Muscular Endurance Performance Research Articles

Maintained cognitive gains after 10 weeks of cognitively engaging exercise via reducing body fat in overweight children

ABSTRACT This study aimed to determine whether the exercise-induced cognitive benefits persist after the interventions end and whether the persistence of cognitive gains following the intervention depends on the post-intervention exercise behaviour. Overweight children aged 10–12 years were enrolled in a 16-week afterschool program. During the first 10 weeks, children were randomised to receive the cognitively engaging movement games (CEMG) (N = 27) or the sedentary control (N = 27) interventions. During the subsequent 6-week post-intervention period, children self-selected either CEMG or sedentary activities daily. Perceptual discrimination performance, fitness, and body fat were measured before, immediately after, and 6-week after the intervention. Immediately after the intervention, the CEMG group improved aerobic capacity, muscular endurance, muscle power, body fat, and perceptual discrimination performance compared with the control group, and most of these benefits persisted after 6 weeks following the cessation of intervention. During the 6-week post-intervention period where CEMG and sedentary activities were both available, the CEMG group chose to engage in CEMG more frequently and with higher intensity on those days than the control group. The post-intervention exercise behaviours were positively related to the persistence of cognitive gains, and these associations were mediated through decreased body fat. Collectively, the 10-week CEMG intervention has positive effects not only on physical and cognitive outcomes, but also post-intervention self-selected exercise behaviours that may help maintain intervention-induced cognitive gains in overweight children. Future research controlling for factors impacting children’s behavioural choice and determining the differential effects of CEMG versus traditional exercise regimen is needed. Trial registration: Thai Clinical Trials Registry identifier: TCTR20220913006.

Effects of 8days intake of hydrogen-rich water on muscular endurance performance and fatigue recovery during resistance training.

Exercise-induced oxidative stress and inflammation can impair muscular function in humans. The antioxidant and anti-inflammatory properties of molecular hydrogen (H2) highlight its potential to be as an effective nutritional supplement to support muscular function performance in healthy adults. However, the effects of H2 supplementation on muscular endurance performance in trained individuals have not been well characterized. This study aimed to assess the effects of intermittent hydrogen-rich water (HRW) supplementation before, during, and after resistance training on muscular endurance performance, neuromuscular status, and subjective perceptual responses after a 48-h recovery period. This randomized, double-blinded, placebo-controlled cross-over study included 18 trained men aged 19.7 ± 0.9years. Participants in this study were instructed to consume 1,920mL of HRW or pure water (Placebo) daily for 7days. Additionally, participants were required to supplement with HRW or pure water five times during the training day (1,260mL total). This included drinking 210mL 30min and 1min before training, 210mL between training sets, 210mL immediately after training, and 420mL 30min into the recovery period. Participants performed half-squat exercises with the load set at 70% of one repetition maximum for six sets (half-squat exercise performed to repetitions failure each set). We measured the power output and number of repetitions in the free barbell half-squat used to assess muscular endurance performance in participants. The countermovement jump (CMJ) height, total quality recovery scale (TQRS), and muscle soreness visual analog scale (VAS) scores were measured to assess fatigue recovery status after training, as well as at 24 and 48h of recovery. The total power output (HRW: 50,866.7 ± 6,359.9W, Placebo: 46,431.0 ± 9,376.5W, p = 0.032) and the total number of repetitions (HRW:78.2 ± 9.5 repetitions, Placebo: 70.3 ± 9.5 repetitions, p = 0.019) in the H2 supplemented group were significantly higher than in the placebo group. However, there was no statistically significant difference (p< 0.05) between the H2 and placebo groups in CMJ, TQRS, and VAS. Eight days of intermittent HRW intake could significantly improve muscular endurance performance in trained individuals, making it a promising strategy for athletes or fitness enthusiasts looking to boost muscular endurance during resistance training or competitions. However, it should be noted that HRW intake alone may not be adequate to accelerate recovery from muscle soreness or fatigue following high-intensity training.

The effect of low-intensity suspension training with blood flow restriction on GH, IGF-1, and their association with physical fitness in young women.

Blood flow restriction (BFR) has been incorporated in resistance training for over 20 years. We aimed to investigate the impact of low-intensity suspension training with BFR (LIST+BFR) on GH, IGF-1, and their association with physical fitness in young women. Thirty-six active women participated and were randomly assigned to either the high-intensity suspension training (HIST), LIST+BFR, or control (CON) groups. Training groups exercised three sessions weekly for 8 weeks. The CON only engaged in regular physical activity. Fasting serum hormones and physical fitness were assessed 48 h before and after the training intervention. GH and IGF-1 levels significantly higher in the LIST+BFR compared to the HIST and CON. These hormones were significantly higher by HIST, compared to CON. LIST+BFR led to significant enhancements in muscular strength and endurance compared to HIST and CON. Additionally, HIST significantly higher than compared to CON. Sprinting and agility time lower in both suspension training groups rather than the CON. No significant between-groups differences were found in weight. There was a large or moderate correlation between GH and IGF-1 and muscular strength, endurance, sprint, and agility performance. LIST+BFR could more enhanced GH, IGF-1, and muscular strength and endurance in females than HIST.

Sex Differences in the Ergogenic Response of Acute Caffeine Intake on Muscular Strength, Power and Endurance Performance in Resistance-Trained Individuals: A Randomized Controlled Trial.

This study assessed the impact of acute caffeine intake on muscular strength, power, and endurance performance between resistance-trained male and female individuals according to load in upper- and lower-body exercises. Here, 76 resistance-trained individuals (38 females, 38 males) participated in a study comparing caffeine and a placebo. Each received either 3 mg/kg of caffeine or a placebo 60 min before tests measuring muscular strength and power through bench press and back squat exercises at different intensities (25%, 50%, 75%, 90% 1RM). Muscular endurance at 65% 1RM was also assessed by performing reps until reaching task failure. Compared to placebo, caffeine increased mean, peak and time to reach peak velocity and power output (p < 0.01, ηp2 = 0.242-0.293) in the muscular strength/power test in males and females. This effect was particularly observed in the back squat exercise at 50%, 75% and 90% 1RM (2.5-8.5%, p < 0.05, g = 1.0-2.4). For muscular endurance, caffeine increased the number of repetitions, mean velocity and power output (p < 0.001, ηp2 = 0.177-0.255) in both sexes and exercises (3.0-8.9%, p < 0.05, g = 0.15-0.33). Acute caffeine intake resulted in a similar ergogenic effect on muscular strength, power, and endurance performance in upper- and lower-body exercises for male and female resistance-trained participants.

Effects of 8 Weeks Conditioning Exercises on Muscular Endurance: A Cross-Sectional Study of Female Cadets of Ghana Immigration Service Academy, Assin Fosu, Ghana

Physical conditioning enables athletes to meet all the physical requirements of their sport, perform well, and minimize their risk of injury. This study aims to determine the effects of eight (8) weeks conditioning training on the muscular endurance of Female Cadets of the Ghana Immigration Service Academy. The Army Physical Training Fitness Test (APFT) was used to evaluate muscular endurance levels of the Female Cadets. The quasi-experimental pre-test post-test study design was used to conduct the study. A total of 60 female cadets were randomly stratified into two groups based on APFT age categories (22-26) and (27-31) years. Data was analyzed using descriptive statistics and paired sample t-test and independent sample t-test was used to test the hypothesis. Higher upper body muscular endurance performance as measured by the APFT was observed in the age group (27-31) years compared to age group (22-26) years. Significant difference was found in muscular endurance in the females age groups (22-26) and (27-31) years (P&amp;lt;0.05). Significant positive effect on muscular endurance after conditioning exercises for female Cadets in both age categories, (22-26) and (27-31) years (P&amp;lt;0.05) was observed. Conditioning exercises had a significant impact on APFT upper body muscular endurance performance in the age categories of (22-26) and (27-31) years.

Nose vs. mouth breathing– acute effect of different breathing regimens on muscular endurance

BackgroundIt has been reported that the way we breathe (whether through the nose or mouth) can influence many aspects of our health and to some extent, sport performance. The purpose of this study was to evaluate the acute effects of different breathing regimens on muscular endurance and physiological variables.MethodsA randomized experiment to verify the acute effect of different breathing regimens (NN– inhaling and exhaling through the nose; NM– inhaling through the nose, exhaling through the mouth; MM– inhaling and exhaling through the mouth) on the muscular endurance performance was conducted. 107 physically active college students (68 males, 39 females) performed repeated bench press testing protocol (repetitions to failure (RTF) with 60% of body weight for males (BP60), respectively 40% of body weight for females (BP40)) with various breathing regimens (NN, NM, MM) in random order. Heart rate (HR), blood oxygen saturation (SpO2) and perceived exertion by Borg scale (RPE) were measured as well. A short questionnaire, given after the testing protocol and observation during familiarization, was used to detect each subject’s normal breathing approach during resistance training.ResultsIn both genders, no significant differences in RTF, RPE and SpO2 were found. No individual case of deviation of arterial oxygen saturation outside the physiological norm was recorded. ​​In the male group, significantly lower HR values were found during the NN trials, compared to during the NM (p = 0.033) and MM (p = 0.047) trials with no significant differences in females. The HR differences in the males demonstrated a small effect size (NN < NM, d = 0.32; NN < MM, d = 0.30). Questionnaire results suggest that 80% of our participants use NM breathing, 15% use MM breathing and 5% use NN breathing during resistance training.ConclusionIt seems, that various breathing regimens have none or only minor effect on muscular endurance performance and selected physiological parameters. NN seems to be as efficient as other two regimens, which are mostly used in practice (NM, MM).

Effect of resistance training programs differing in set structure on muscular hypertrophy and performance in untrained young men.

Purpose: This study aimed to compare the effects on muscle hypertrophy and muscular performance of two resistance training (RT) programs that differed only in set structure: traditional set structure (TS) vs. rest redistribution set structure (RR). Methods: Thirty untrained young men were pair-matched and randomly assigned to a TS (n = 15) or an RR (n = 15) protocol based on individual baseline measures. Participants trained for 8weeks using the same total body RT routines performed twice weekly. The TS protocol comprised four sets of 10 repetitions per exercise with 120-s interset rest, and the RR involved eight sets of five repetitions per exercise with 51-s interset rest. Participants were tested pre- and post-intervention for body composition, regional muscle thickness, upper- and lower-body muscle maximal strength [1-repetition maximum (1RM)], mean power output and velocity at 75% 1RM and muscular endurance (repetitions to failure at 70% 1RM). Results: Compared to baseline, both groups exhibited equally significantly decreased body fat mass (p < 0.05), increased fat-free mass (p < 0.001), muscle thickness (p < 0.05), upper and lower-body muscular maximal strength (p < 0.001) and endurance performance (p < 0.001). However, both groups only increase the lower-body power output (p < 0.001) but not the upper-body (p > 0.05). No significant differences existed between groups for all measurements (p > 0.05). Conclusion: These results suggest that RR and TS groups have similar effects for improving muscle hypertrophy and performance in untrained young men.

Effect of Movement Tempo During Resistance Training on Hypertrophy and Muscular Fitness: A Narrative Literature Review

Although many studies have demonstrated whether movement tempo, a training variable during resistance exercise, has an effect on muscle performance, there are still gray areas related to muscle hypertrophy and muscular fitness in different populations. The aim of this narrative systematic review was to investigate the effect of movement tempo on muscular performance such as maximal strength, skeletal muscle hypertrophy, muscle power and muscular endurance in resistance training performed at specific frequencies. Three electronic databases were searched using terms related to movement tempo and resistance training. The included studies were those published in English using randomized and non-randomized comparative dynamic resistance exercise interventions in healthy adults. The results suggest that changing the tempo of movement during resistance training may have an effect on muscle hypertrophy, but the results are not conclusive. There are conflicting research results, although faster tempos seem to be advantageous in terms of power outcomes at different movement tempos. More studies are needed to evaluate muscular endurance performance in terms of movement tempo. Differences in the size of the muscles studied, the structure of the training programs, and the standardization of the experimental approach and data collection tools used may partially explain the inconsistency in the results between tempos in different contraction phases or in the same contraction phases.

Effects of mental fatigue and attentional focus on muscular endurance performance

ABSTRACT Mental fatigue shows consistent detrimental effects on physically-demanding tasks including running and muscular endurance tasks. Several strategies to mitigate these effects have been assessed; however, it is also important to explore factors that may combine with mental fatigue to amplify performance decrements. The present study investigated potential moderating effects of attentional focus on the mental fatigue – endurance performance relationship. Undergraduates (N = 78) completed two wall-sit tasks to volitional failure prior to, and following, a cognitive task. Using a 2 X 2 randomised factorial design, half the participants completed a mentally fatiguing cognitive task (incongruent Stroop; HF), while the other half performed a non-mentally fatiguing task (documentary viewing; LF). Prior to the second wall-sit task, half the participants in each of the HF and LF groups were given attentional focus instructions to focus internally (INT) and the other half to focus externally (EXT). Both the mental fatigue (p < .001) and attentional focus (p < .001) manipulations were found to be successful. Planned comparisons showed no significant effects of attentional focus or mental fatigue on wall-sit endurance performance. However, a large effect size was observed between the HF/INT group and the other three groups (d = −1.56). Overall, data indicate a potential moderating effect of attentional focus such that internal focus and high mental fatigue may combine to have detrimental effects on physical endurance performance.

Effects of resistance training on muscular strength, endurance, body composition and functional performance among sarcopenic patients: a systematic review.

Sarcopenia, a gradual loss of muscle mass and strength associated with ageing, contributes to a decline in physical abilities, increase in disability and frailty and loss of functional independence. This functional deterioration which comes with ageing, can be slowed in pace with exercise. The objective of the current review was to thoroughly search for literature assessing impact of RT on physical performance, body composition, muscle strength and endurance in sarcopenic elderly patients. PubMed, Scopus, Web of Science, and PEDro databases were brought in use for a thorough search for articles published from 2010 to 2023. Two researchers independently retrieved data from studies that complied with the inclusion and exclusion criteria, while they also evaluated quality of the evidence. In total, 14 studies with 742 patients with mean age of 72.4 ± 9.22 years were included in the analysis for this review. Results indicate, RT improves body composition (p = 0.001), functional performance (p 0.001), postural stability (p = 0.005) and muscle strength (p 0.001) in elderly sarcopenic patients. A promising intervention for the management of sarcopenia is RT. To yield RT's positive effects, a well-designed prescription is the need of the hour, just like it is with other treatment strategies.

Associations between Smoking Status and Health-Related Physical Fitness and Balance Ability among Older Males in Taiwan.

The primary aim of this study was to examine the relationships between smoking status and health-related physical fitness and balance ability in older males residing in Taiwan. This investigation adopted a cross-sectional design, utilizing data from 7688 older males who took part in the 2014-2015 wave of the National Physical Fitness Survey of Taiwan. Various data sources, including a standardized structured questionnaire, anthropometric measurements, health-related physical fitness assessments, and balance ability tests, were analyzed. The participants were divided into three categories based on their smoking habits: never smokers, former smokers, and current smokers. Multiple regression analyses were performed to evaluate the linear association between cigarette smoking status and health-related physical fitness and balance ability performance. Health-related physical fitness and balance performance were significantly greater (p < 0.05) in the never smoker group than in the current smoker group. Current smoking status was significantly negatively (p < 0.05) associated with cardiopulmonary function, muscular endurance, flexibility, and balance performance. A history of smoking (former smoker) was significantly negatively (p < 0.05) associated with the 2-min step test, 30-s arm curl and chair stand, as well as the 8-foot up-and-go test; however, the association was not significant for the back scratch, chair sit-and-reach, and one-leg stance with eyes open performance. These results suggest that current cigarette smoking is detrimental to health-related physical fitness and balance performance in older males. Quitting smoking may reverse the effects of smoking on overall body flexibility and static balance performance in Taiwanese older adults, thereby reducing the risk of falls and incapacity.

Comparison of The Effect of Static and Dynamic Core Exercises on Physical Performance Parameters in Young Boxers

The purpose of the study was to investigate the effects of 6 weeks of static and dynamic core exercises on physical performance parameters in young boxers. Twenty well-trained young male boxers aged 14-18 years old were voluntarily involved in the study. All participants were grouped randomly into dynamic and static core exercise groups. A six-week core exercise training program was performed on static and dynamic core exercise groups. Anthropometric measurements and physical performance tests; Yo-yo intermittent recovery test level 1, 30m speed test, hexagon agility test, standing long jump, maximum push-up, 30s sit-ups, flamingo balance and sit and reach flexibility tests were performed repeated 2 times before and after 6 weeks of training. Data were collected before and after six weeks of core exercise training and were analyzed using Paired t-test and ANCOVA test procedures. The results indicated that the core exercise training program significantly improved both groups' speed, agility, long jump, muscular endurance and 30m sprint performance. (p

Load and muscle group size influence the ergogenic effect of acute caffeine intake in muscular strength, power and endurance.

Although acute caffeine intake seems to improve muscular strength-power-endurance performance, there is scarce evidence evaluating upper vs lower-body exercises at different loads. Thus, this study aimed to examine the effects of acute caffeine intake on upper and lower-body muscular strength, power and endurance performance at different loads. Twenty resistance-trained athletes (male/female: 10/10; age: 23 ± 4years; body mass: 70.6 ± 15.1) participated in a double-blind, placebo-controlled, cross-over and randomized study. Participants were provided with either 3mg/kg of body mass of caffeine or maltodextrin (placebo). Sixty minutes after ingestion, they performed muscular strength and power assessment for bench press and back squat exercise at 25%, 50%, 75% and 90% 1-repetition-maximum (1RM), performing 3, 2, 1 and 1 repetitions respectively, followed by muscular endurance assessment for both exercises at 65% and 85% 1RM performing until task failure. Isometric handgrip, isometric mid-thigh pull and vertical jump tests were also performed. In muscular strength and power, compared to placebo, caffeine improved mean velocity (P = 0.045; pη2 = 0.101), mean power (P = 0.049; pη2 = 0.189) and rate of force development (RFD, P = 0.032; pη2 = 0.216), particularly in back squat exercise at 75% and 90% 1RM where mean velocity increased by 5-7% (P = 0.48-0.038; g = 0.348-1.413), mean power by 6-8% (P = 0.050-0.032; g = 0.547-0.818) and RFD by 17-97% (P = 0.042-0.046; g = 1.436-1.196). No differences were found in bench press exercise. In muscular endurance, caffeine improved the number of repetitions in all exercises and loads (P = 0.003; pη2 = 0.206), but only in back squat exercise at 85% 1RM, caffeine increased mean and peak velocity (8-9%, P = 0.006-0.004; g = 2.029-2.075), mean and peak power (10-13%, P = 0.006-0.003; g = 0.888-1.151) and force peak (3%, P = 0.009; g = 0.247). Acute caffeine intake (3mg/kg) improved muscular strength, power and endurance performance, revealing a more pronounced effect at high-loads (≥ 75% 1RM) and in lower-body (back squat) than in upper-body exercise (bench press) according to muscle group size.

Functional and Traditional Resistance Training Are Equally Effective in Increasing Upper and Lower Limb Muscular Endurance and Performance Variables in Untrained Young Men

Background: Functional resistance training (FRT) has been proposed as a safe alternative to traditional resistance training (TRT) for developing neuromuscular adaptation capacity and improving muscular strength and competitive performance. This study sought to compare the effects of 6 weeks of FRT and TRT on upper and lower limb muscular endurance and performance variables in untrained young men. Methods: Twenty-nine untrained healthy young males aged 18–29 years were randomly given 6 weeks of FRT [40% of 1repetition maximum (RM), 4,5 sets of 20 repetitions, 3 times/week] or TRT (70% of 1RM, 4,5 sets of 12 repetitions, 3 times/week). All participants underwent numerous tests before and after the 6-week training, such as muscular endurance (reps of bench press and leg flexion) and physical performance tests (sprint performance, pull-ups, throwing ability, and jumping ability). Results: After the 6 weeks of training, the TRT and FRT groups showed an equally significant increase in muscular endurance (p < 0.01), while the throwing and jumping abilities, 30-m sprint, and pull-ups performances in both the groups (p < 0.01) also improved significantly. However, no differences were observed between the groups (p > 0.05). Conclusion: These findings indicate that both functional resistance training and traditional resistance training are effective training methods for improving the upper and lower limb muscular endurance and performance in untrained young men.

Effects of Creatine Nitrate and Caffeine Alone and Co‐ingested on Anaerobic and Muscular Endurance Performance

BACKGROUNDIngestion of creatine nitrate and caffeine individually improve anaerobic and muscular endurance performance; however, co‐ingestion of creatine nitrate and caffeine remains unclear.METHODSIn a double‐blind, randomized, placebo‐controlled cross over study, 12 resistance‐trained participants (22±1 y; 180.0±9.5 cm; 85.9±15.1 kg) completed 4 conditions in random order: creatine nitrate (CN: 5 g/day + 0.675 g/day of maltodextrin), caffeine (CAF: 400 mg/day + 5 g/day of maltodextrin), CN+CAF (5 g/day of creatine nitrate + 400 mg/day of caffeine), and placebo (PL: 5.4 g/day of maltodextrin). Supplements were ingested for 7 days with a 7‐day washout period between conditions. Before and after supplementation, muscular endurance (bench press and leg press; 3 sets at 70% 1RM) and a Wingate anaerobic test were performed. Peak power (PP), mean power (MP), and fatigue index (FI) were calculated. Data were analyzed using a two‐way (within‐within) analysis of variance (p≤0.05) with a Tukey’s post hoc when appropriate. Absolute change (post minus pre‐testing) was calculated and analyzed with a repeated‐measures ANOVA.RESULTSThere was a significant main effect of time for both leg press (p=0.009) and bench press (p&lt;0.001) with post‐testing greater than pre‐testing; however, there were no differences between conditions. For peak power, there was no significant interaction (p=0.436), the main effect of time (p=0.967), or differences between conditions for absolute change (p=0.436). For mean power, there was a significant interaction (p=0.037); however, post hoc analysis revealed no significant pairwise effects; however, absolute change for mean power between conditions was significant (p=0.037), with post hoc analysis revealing a trend (p&lt;0.10) for both CN conditions (CN alone and CN+CAF) to be superior compared to CAF. There were no significant differences between conditions or overtime for fatigue index.CONCLUSIONShort‐term CN and CAF ingested either individually, or co‐ingested could not augment upper or lower body muscular endurance or anaerobic performance compared to PL in resistance‐trained participants.

Halo Sport Transcranial Direct Current Stimulation Improved Muscular Endurance Performance and Neuromuscular Efficiency During an Isometric Submaximal Fatiguing Elbow Flexion Task.

The present study examined the effects of transcranial direct current stimulation (tDCS) using Halo Sport on the time to exhaustion (TTE) in relation with muscle activities and corticomuscular coupling of agonist and antagonist muscles during a sustained isometric fatiguing contraction performed with the elbow flexors. Twenty healthy male college students were randomly assigned to tDCS group and control group. The two group participants performed two experimental sessions which consisted of pre-fatigue isometric maximal voluntary contraction (MVC), sustained submaximal voluntary contractions (30% maximal torque) performed to exhaustion, and post-fatigue MVC with the right elbow flexor muscles. Sham stimulation (90 s) and tDCS (20 min) were applied for control and tDCS group participants 20 min prior to the second session test, respectively. MVC strength in pre- and post-fatigue test, TTE, electroencephalogram (EEG), and electromyography (EMG) of biceps brachii (BB) and triceps brachii (TB) were recorded during the tests. It was found that tDCS using the Halo Sport device significantly increased TTE and thus improved muscular endurance performance. The improvement may be partly related to the improvement of neuromuscular efficiency as reflected by decrease of antagonistic muscle coactivation activities, which may be related to cortical originated central processing mechanism of neuromuscular activities.

The Acute Effects of Normobaric Hypoxia on Strength, Muscular Endurance and Cognitive Function: Influence of Dose and Sex.

Simple SummaryHypoxic training is a novel method to increase resistance training adaptations. There is some evidence that resistance exercise performed in systemic hypoxia can lead to structural and functional adaptations of skeletal muscle. Studies have also demonstrated that normobaric hypoxia (i.e., normal pressure, low oxygen) increases intramuscular metabolic stress and type two (fast twitch) fiber recruitment, which leads to a greater morphological adaptations over time. However, to date, there is no research that has investigated the effects of different doses of acute normobaric hypoxia on strength and muscular endurance performance, nor has there been research investigating potential sex-based differences.The aim of this study was to examine the acute effects of different levels of hypoxia on maximal strength, muscular endurance, and cognitive function in males and females. In total, 13 males (mean ± SD: age, 23.6 ± 2.8 years; height, 176.6 ± 3.9 cm; body mass, 76.6 ± 2.1 kg) and 13 females (mean ± SD: age, 22.8 ± 1.4 years; height, 166.4 ± 1.9 cm; body mass, 61.6 ± 3.4 kg) volunteered for a randomized, double-blind, crossover study. Participants completed a one repetition strength and muscular endurance test (60% of one repetition maximum to failure) for squat and bench press following four conditions; (i) normoxia (900 m altitude; FiO2: 21%); (ii) low dose hypoxia (2000 m altitude; FiO2: 16%); (iii) moderate dose hypoxia (3000 m altitude; FiO2: 14%); and (iv) high dose hypoxia (4000 m altitude; FiO2: 12%). Heart rate, blood lactate, rating of perceived exertion, and cognitive function was also determined during each condition. The one repetition maximum squat (p = 0.33) and bench press (p = 0.68) did not differ between conditions or sexes. Furthermore, squat endurance did not differ between conditions (p = 0.34). There was a significant decrease in bench press endurance following moderate (p = 0.02; p = 0.04) and high (p = 0.01; p = 0.01) doses of hypoxia in both males and females compared to normoxia and low dose hypoxia, respectively. Cognitive function, ratings of perceived exertion, and lactate were also significantly different in high and moderate dose hypoxia conditions compared to normoxia (p < 0.05). Heart rate was not different between the conditions (p = 0.30). In conclusion, high and moderate doses of acute normobaric hypoxia decrease upper body muscular endurance and cognitive performance regardless of sex; however, lower body muscular endurance and maximal strength are not altered.

Acute effect of betaine supplementation on muscular endurance during resistance exercise in trained men: a pilot and randomized study

Objective: To analyse the acute effect of betaine supplementation on muscular endurance in weight training practitioners. Design: An experimental, crossover, randomized and double-blind study. Methods: The sample composed of 10 male subjects practicing resistance training (age: 23.71 ± 4.23 years old). Participants performed 2 sessions (i.e., Betaine x Placebo) with 3 sets of repetitions until failure with 70% of 1RM. The participants were provided 3 minutes of recovery between sets and 48 hours between sessions. The 24H food recall was evaluated before each exercise session. Results: There were no significant differences in carbohydrates (p = 0.732), protein (p = 0.684), fat (p = 0.271), or in total energy consumption (p = 0.865). A time effect occurred for the training session (F (2,18) = 54.626, p < 0.0001, η2 = 0.859), with a linear reduction in the number of repetitions performed throughout the series for both conditions (1set > 2set > 3set). However, there was no interaction (F (2,18) = 0.625, p= 0.546, η2 = 0.065) or condition effect (F(1,9) = 0.045, p = 0.837, η2 = 0.005). Conclusion: Acute betaine supplementation had no effect on muscular endurance performance in the bench press.

Dissociative or associative cognitions: a focus on muscle pain can be more effective for muscular endurance performance

ABSTRACT The perception of painful bodily sensations is usually negatively associated with endurance performance, and dissociative strategies are routinely recommended to divert attention away from these signals. The effectiveness of dissociative strategies has not been clearly established, but associative strategies seem to benefit physically trained individuals. The purpose of this study was to clarify and compare the effects of these two strategies on the maintenance of physical effort in a physically active population. We hypothesised that an associative focus would increase endurance performance more than a dissociative focus. The participants (572: 161 women and 411 men) performed muscular endurance tasks until exhaustion in associative and dissociative conditions. The aerobic fitness level could be tested in 285 participants using a maximum aerobic speed field test. To perform additional statistical analyses, two fitness-level groups were created based on the median. Our results showed that participants performed better in the associative condition than the dissociative condition, and complementary analyses revealed that association specifically improved performance in the higher aerobic fitness group. These results suggest that monitoring afferent painful signals could be an interesting attentional strategy and that individuals can develop abilities to tolerate and apprehend this sensory feedback. These results are discussed in relation to a recent interoceptive model of physical effort.

High Dose of Caffeine Mouth Rinse Increases Resistance Training Performance in Men.

Caffeine mouth rinsing (CMR) has been shown to enhance exercise performance. However, no studies have analyzed the effects of different dosages of CMR on muscular performance. Therefore, the purpose of this study was to examine the effects of different dosages of CMR on strength (bench press 1 repetition maximum (1-RM)) and muscular endurance (60% of 1-RM repetitions to failure) in resistance-trained males. Fourteen resistance-trained males (age: 23 ± 2 years, height: 179 ± 3 cm, body mass: 83 ± 4 kg, BMI: 17 ± 2 kg/m2) completed four conditions in random order. The four conditions consisted of a mouth rinse with 25 mL solutions containing either 1% (250 mg) of CMR (low dose of CMR: LCMR), 2% (500 mg) of CMR (moderate dose of CMR: MCMR), 3% (750 mg) of CMR (high dose of CMR: HCMR) and sweetened water (placebo: PLA) for 5 s prior to a bench press strength and muscular endurance test. Maximal strength, muscular endurance, heart rate (HR) and ratings of perceived exertion (RPE) were recorded for each condition. There were no significant differences in strength (p = 0.30) and HR (p = 0.83) between conditions. HCMR significantly increased muscular endurance performance (p = 0.01) and decreased RPE values (p = 0.01). In conclusion, CMR did not affect bench press 1-RM strength performance, but muscular endurance responses to CMR seems to be dose-dependent.