sessions (236.5 ± 22 kJ) compared to non-fasting sessions (245.2 ± 21.7 kJ), but this difference was not statistically significant (p = 0.102, ES = 0.40). Similarly, metabolic energy expenditure per sprint was 23.7 ± 2.2 kJ in fasting conditions compared to 24.5 ± 2.2 kJ in non-fasting conditions (p = 0.106, ES = 0.35). The oxidative energy contribution did not differ significantly between fasting (34.2 ± 4.1 kJ) and non-fasting conditions (34.2 ± 4.1 vs. 35.5 ± 5.2 kJ; p = 0.238, ES = 0.28). Similarly, lactic (60.4 ± 7.6 vs. 59.2 ± 8.3 kJ; p = 0.484, ES = 0.15); and alactic (149.3 ± 19.9 vs. 143 ± 21.5 kJ; p = 0.137, ES = 0.30) energy contributions showed no significant differences between the fasting and non-fasting sessions. The percentage of performance decrement (Pdec) and the percentage contributions of oxidative, lactic, and alactic pathways to the total energy expenditure did not differ significantly between the fasting and non-fasting conditions, indicating a similar bioenergetic profile across both conditions. The present findings indicate no significant differences in performance metrics and metabolic outcomes between fasted and non-fasted states. Future assessments with longer duration and higher intensity protocols may provide further insights.

NASA SPRINT exercise program efficacy for vastus lateralis and soleus skeletal muscle health during 70 days of simulated microgravity.

The efficacy of the NASA SPRINT exercise countermeasures program for quadriceps (vastus lateralis) and triceps surae (soleus) skeletal muscle health was investigated during 70 days of simulated microgravity. Individuals completed 6° head-down-tilt bedrest (BR, n = 9), bedrest with resistance and aerobic exercise (BRE, n = 9), or bedrest with resistance and aerobic exercise and low-dose testosterone (BRE + T, n = 8). All groups were periodically tested for muscle (n = 9 times) and aerobic (n = 4 times) power during bedrest. In BR, surprisingly, the typical bedrest-induced decrements in vastus lateralis myofiber size and power were either blunted (myosin heavy chain, MHC I) or eliminated (MHC IIa), along with no change (P > 0.05) in %MHC distribution and blunted quadriceps atrophy. In BRE, MHC I (vastus lateralis and soleus) and IIa (vastus lateralis) contractile performance was maintained (P > 0.05) or increased (P < 0.05). Vastus lateralis hybrid fiber percentage was reduced (P < 0.05) and energy metabolism enzymes and capillarization were generally maintained (P > 0.05), while not all of these positive responses were observed in the soleus. Exercise offsets 100% of quadriceps and approximately two-thirds of soleus whole muscle mass loss. Testosterone (BRE + T) did not provide any benefit over exercise alone for either muscle and for some myocellular parameters appeared detrimental. In summary, the periodic testing likely provided a partial exercise countermeasure for the quadriceps in the bedrest group, which is a novel finding given the extremely low exercise dose. The SPRINT exercise program appears to be viable for the quadriceps; however, refinement is needed to completely protect triceps surae myocellular and whole muscle health for astronauts on long-duration spaceflights.NEW & NOTEWORTHY This study provides unique exercise countermeasures development information for astronauts on long-duration spaceflights. The NASA SPRINT program was protective for quadriceps myocellular and whole muscle health, whereas the triceps surae (soleus) was only partially protected as has been shown with other programs. The bedrest control group data may provide beneficial information for overall exercise dose and targeting fast-twitch muscle fibers. Other unique approaches for the triceps surae are needed to supplement existing exercise programs.