Ergogenic Effect Research Articles

Warm-Up Intensity Does Not Affect the Ergogenic Effect of Sodium Bicarbonate in Adult Men.

This study determined the influence of a high- (HI) versus low-intensity (LI) cycling warm-up on blood acid-base responses and exercise capacity following ingestion of sodium bicarbonate (SB; 0.3g/kg body mass) or a placebo (PLA; maltodextrin) 3hr prior to warm-up. Twelve men (21 ± 2years, 79.2 ± 3.6kg body mass, and maximum power output [Wmax] 318 ± 36W) completed a familiarization and four double-blind trials in a counterbalanced order: HI warm-up with SB, HI warm-up with PLA, LI warm-up with SB, and LI warm-up with PLA. LI warm-up was 15min at 60% Wmax, while the HI warm-up (typical of elites) featured LI followed by 2 × 30s (3-min break) at Wmax, finishing 30min prior to a cycling capacity test at 110% Wmax. Blood bicarbonate and lactate were measured throughout. SB supplementation increased blood bicarbonate (+6.4 mmol/L; 95% confidence interval, CI [5.7, 7.1]) prior to greater reductions with HI warm-up (-3.8 mmol/L; 95% CI [-5.8, -1.8]). However, during the 30-min recovery, blood bicarbonate rebounded and increased in all conditions, with concentrations ∼5.3mmol/L greater with SB supplementation (p < .001). Blood bicarbonate significantly declined during the cycling capacity test at 110%Wmax with greater reductions following SB supplementation (-2.4mmol/L; 95% CI [-3.8, -0.90]). Aligned with these results, SB supplementation increased total work done during the cycling capacity test at 110% Wmax (+8.5kJ; 95% CI [3.6, 13.4], ∼19% increase) with no significant main effect of warm-up intensity (+0.0kJ; 95% CI [-5.0, 5.0]). Collectively, the results demonstrate that SB supplementation can improve HI cycling capacity irrespective of prior warm-up intensity, likely due to blood alkalosis.

Polyphenol consumption and endurance exercise performance: A systematic review and meta-analysis of randomised controlled trials

Introduction: Consumption of polyphenols is proposed to reduce oxidative damage and increase nitric oxide synthesis and availability, thereby inducing physiological effects that enhance endurance exercise performance. Thus, the objective of this study was to systematically review the literature to evaluate the effects of consuming polyphenol-rich foods on endurance exercise performance. Methods: This study comprised a subanalysis of a larger systematic review. Electronic searches of Scopus, Web of Science, Ovid Medline, EMBASE and SportDiscus databases were performed. Studies were included if they involved consumption of foods containing polyphenols, and a measure of endurance exercise performance was reported. Risk of bias was assessed using the Cochrane RoB 2.0 and random effects meta-analysis was conducted, with subgroup analyses performed based on food type, sex, fitness level, and supplementation dosage and duration. Results: Data from 58 studies met eligibility criteria, with 55 studies included in the meta-analysis. Meta-analysis identified trivial but significant benefits for the overall consumption of polyphenol-rich foods on endurance exercise performance (SMD= 0.17, p<0.001). When evaluated by food type, grape, (nitrate-depleted) beetroot, French maritime pine, Montmorency cherry and pomegranate exhibited significant ergogenic effects, while no significant effects were evident for New Zealand blackcurrant, cocoa, ginseng, green tea or raisins. Significant positive effects were evident following both acute and multiple-day supplementation and meta-regression indicated that total polyphenols consumed did not moderate effect size. No effect of polyphenol consumption on exercise performance was found in females (SMD= 0.01, p=0.95), but small to moderate effects (SMD=0.21-0.76, p<0.001) were found in males across a range of fitness levels (V̇O2max 41-71 ml.kg.min-1). Limited evidence supported polyphenol-rich foods enhancing nitric oxide availability, improving vascular function, reducing oxidative damage or other physiological indicators that may explain these ergogenic benefits. Considerable heterogeneity in effect sizes of included studies was present, which may reflect variation in polyphenol bioavailability between foods, differences in study designs and subject characteristics. Discussion: Foods rich in polyphenols provide benefits for endurance exercise performance in males, but not females. These sex-specific benefits were observed across a range of fitness levels, from untrained to well-trained athletes. There is limited direct evidence of the mechanisms underpinning these effects. Other: The review protocol was registered on the Open Science Framework (https://osf.io/u7nsj). My co-authors and I acknowledge that we have no conflict of interest of relevance to the submission of this abstract.

Improving the Training of Qualified Athletes-Students by Modern Nutritiological Technologies

Currently, a significant part of highly qualified athletes are students of higher educational institutions at the same time, which manifests itself not only in an ultra-high level of physical activity, but also in significant psycho-emotional stress. Therefore, the search and introduction of modern technologies in the process of sports training, including pharmacological, hygienic, rehabilitation, etc. are continuing. An essential place among such technologies is occupied by a comprehensive methodology of nutrition-metabolic support of the training process, built on the principles of evidence-based medicine and using the latest achievements of laboratory and functional diagnostics, biochemistry and pharmacology. The purpose of the study is the formation of ideas about the necessity, validity and effectiveness of nutritive-metabolic support of the process of sports training of students of higher education institutions. Nutrition-metabolic support is part of a sporting nutritiology that possesses all the features of basic science – terms, definitions, and at the same time has great practical significance, helping to form relevant and well-grounded programs of nutrition-metabolic support of the training and competitive process of athletes, as well as to contribute to preservation the health and quality of life of athletes. This position is particularly important in student sports, where the body of an athlete is exposed to additional stressors due to the complexity of the need for a rational and effective combination of the educational and training process of highly qualified athletes. Conclusion. The applied nutritive-metabolic technologies such as methods of metabolic support of motor activity should take into account the specialization and qualifications of athletes, their gender-age characteristics and should be applied depending on the training period and the orientation of the loads. In connection with the improvement and tightening of doping control, it is extremely important that sports nutrition products and special nutritional supplements that are widely used to optimize the functional state of the athlete's body and maintain their health and quality of life do not contain substances related to the World Anti-Doping Agency Prohibited List, while ensuring a pronounced ergogenic effect

Comparison of Ergogenic Effects of Caffeine and Nitrate Supplementation on Speed, Power and Repeated Sprint Performance of Soccer Players

Caffeine and nitrates have both been reported to enhance performance in power efforts; however, it is not clear which supplement is most effective. The aim of this study was to compare the effects of caffeine and nitrates on the performance of semi-professional soccer players during different fitness tests. Ten male soccer players in a randomized crossover design were assigned to receive caffeine (5 mg/kg body mass) (CG), nitrate ((250 mL/150 mg of NO3−) (NG), or a placebo (PG) on three different occasions. In each treatment, the participants performed the following tests: 10 m and 30 m sprints, the Illinois agility test, a countermovement jump test, a squat jump test, and a repeated sprint test (6 × 40 m). Caffeine boosted performance in jumps (CMJ: CGvsPG, p = 0.018; SJ: CGvsPG, p = 0.045 and CGvsNG, p = 0.001) and limited the decrease in performance in the RSA test (CGvsPG, p = 0.012). Nitrates limited the decrease in performance in the RSA test (NGvsPG, p = 0.035). In conclusion, the two supplements limited the decrease in performance in the test of repeated sprints, with caffeine showing a greater effect. Among the other tests, only caffeine improved performance, and only in the jumps. Thus, we can conclude that supplementation with caffeine 1 h before these kinds of activities at a dosage of 5 mg/kg of body weight can enhance performance.

Extracellular Buffering Supplements to Improve Exercise Capacity and Performance: A Comprehensive Systematic Review and Meta-analysis.

Extracellular buffering supplements [sodium bicarbonate (SB), sodium citrate (SC), sodium/calcium lactate (SL/CL)] are ergogenic supplements, although questions remain about factors which may modify their effect. To quantify the main effect of extracellular buffering agents on exercise outcomes, and to investigate the influence of potential moderators on this effect using a systematic review and meta-analytic approach. This study was designed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Three databases were searched for articles that were screened according to inclusion/exclusion criteria. Bayesian hierarchical meta-analysis and meta-regression models were used to investigate pooled effects of supplementation and moderating effects of a range of factors on exercise and biomarker responses. 189 articles with 2019 participants were included, 158 involving SB supplementation, 30 with SC, and seven with CL/SL; four studies provided a combination of buffering supplements together. Supplementation led to a mean estimated increase in blood bicarbonate of + 5.2mmol L-1 (95% credible interval (CrI) 4.7-5.7). The meta-analysis models identified a positive overall effect of supplementation on exercise capacity and performance compared to placebo [ES0.5 = 0.17 (95% CrI 0.12-0.21)] with potential moderating effects of exercise typeand duration, training status and when the exercise test was performed following prior exercise. The greatest ergogenic effects were shown for exercise durations of 0.5-10min [ES0.5 = 0.18 (0.13-0.24)] and > 10min [ES0.5 = 0.22 (0.10-0.33)]. Evidence of greater effects on exercise were obtained when blood bicarbonate increases were medium (4-6mmol L-1) and large (> 6mmol L-1) compared with small (≤ 4mmol L-1) [βSmall:Medium = 0.16 (95% CrI 0.02-0.32), βSmall:Large = 0.13 (95% CrI - 0.03 to 0.29)]. SB (192 outcomes) was more effective for performance compared to SC (39 outcomes) [βSC:SB = 0.10 (95% CrI - 0.02 to 0.22)]. Extracellular buffering supplements generate large increases in blood bicarbonate concentration leading to positive overall effects on exercise, with sodium bicarbonate being most effective. Evidence for several group-level moderating factors were identified. These data can guide an athlete's decision as to whether supplementation with buffering agents might be beneficial for their specific aims.

Effectiveness of acute L-arginine supplementation on physical performance in strength training: a systematic review and meta-analysis

Background: The oral administration of L-arginine has been related to improved physical performance due to a likely reduction in muscle fatigue, resulting from the vasodilator effect of nitric oxide on skeletal muscle. However, there is no precise and quantitative analysis of the information in the literature. The main objective of this study was to assess the effectiveness of L-arginine supplementation on physical performance in strength training with a systematic review and meta-analysis. We hypothesized that L-arginine supplementation would improve performance capacity and the effects involved in strength training. Methods: The study period was from 2010 to 2020. The inclusion process established articles with well-designed human experiments that included only L-arginine supplementation (without any additional compounds) testing the effects of L-arginine supplementation on sports performance related to strength training; identical experimental conditions in placebo or control group; and publications in the last ten years (until December 31, 2020). Three studies were included that compared L-arginine supplementation with placebo in anaerobic performance tests. Test analysis supplementation with other supplements was removed and there was no gender, age, and ethnicity level. Results: There was no significant heterogeneity (p&gt;0.05) in the analysis of the three selected articles and the effects of L-arginine supplementation in muscular endurance; performance had a mean of 0.26 (95% CI = -0.129; 0.649; p = 0.190), peak torque with a mean of -0.002 (95% CI = -0.531; 0.527; p = 0. 99) of the third series of exercises and, furthermore, when comparing the integrated effect (resistance rate with the peak torque) there was no difference with a mean of 0.168 (95% CI = -0.145; 0.481; p = 0.292). Conclusions: Acute L-arginine supplementation provides no ergogenic effect on strength training performance.

The Effect of Beetroot Ingestion on High-Intensity Interval Training: A Systematic Review and Meta-Analysis.

Dietary nitrate supplementation has shown promising ergogenic effects on endurance exercise. However, at present there is no systematic analysis evaluating the effects of acute or chronic nitrate supplementation on performance measures during high-intensity interval training (HIIT) and sprint interval training (SIT). The main aim of this systematic review and meta-analysis was to evaluate the evidence for supplementation of dietary beetroot—a common source of nitrate—to improve peak and mean power output during HIIT and SIT. A systematic literature search was carried out following PRISMA guidelines and the PICOS framework within the following databases: PubMed, ProQuest, ScienceDirect, and SPORTDiscus. Search terms used were: ((nitrate OR nitrite OR beetroot) AND (HIIT or high intensity or sprint interval or SIT) AND (performance)). A total of 17 studies were included and reviewed independently. Seven studies applied an acute supplementation strategy and ten studies applied chronic supplementation. The standardised mean difference for mean power output showed an overall trivial, non-significant effect in favour of placebo (Hedges’ g = −0.05, 95% CI −0.32 to 0.21, Z = 0.39, p = 0.69). The standardised mean difference for peak power output showed a trivial, non-significant effect in favour of the beetroot juice intervention (Hedges’ g = 0.08, 95% CI −0.14 to 0.30, Z = 0.72, p = 0.47). The present meta-analysis showed trivial statistical heterogeneity in power output, but the variation in the exercise protocols, nitrate dosage, type of beetroot products, supplementation strategy, and duration among studies restricted a firm conclusion of the effect of beetroot supplementation on HIIT performance. Our findings suggest that beetroot supplementation offers no significant improvement to peak or mean power output during HIIT or SIT. Future research could further examine the ergogenic potential by optimising the beetroot supplementation strategy in terms of dosage, timing, and type of beetroot product. The potential combined effect of other ingredients in the beetroot products should not be undermined. Finally, a chronic supplementation protocol with a higher beetroot dosage (>12.9 mmol/day for 6 days) is recommended for future HIIT and SIT study.

Acute effects of two caffeine doses on bar velocity during the bench press exercise among women habituated to caffeine: a randomized, crossover, double-blind study involving control and placebo conditions

PurposeThe main goal of this study was to evaluate the effectiveness of two different doses of caffeine (3 and 6 mg/kg) to enhance bar velocity during the bench press in women habituated to caffeine.MethodsTwelve recreationally trained women (age: 23.3 ± 0.8 years, body mass: 60.7 ± 5.7 kg, bench press one-repetition maximum (1RM): 44.3 ± 7.8 kg, daily caffeine ingestion: 5.7 ± 2.0 mg/kg/day) participated in a randomized double-blind experimental design. Each participant performed four different experimental sessions: after no supplementation (control, CON), after ingesting 3 and 6 mg/kg of caffeine (CAF-3 and CAF-6, respectively), or after ingesting a placebo (PLAC). In each experimental session, the participants performed 3 sets of 3 repetitions of the bench press exercise at 50% 1RM.ResultsA two-way repeated-measures ANOVA with subsequent post hoc analyses indicated significant increases in peak velocity (p < 0.01; ES = 0.91) and mean velocity (p < 0.01; ES = 0.78) after the intake of CAF-6 compared to CON. The study did not show significant differences in bar velocity between CAF-6 and PLAC and between CAF-3 and PLAC. No significant differences in bar velocity were observed between CAF-3 and CAF-6 conditions.ConclusionThese results suggest that 6 mg/kg of caffeine can be an effective dose to improve power-specific training outcomes in women habituated to caffeine. However, the ergogenic effect of 6 mg/kg of caffeine may be derived from a combination of biological effects and expectancy, as this dose was only superior to the control condition with no differences over the placebo.

The effect of benzodiazepines on exercise in healthy adult participants: A systematic review

The use of benzodiazepines among athletes is a new and growing phenomenon according to the recent case reports published. Therefore, there is an urgent need to identify if there is rationale for the use of benzodiazepines and its effects on exercise. This review aims to provide an overview of the effects of benzodiazepine in exercise among healthy adult participants and if they might have an additional ergogenic or ergolytic effect. Electronic searches were conducted in Pubmed, Scopus and Web of Science databases up to December 2020. Search terms covered all active substance names of benzodiazepine class and search terms about sport, exercise performance and athletes. We used the Physiotherapy Evidence Database (PEDro) to assess the methodological quality of the studies included in the qualitative synthesis. The methods and planned analyses of this systematic review were pre-registered at Open Science Framework (OSF: https://osf.io/uq6j8). A total of thirty-one full articles were assessed for eligibility and ten of them were included in the qualitative analysis. We found 7 studies which investigated benzodiazepine effects after an acute dose administered, whereas only 3 studies studied long-term effects after several doses used. According to our findings it does not seem that benzodiazepines might have an ergogenic or ergolytic effect on exercise performance. The small number of articles included (n = 10) with a relatively low sample of participants (N = 16, range = 6–58) does invite us to take our results with caution. This review evidences valuable insights into the use of benzodiazepines from a physical performance point of view. Our findings highlight the unclear effects benzodiazepines might have on exercise performance and its possible mechanisms of actions. Hence, the need to conduct new studies to understand its possible effects becomes essential to protect the health of athletes of all levels.

Effects of Music on Resistance Exercise Performance: A Narrative Review

ABSTRACT This review aimed to summarize and critically evaluate the research on the effects of music on resistance exercise performance. Research in the field has consistently demonstrated an ergogenic effect of music on resistance exercise performance. Specifically, studies have reported that listening to music pre-exercise or during exercise may enhance handgrip strength, muscle endurance, velocity, and power. Although a performance-enhancing benefit has been observed in many (but not all studies), several factors such as music tempo, volume, and genre preference may modulate the ergogenic effect of music. An ergogenic effect is commonly reported with faster tempo music (&gt;120 bpm) set to muscle volume of 70–80 decibels. Using individual preference regarding music genre seems to produce the most consistent performance-enhancing effect. Besides these factors, lyrical content, harmony, and melody are also factors that may determine the ergogenic potential of music. By using some of the recommendations outlined herein, individuals may harness and optimize the ergogenic effects of music on resistance exercise performance.

The effect of branched-chain amino acid on muscle damage markers and performance following strenuous exercise: a systematic review and meta-analysis.

This systematic review and meta-analysis determined whether the ergogenic effects of branched-chain amino acids (BCAA) ameliorated markers of muscle damage and performance following strenuous exercise. In total, 25 studies were included, consisting of 479 participants (age 24.3 ± 8.3 years, height 1.73 ± 0.06 m, body mass 70.8 ± 9.5 kg, females 26.3%). These studies were rated as fair to excellent following the PEDro scale. The outcome measures were compared between the BCAA and placebo conditions at 24 and 48 hours following muscle-damaging exercises, using standardised mean differences and associated p-values via forest plots. Our meta-analysis demonstrated significantly lower levels of indirect muscle damage markers (creatine kinase, lactate dehydrogenase and myoglobin) at 48 hours post-exercise (standardised mean difference [SMD] = -0.41; p < 0.05) for the BCAA than placebo conditions, whilst muscle soreness was significant at 24 hours post-exercise (SMD = -0.28 ≤ d ≤ -0.61; p < 0.05) and 48 hours post-exercise (SMD = -0.41 ≤ d≤ -0.92; p < 0.01). However, no significant differences were identified between the BCAA and placebo conditions for muscle performance at 24 or 48 hours post-exercise (SMD = 0.08 ≤ d ≤ 0.21; p > 0.05). Overall, BCAA reduced the level of muscle damage biomarkers and muscle soreness following muscle-damaging exercises. However, the potential benefits of BCAA for muscle performance recovery is questionable and warrants further investigation to determine the practicality of BCAA for ameliorating muscle damage symptoms in diverse populations. PROSPERO registration number: CRD42020191248. Novelty: BCAA reduces the level of creatine kinase and muscle soreness following strenuous exercise with a dose-response relationship. BCAA does not accelerate recovery for muscle performance.

Effects of Caffeine on Performance During High- and Long-Jump Competitions.

To investigate the effects of caffeine (CAF) on performance during high- and long-jump competitions. Using a crossover and double-blind design, 6 well-trained high jumpers and 6 well-trained long jumpers performed a simulation of a high- and long-jump competition 60minutes after ingesting a capsule containing either 5mg·kg-1 body mass of anhydrous CAF or a placebo. The high jumps were video recorded for kinematic analysis. The velocity during the approach run of the long jump was also monitored using photocells. CAF improved jump performance (ie,the highest bar height overlap increased by 5.1% [2.3%], P = .008), as well as enhancing the height displacement of the central body mass (+1.3% [1.7%], P = .004) compared with the placebo. CAF had no ergogenic effect on jump distance (P = .722); however, CAF increased the velocity during the last 10m of the long jump (P = .019), and the percentage of "foul jumps" was higher than that expected by chance in the CAF group (80.5% [12.5%], χ2 = 13.44, P < .001) but not in the cellulose condition (58.3% [22.9%], χ2 = 1.48, P = .224). CAF ingestion (5mg·kg-1 body mass) improves high-jump performance but seems to negatively influence technical aspects during the approach run of the long jump, resulting in no improvement in long-jump performance. Thus, CAF can be useful for jumpers, but the specificity of the jump competition must be taken into account.

Effects of wearing a customized bite-aligning mouthguard on powerful actions in highly trained swimmers

Background/objectivesThe potential advantages of wearing customized bite-aligning mouthguards on several performance parameters such as muscular strength, power and reaction time have been reported. Literature shows that the concurrent activation potentiation phenomenon, elicited by a powered and balanced jaw clenching, can provide athletes with several neuromuscular advantages. The aim of the present study was to investigate the acute effects of jaw clenching while wearing a customized bite-aligning mouthguard on swimming start, countermovement jump and swim bench test, in contrast to two other conditions: non-jaw clenching and jaw clenching without mouthguard. MethodsA randomized, repeated measure within study design was used to compare the condition effect on eight highly trained elite male and female swimmers. ResultsStatistical analysis revealed a significant increase in the countermovement jump height (p = 0.041) when comparing the use of mouthguards with the non-jaw condition. In the swim bench, a significant greater time to peak force (p = 0.049) was found when comparing the use of mouthguards with the jaw condition. Although, non-significant effects, small differences were found in the start reaction time and 15-m freestyle swimming when comparing the use of mouthguards with the non-jaw condition. ConclusionThis study demonstrated that wearing customized, bite-aligning mouthguards had an ergogenic effect on specific measures of vertical jump and swim bench test, whereas non-meaningful but small differences were found in swimming start.

Achieving an Optimal Fat Loss Phase in Resistance-Trained Athletes: A Narrative Review

Managing the body composition of athletes is a common practice in the field of sports nutrition. The loss of body weight (BW) in resistance-trained athletes is mainly conducted for aesthetic reasons (bodybuilding) or performance (powerlifting or weightlifting). The aim of this review is to provide dietary–nutritional strategies for the loss of fat mass in resistance-trained athletes. During the weight loss phase, the goal is to reduce the fat mass by maximizing the retention of fat-free mass. In this narrative review, the scientific literature is evaluated, and dietary–nutritional and supplementation recommendations for the weight loss phase of resistance-trained athletes are provided. Caloric intake should be set based on a target BW loss of 0.5–1.0%/week to maximize fat-free mass retention. Protein intake (2.2–3.0 g/kgBW/day) should be distributed throughout the day (3–6 meals), ensuring in each meal an adequate amount of protein (0.40–0.55 g/kgBW/meal) and including a meal within 2–3 h before and after training. Carbohydrate intake should be adapted to the level of activity of the athlete in order to training performance (2–5 g/kgBW/day). Caffeine (3–6 mg/kgBW/day) and creatine monohydrate (3–5 g/day) could be incorporated into the athlete’s diet due to their ergogenic effects in relation to resistance training. The intake of micronutrients complexes should be limited to special situations in which there is a real deficiency, and the athlete cannot consume through their diet.

Music Augmented With Isochronic Auditory Beats or Vibrotactile Stimulation Does Not Affect Subsequent Ergometer Cycling Performance: A Pilot Study.

Methods to enhance the ergogenic effects of music are of interest to athletes of all abilities. The aim of this pilot study was to investigate the ergogenic effects of two commercially available methods of music augmentation: auditory beats and vibrotactile stimulation. Six male and five female cyclists/triathletes cycled for 7 minutes at three different intensities: a rate of perceived exertion (RPE) of 11 (“light”), RPE of 15 (“hard”), and a 7-minute time-trial. Before each 7-minute bout of cycling, participants listened to 10 minutes of self-selected music (MUS), or the same music with the addition of either isochronic auditory beats (ABS) or vibrotactile stimulation via SUBPACTM (VIB). MUS, ABS and VIB trials were performed in a randomized order. Power output was measured during cycling and felt arousal and feeling scores were recorded at timepoints throughout the protocol. The results found the augmented MUS interventions did not influence power output with no significant main effect of trial (p = 0.44, η2 = 0.09) or trial × cycling intensity interaction (p = 0.11, η2 = 0.20). Similarly, both felt arousal and feeling scores were unchanged between the MUS, ABS, and VIB trials (p > 0.05). In conclusion, this pilot study indicated an ineffectiveness of the ABS and VIB to affect subsequent 7-min cycling performance compared to self-selected MUS alone.

Influence of Higenamine on Exercise Performance of Recreational Female Athletes: A Randomized Double-Blinded Placebo-Controlled Trial.

The aim of this study was to determine the ergogenic effects and the safety profile of a one-component higenamine supplement in female recreational athletes. Twelve recreational female basketball players (age 29–41 years, oxygen consumption (VO2max) > 30 ml⋅kg–1⋅min–1, with training > 5 h wk–1) were randomized either to the higenamine group, or to the placebo group for 3 weeks. In order to determine ergogenic effects and safety profile of higenamine administration, we assessed the following variables before and after 3 weeks of supplementation: anthropometric parameters, resting metabolic rate (RMR), exercise testing variables, serum free fatty acids (FFAs), blood pressure, enzyme activity, urea, lipid profile, and complete blood count. There were no differences between groups in anthropometric parameters, including basal metabolic rate (BMR), RMR and body fat [p = 0.706 (Cohen’s d 0.223), p = 0.169 (Cohen’s d 0.857), and p = 0.223 (Cohen’s d 0.750), respectively], FFAs [0.43 ± 0.03 vs. 0.54 ± 0.23, p = 0.206 (Cohen’s d 0.540)], neither significant differences in cardiopulmonary parameters after the intervention period. Furthermore, all measured outcome variables in the safety assessment were not significant, with values remaining stable during the intervention period for participants in both groups. This is the first study to document the effects and the safety profile of higenamine-based dietary supplements at a specified dose in female recreational athletes. Our data indicate that 21-day of supplementation with 75 mg higenamine would not result in improving cardiopulmonary exercise fitness and weight loss in female recreational athletes. Moreover, supplementation with 75 mg higenamine is safe and well-tolerated in younger recreational female athletes.

Effects of Paracetamol (Acetaminophen) Ingestion on Endurance Performance: A Systematic Review and Meta-Analysis.

Several studies explored the effects of paracetamol (acetaminophen) ingestion on endurance performance, but their findings are conflicting. Therefore, this review aimed to conduct a meta-analysis examining the effects of paracetamol ingestion on endurance performance. Five databases were searched to find relevant studies. The PEDro checklist was used to assess the methodological quality of the included studies. Data reported in the included studies were pooled in a random-effects meta-analysis. A total of ten studies with good or excellent methodological quality were included in the meta-analysis (pooled n = 141). All included studies had a randomized, double-blind, crossover design. In the main meta-analysis, there was no significant difference between the effects of placebo and paracetamol on endurance performance (Cohen’s d = 0.09; 95% confidence interval (CI): −0.04, 0.22; p = 0.172). However, an ergogenic effect was found when we considered only the studies that provided paracetamol 45 to 60 min before exercise (Cohen’s d = 0.14; 95% CI: 0.07, 0.21; p < 0.001). In a subgroup analysis that focused on time-to-exhaustion tests, there was a significant ergogenic effect of paracetamol ingestion (Cohen’s d = 0.19; 95% CI: 0.06, 0.33; p = 0.006). There was no significant difference between placebo and paracetamol in a subgroup analysis that focused on time trial tests (Cohen’s d = 0.05; 95% CI: −0.12, 0.21; p = 0.561). In conclusion, paracetamol ingestion appears to enhance performance (a) in time-to-exhaustion endurance tests and (b) when consumed 45 to 60 min before exercise.

Caffeine improves work durability and physical performance in anaerobic exercises among active adults in Tripoli Lebanon

BackgroundPeople worldwide have a high intake of caffeine. Active adults are among the group of people who have always been interested in caffeine as an ergogenic aid. This study aims at examining the association between caffeine consumption and perceived performance (aerobic and anaerobic exercises) among active people attending different gyms in Tripoli, Lebanon.MethodsA cross-sectional study was conducted on 206 participants attending seven gyms in Tripoli. Participants were recruited using simple random sampling for a face-to-face individual interview. Data were collected using a semi-structured questionnaire. Data have been coded, entered, and analyzed using SPSS software.ResultsThe prevalence rate of active people practicing both aerobic and anaerobic exercises is 63.6%. More than half of our sample (54.8%) has been working out for a duration of more than 6 months and 84.6% of respondents spend at least 30 min during their workouts. Caffeine consumption was popular in our sample with 92.2% indicating that they use caffeinated products. The findings of this study showed an association between anaerobic exercise and caffeine, perceived as physical performance enhancer and work durability enhancer. Yet no association was found between aerobic exercise and caffeine consumption.ConclusionsPerhaps, future research could focus on the safe doses of caffeine that could be given for anaerobic exercises to have an ergogenic effect. This could help us to build scientific guidelines for caffeine’s association with sports performance.

Effect of Oral Supplementation with L-Carnitine on Performance Time in a 5000 m Race and Responses of Free Fatty Acid and Carnitine Concentrations in Trained-Endurance Athletes

This study was designed to determine the effect of oral supplementation with L-carnitine on the performance time in a 5000 m race. In addition, free fatty acid, blood carnitine, lactate, and glucose responses to the race following the supplementation period were measured. Twenty male trained-endurance athletes were randomly divided into two groups (L-carnitine, n = 10 (22.13 ± 2.66 yrs) or placebo, n = 10 (21.63 ± 2.23 yrs)). The study was performed with a randomized, double-blind, placebo-controlled parallel-group, in which participants ingested an L-carnitine supplement or a placebo 2 × 1.5 g/day for 3 weeks. Athletes completed a 5000 m race before and after the supplementation period. Blood samples were collected from each athlete before and after the race, preand post-supplementation to measure the physiological responses. Data showed that there were no differences in performance time before (p=0.624) and after (p=0.407) supplementation period between groups and within a group (p&gt;0.05). No differences existed in physiological responses between groups after supplementation before beginning the race (p&gt;0.05), except for the blood carnitine level, which was significantly higher in the L-carnitine than the placebo (P=0.001) group. After the finish of the race, however, data showed better physiological responses in response to L-carnitine supplementation compared to the placebo group (p&lt;0.05). In conclusion, although L-carnitine supplementation increases blood carnitine concentration, it has no beneficial effect on performance time of 5000 m race probably due to the short duration of the race; it might also have no ergogenic effect.

Acute Effects of the Wim Hof Breathing Method on Repeated Sprint Ability: A Pilot Study.

The Wim Hof breathing method (WHBM) combines periods of hyperventilation (HV) followed by voluntary breath-holds (BH) at low lung volume. It has been increasingly adopted by coaches and their athletes to improve performance, but there was no published research on its effects. We determined the feasibility of implementing a single WHBM session before repeated sprinting performance and evaluated any acute ergogenic effects. Fifteen amateur runners performed a single WHBM session prior to a Repeated Ability Sprint Test (RAST) in comparison to voluntary HV or spontaneous breathing (SB) (control) in a randomized cross-over design. Gas exchange, heart rate, and finger pulse oxygen saturation (SpO2) were monitored. Despite large physiological effects in the SpO2 and expired carbon dioxide (VCO2) levels of both HV and WHBM, no significant positive or negative condition effects were found on RAST peak power, average power, or fatigue index. Finger SpO2 dropped to 60 ± 12% at the end of the BHs. Upon the last HV in the WHBM and HV conditions, end-tidal CO2 partial pressure (PETCO2) values were 19 ± 3 and 17 ± 3 mmHg, indicative of respiratory alkalosis with estimated arterial pH increases of +0.171 and of +0.181, respectively. Upon completion of RAST, 8 min cumulated expired carbon dioxide volumes in the WHBM and HV were greater than in SB, suggesting lingering carbon dioxide stores depletion. These findings indicate that despite large physiological effects, a single WHBM session does not improve anaerobic performance in repeated sprinting exercise.