Acute Capsaicin Supplementation Improves Resistance Training Performance in Trained Men

Acute effects of multi-ingredient pre-workout dietary supplement on anaerobic performance in untrained men: a randomized, crossover, single blind study

BACKGROUND

Multi-ingredient pre-workout dietary supplements (MIPS), which are combinations of different ingredients acting on different physiological mechanisms, can have a synergistic effect and improve performance. The aim of the study was to determine the acute effects of a multi-ingredient pre-workout supplement containing: beta-alanine, taurine, caffeine, L-tyrosine, and cayenne pepper (capsaicin) on anaerobic performance.

METHODS

A randomized, crossover, single-blind study was designed. Twelve young, healthy, untrained men aged 22.4 ± 1.44 years participated in the study. The participants performed a supramaximal all-out test (20 s Wingate test) twice, day by day, in random order: test after placebo or MIPS consumption. In both trials, the following variables were measured in the exercise test: total work performed, peak power, mean power, time to reach peak power, and power decrease.

RESULTS

MIPS was found to be effective in improving peak power (p = 0.009, ES = 0.77) and mean power (p = 0.04, ES = 0.62) in the Wingate test. However, the supplement consumption did not affect the amount of total work done (p = 0.10, ES = 0.48) in the test or power decrease (p = 0.07, ES = 0.53). The data indicate, that the improvement in anaerobic power was due to a significant improvement in pedaling speed, which was manifested in a significant improvement (i.e. shortening) in time to peak power (p = 0.003, ES = 0.88).

CONCLUSION

A multi-ingredient pre-workout dietary supplement was found to be effective in improving Wingate (anaerobic) performance.

TRIAL REGISTRATION

NCT06363669, retrospectively registered on 11.04.2024 (ClinicalTrials.gov).

Muscle Strength Preservation During Repeated Sets of Fatiguing Resistance Exercise: A Secondary Analysis

ABSTRACT

Nuzzo, JL. Muscle strength preservation during repeated sets of fatiguing resistance exercise: A secondary analysis. J Strength Cond Res 38(6): 1149-1156, 2024-During sustained or repeated maximal voluntary efforts, muscle fatigue (acute strength loss) is not linear. After a large initial decrease, muscle strength plateaus at approximately 40% of baseline. This plateau, which likely reflects muscle strength preservation, has been observed in sustained maximal isometric and repeated maximal isokinetic contractions. Whether this pattern of fatigue occurs with traditional resistance exercise repetitions with free weights and weight stack machines has not been overviewed. Here, the aim was to determine whether the number of repetitions completed across 4 or more consecutive repetitions-to-failure tests exhibits the same nonlinear pattern of muscle fatigue. A secondary analysis was applied to data extracted as part of a recent meta-analysis on repetitions-to-failure tests. Studies were eligible if they reported mean number of repetitions completed in 4-6 consecutive repetitions-to-failure tests at a given relative load. Twenty-nine studies were included. Overall, the results show that the number of repetitions completed in consecutive repetitions-to-failure tests at a given load generally decreases curvilinearly. The numbers of repetitions completed in sets 2, 3, 4, 5, and 6 were equal to approximately 70, 55, 50, 45, and 45% of the number of repetitions completed in set 1, respectively. Longer interset rest intervals typically attenuated repetition loss, but the curvilinear pattern remained. From the results, a chart was created to predict the number of repetitions across 6 sets of resistance exercise taken to failure based on the number of repetitions completed in set 1. The chart is a general guide and educational tool. It should be used cautiously. More data from a variety of exercises, relative loads, and interset rest intervals are needed for more precise estimates of number of repetitions completed during repeated sets of fatiguing resistance exercise.

A natural sustained-intestinal release formulation of red chili pepper extracted capsaicinoids (Capsifen®) safely modulates energy balance and endurance performance: a randomized, double-blind, placebo-controlled study

Introduction

Overweight and obesity are major public health concerns, with a sharp increase in prevalence over the last few decades. The primary cause is an imbalance between calorie intake and expenditure due to a rise in calorie-rich processed food and reduced physical activity. Energy balance in humans involves complex processes including thermogenesis, a crucial factor in regulating energy expenditure.

Methods

In this randomized, double-blinded, placebo-controlled three-arm three-sequence study, we investigated the efficacy of Capsifen® (CapF), a pungency-masked sustained-intestinal release formulation of red chili extract, on energy expenditure, fat oxidation, and endurance using the Quark C-PET system in healthy overweight participants, with and without exercise. In the study, 105 healthy participants were randomized to receive either placebo, CapF 100 mg/day, or CapF 200 mg/day for 28 days.

Results

CapF demonstrated a dose-dependent response to increased energy expenditure and fatty acid oxidation with a concomitant reduction in body weight. Both CapF 100 and CapF 200 also increased the time to exhaustion.

Discussion

These results demonstrate the plausible efficacy of CapF in energy expenditure and physical performance in otherwise healthy adults who have a high body mass index.

Clinical trial registration

https://ctri.nic.in/Clinicaltrials/pmaindet2.php?EncHid=MjQzNTg=&Enc=&userName=CTRI/2018/04/013157 dated 04 October 2018.

Ten weeks of Capsicum annuum L. extract supplementation did not change adipose tissue-derived hormones, appetite, body composition, and muscle strength when combined with resistance training in healthy untrained men: A clinical trial study

Capsiate (CAP) is a nonpungent capsaicin analog (Capsicum annuum L. extract) that has been studied as a potential antiobesity agent. However, the interaction between chronic CAP supplementation and resistance training is not clear. The purpose of this study was to examine the changes in adipose tissue-derived hormones, body composition, appetite, and muscle strength after 10 weeks of resistance training, combined with chronic CAP supplementation in healthy untrained men. We hypothesized that CAP could induce higher benefits when combined with resistance training after 10 weeks of intervention compared to resistance training alone. Twenty-four young men (age, 22.0 ± 2.9) were randomized to either capsiate supplementation (CAP = 12 mg/day) or placebo (PL), and both groups were assigned to resistance training. Body composition, leptin and adiponectin concentrations, subjective ratings of appetite, energy intake, and exercise performance were assessed at before and after 10 weeks of progressive resistance training. There was a significant increase in body mass (P < .001), fat-free mass (CAP: 58.0 ± 7.1 vs. post, 59.7 ± 7.1 kg; PL: pre, 58.4 ± 7.3 vs. post, 59.8 ± 7.1 kg; P < .001), resting metabolic rate (CAP: pre, 1782.9 ± 160.6 vs. post, 1796.3 ± 162.0 kcal; PL: pre, 1733.0 ± 148.9 vs. post, 1750.5 ± 149.8 kcal; P < .001), maximal strength at 45 leg press (P < .001) and bench press (P < .001) in both groups, but no significant (P > .05) supplementation by training period interaction nor fat mass was observed. For subjective ratings of appetite, energy intake, leptin, and adiponectin, no significant effect of supplementation by training period interaction was observed (P > .05). In conclusion, 10 weeks of resistance training increased total body weight, muscle mass, and maximum strength in healthy untrained men; however, CAP supplementation (12 mg, 7 days per week) failed to change adipose tissue-derived hormones, appetite, body composition and muscle strength in this population. Registered under Brazilian Registry of Clinical Trials (RBR-8cz9kfq).

Maximal Number of Repetitions at Percentages of the One Repetition Maximum: A Meta-Regression and Moderator Analysis of Sex, Age, Training Status, and Exercise

The maximal number of repetitions that can be completed at various percentages of the one repetition maximum (1RM) [REPS ~ %1RM relationship] is foundational knowledge in resistance exercise programming. The current REPS ~ %1RM relationship is based on few studies and has not incorporated uncertainty into estimations or accounted for between-individuals variation. Therefore, we conducted a meta-regression to estimate the mean and between-individuals standard deviation of the number of repetitions that can be completed at various percentages of 1RM. We also explored if the REPS ~ %1RM relationship is moderated by sex, age, training status, and/or exercise. A total of 952 repetitions-to-failure tests, completed by 7289 individuals in 452 groups from 269 studies, were identified. Study groups were predominantly male (66%), healthy (97%), < 59 years of age (92%), and resistance trained (60%). The bench press (42%) and leg press (14%) were the most commonly studied exercises. The REPS ~ %1RM relationship for mean repetitions and standard deviation of repetitions were best described using natural cubic splines and a linear model, respectively, with mean and standard deviation for repetitions decreasing with increasing %1RM. More repetitions were evident in the leg press than bench press across the loading spectrum, thus separate REPS ~ %1RM tables were developed for these two exercises. Analysis of moderators suggested little influences of sex, age, or training status on the REPS ~ %1RM relationship, thus the general main model REPS ~ %1RM table can be applied to all individuals and to all exercises other than the bench press and leg press. More data are needed to develop REPS ~ %1RM tables for other exercises.

A single dose of dihydrocapsiate does not improve neuromuscular performance in resistance-trained young adults: A randomised, triple-blinded, placebo-controlled, crossover trial

Capsinoids may exert ergogenic effects on resistance exercises. However, the acute effects of capsinoids on neuromuscular performance in humans are unknown. Here, we aimed to investigate the acute effects of dihydrocapsiate on lower- and upper-body neuromuscular performance parameters in resistance-trained individuals. 25 young adults (n = 6 women; age = 26 ± 3 years; body mass index = 24.3 ± 2.8 kg/m2) with ≥ 1-year resistance training experience were included in this triple-blind (participants, intervention researchers, and data analysts were blinded), placebo-controlled, crossover study. Lower- and upper-body ballistic strength (countermovement jump [CMJ] height and bench press throw [BPT] peak velocity), maximum dynamic strength (estimated 1 repetition maximum in squat and bench press [BP]), and strength-endurance (mean set velocity [squat] and number of repetitions to failure [bench press]) were assessed in 2 independent sessions (≥7 days separation). Participants ingested 12 mg of dihydrocapsiate or placebo 30 min before each trial. We found no significant differences between dihydrocapsiate and placebo conditions in ballistic strength, (CMJ height 33.20 ± 8.07 vs 33.32 ± 7.85 cm; BPT peak velocity 2.82 ± 0.77 vs 2.82 ± 0.74 m/s) maximal dynamic strength (estimated squat 1RM: 123.76 ± 40.63 vs 122.66 ± 40.97 kg; estimated BP 1RM: 99.47 ± 43.09 vs 99.60 ± 43.34 kg), and strength-endurance (squat mean set velocity 0.66 ± 0.07 vs 0.66 ± 0.05 m/s; number BP repetitions to failure 13.00 ± 3.56 vs 13.00 ± 4.78) (all P ≥ 0.703). We conclude that dihydrocapsiate does not acutely improve neuromuscular performance in trained young adults.

Effects of different phenylcapsaicin doses on neuromuscular activity and mechanical performance in trained male subjects: a randomized, triple-blinded, crossover, placebo-controlled trial

Objective: This study aimed to examine the effects of phenylcapsaicin (PC) supplementation on strength performance and neuromuscular activity in young trained male subjects. Materials and methods: A total of 25 trained subjects [full-squat (SQ) one repetition maximum (1RM) = 125.6 ± 21.0 kg] were enrolled in this randomized, triple-blinded, crossover, placebo-controlled trial. The subjects performed a first session and a post-24 h session for each condition. In the first session, the subjects ingested a high dose of PC (HD, 2.5 mg), a low dose (LD, 0.625 mg), or a placebo (PLA). Their performance in SQ was assessed under a 3% × 8 × 70% 1RM protocol in the first session. Their performances in countermovement jump (CMJ), SQ with 60% 1RM, and isometric squat were measured before and after the SQ protocol in both sessions. The neural activity of the vastus lateralis (VL) and vastus medialis (VM) was recorded via surface electromyography (EMG) and averaged in both sessions. Results: Significant differences between the conditions were reported for lifting velocity, velocity loss, and the 60% load in dynamic SQ (p range = 0.02-0.04). Electrical changes were not identified for any outcome, although neural activity changed across time (p range ≤0.001-0.006). A significant condition × time effect was observed in CMJ compared to PLA (p ≤0.001) and LD (p ≤0.001). Intra-set analyses revealed higher velocities in HD compared to those in LD (p = 0.01) and PLA (p range = 0.004-0.008). Conclusion: Therefore, PC may improve the strength performance and attenuate the mechanical fatigue induced by resistance training in SQ and CMJ exercises.

Effects of phenylcapsaicin on aerobic capacity and physiological parameters in active young males: a randomized, triple-blinded, placebo-controlled, crossover trial

Objective: Phenylcapsaicin (PC) is a new capsaicin analog which has exhibited a higher bioavailability. This sudy assessed the effects of a low dose (LD) of 0.625 mg and a high dose (HD) of 2.5 mg of PC on aerobic capacity, substrate oxidation, energy metabolism and exercise physiological variables in young males. Materials and methods: Seventeen active males (age = 24.7 ± 6.0 years) enrolled to this randomized, triple-blinded, placebo-controlled, crossover trial. Participants attended the laboratory on 4 sessions separated by 72-96 h. A submaximal exercise test [to determine maximal fat oxidation (MFO) and the intensity at MFO (FATmax)] followed by a maximal incremental test (to determine VO2_max) were performed in a preliminary session. The subsequent sessions only differed in the supplement ingested [LD, HD or placebo (PLA)] and consisted of a steady-state test (60 min at FATmax) followed by a maximal incremental test. Energy metabolism, substrate oxidation, heart rate, general (gRPE) and quadriceps (RPEquad) rate of perceived exertion, skin temperature and thermal perception were tested. Results: Clavicle thermal perception was lower in HD compared to PLA and LD (p = 0.04) across time. HD reduced maximum heart rate in comparison to PLA and LD (p = 0.03). LD reported higher general RPE (RPEg) values during the steady-state test compared to PLA and HD across time (p = 0.02). HD and LD elicited higher peak of fat oxidation during the steady-state test compared with PLA (p = 0.05). Intra-test analyses revealed significant differences for fat oxidation (FATox) in favor of HD and LD compared to PLA (p = 0.002 and 0.002, respectively), and for carbohydrate oxidation (CHOox) (p = 0.05) and respiratory exchange ratio (RER) (p = 0.03) for PLA. In the incremental test, only general RPE at 60% of the maximal intensity (W) differed favoring HD (p ≤ 0.05). Conclusion: Therefore, PC may contribute to increase aerobic capacity through the improvement of fat oxidation, maximum heart rate and perceptual responses during exercise.

Effects of Capsaicin and Capsiate on Endurance Performance: A Meta-Analysis

Several studies have explored the effects of capsaicin and capsiate on endurance performance, with conflicting findings. This systematic review aimed to perform a meta-analysis examining the effects of capsaicin and capsiate vs. placebo on endurance performance in humans. Seven databases were searched to find eligible studies. The effects of capsaicin and capsiate on aerobic endurance (e.g., time-trials or time-to-exhaustion tests), muscular endurance (e.g., repetitions performed to muscular failure), and rating of perceived exertion (RPE) were examined in a random-effects meta-analysis. Fourteen studies (n = 183) were included in the review. Most studies provided capsaicin or capsiate in the dose of 12 mg, 45 min before exercise. In the meta-analysis for aerobic endurance, there was no significant difference between the placebo and capsaicin/capsiate conditions (Cohen’s d: 0.04; 95% confidence interval: −0.16, 0.25; p = 0.69). In subgroup meta-analyses, there were no significant differences between the placebo and capsaicin/capsiate conditions when analyzing only studies that used time-trials (p = 0.20) or time-to-exhaustion tests (p = 0.80). In the meta-analysis for muscular endurance, a significant ergogenic effect of capsaicin/capsiate was found (Cohen’s d: 0.27; 95% confidence interval: 0.10, 0.43; p = 0.002). When analyzing set-specific effects, an ergogenic effect of capsaicin/capsiate was found in set 1, set 2, and set 3 (Cohen’s d: 0.21–29). Capsaicin/capsiate ingestion reduced RPE following muscular endurance (p = 0.03) but not aerobic endurance tests (p = 0.58). In summary, capsaicin/capsiate supplementation acutely enhances muscular endurance, while the effects on aerobic endurance are less clear.

Acute Supplementation with Capsaicin Enhances Upper-Limb Performance in Male Jiu-Jitsu Athletes

The present study investigated whether acute capsaicin (CAP) supplementation improves mean power output (MPO) and peak velocity (PV) during the performance of the free bench press exercise (FBP). Twelve (n = 12) male Brazilian Jiu-Jitsu (BJJ) athletes (age: 24.3 ± 1.5 years, height: 1.74 ± 0.1 m, body mass: 75.7 ± 10.1 kg) participated in this randomized, placebo (PLA)-controlled, double-blind, crossover trial. For each condition, 45 min after CAP (12 mg purified) or PLA (12 mg of Celulomax E) consumption, the participants performed four sets of five repetitions of FBP at a load of 60% of body mass with five-min rest intervals. The MPO (t = 5.6, df = 11, p = 0.001, EF = 0.3, IC 95% = −0.55 to 1.05) and PV (t = 5.4, df = 11, p = 0.001, EF = 0.5, IC 95% = −0.32 to 1.30) were significantly higher with CAP supplementation versus PLA. Acute CAP supplementation appears to improve MPO and PV during FBP in male BJJ athletes.

Capsaicin and Its Effect on Exercise Performance, Fatigue and Inflammation after Exercise

Capsaicin (CAP) activates the transient receptor potential vanilloid 1 (TRPV1) channel on sensory neurons, improving ATP production, vascular function, fatigue resistance, and thus exercise performance. However, the underlying mechanisms of CAP-induced ergogenic effects and fatigue-resistance, remain elusive. To evaluate the potential anti-fatigue effects of CAP, 10 young healthy males performed constant-load cycling exercise time to exhaustion (TTE) trials (85% maximal work rate) after ingestion of placebo (PL; fiber) or CAP capsules in a blinded, counterbalanced, crossover design, while cardiorespiratory responses were monitored. Fatigue was assessed with the interpolated twitch technique, pre-post exercise, during isometric maximal voluntary contractions (MVC). No significant differences (p > 0.05) were detected in cardiorespiratory responses and self-reported fatigue (RPE scale) during the time trial or in TTE (375 ± 26 and 327 ± 36 s, respectively). CAP attenuated the reduction in potentiated twitch (PL: -52 ± 6 vs. CAP: -42 ± 11%, p = 0.037), and tended to attenuate the decline in maximal relaxation rate (PL: -47 ± 33 vs. CAP: -29 ± 68%, p = 0.057), but not maximal rate of force development, MVC, or voluntary muscle activation. Thus, CAP might attenuate neuromuscular fatigue through alterations in afferent signaling or neuromuscular relaxation kinetics, perhaps mediated via the sarco-endoplasmic reticulum Ca2+ ATPase (SERCA) pumps, thereby increasing the rate of Ca2+ reuptake and relaxation.

Effects of Capsiate Supplementation on Maximal Voluntary Contraction in Healthy Men

This study aimed to investigate the effects of acute capsaicin analog (Capsiate - CAP) supplementation on maximal voluntary isometric contraction (MVIC) performance in healthy young men. Thirteen subjects (25.2±3.2 yrs) participated in the present study. In two different days separated by one week, the subjects ingested capsiate (12 mg) or placebo (starch: 12 mg) 45 minutes before a MVIC test. The MVIC test consisted of five 10-second knee extension maximal isometric contractions with 45 seconds of recovery between efforts. The peak force, mean force, minimum force, fatigue index, and area under the curve of each contraction were calculated. Main condition effect was found, with higher values of peak force (+4.83%, F=6.867, p=0.02), fatigue index (+8.96%, F=5.228, p=0.041), and area under the curve (+4.19%, F=4.774, p=0.04) for CAP compared to placebo, however, no interaction effect was found for any variable (F=0.090 to 1.356, p≥0.276). In summary, healthy young men produced higher maximal isometric force and delayed fatigue in the CAP condition compared to placebo condition (condition effect) but without significant difference between each effort.

Mechanisms of Physical Fatigue and its Applications in Nutritional Interventions

Physical fatigue during exercise can be defined as an impairment of physical performance. Multiple factors have been found contributing to physical fatigue, including neurotransmitter-mediated defense action, insufficient energy supply, and induction of oxidative stress. These mechanistic findings provide a sound theoretical rationale for nutritional intervention since most of these factors can be modulated by nutrient supplementation. In this review, we summarize the current evidence regarding the functional role of nutrients supplementation in managing physical performance and propose the issues that need to be addressed for better utilization of nutritional supplementation approach to improve physical performance.

Chronic capsiate supplementation increases fat-free mass and upper body strength but not the inflammatory response to resistance exercise in young untrained men: a randomized, placebo-controlled and double-blind study

BACKGROUND

Acute capsaicinoid and capsinoid supplementation has endurance and resistance exercise benefits; however, if these short-term performance benefits translate into chronic benefits when combined with resistance training is currently unknown. This study investigated changes of chronic Capsiate supplementation on muscular adaptations, inflammatory response and performance in untrained men.

METHODS

Twenty untrained men were randomized to ingest 12 mg Capsiate (CAP) or placebo in a parallel, double-blind design. Body composition and performance were measured at pre-training and after 6 weeks of resistance training. An acute resistance exercise session test was performed pre and post-intervention. Blood samples were collected at rest and post-resistance exercise to analyze Tumor necrosis factor- (TNF-), Soluble TNF- receptor (sTNF-r), Interleukin-6 (IL-6) and Interleukin-10 (IL-10).

RESULTS

Exercise and CAP supplementation increased fat-free mass in comparison to baseline by 1.5 kg (P < 0.001), however, the majority of the increase (1.0 kg) resulted from an increase in total body water. The CAP change scores for fat-free mass were significantly greater in comparison to the placebo (CAP ∆%= 2.1 ± 1.8 %, PLA ∆%= 0.7 ± 1.3 %, P = 0.043) and there was a significant difference between groups in the bench press exercise (P = 0.034) with greater upper body strength change score for CAP (∆%= 13.4 ± 9.1 %) compared to placebo (∆%= 5.8 ± 5.2 %), P = 0.041. CAP had no effect on lower body strength and no supplementation interactions were observed for all cytokines in response to acute resistance exercise (P > 0.05).

CONCLUSION

Chronic Capsiate supplementation combined with resistance training during short period (6 weeks) increased fat-free mass and upper body strength but not inflammatory response and performance in young untrained men.

Capsaicin Analogue Supplementation Does Not Improve 10 km Running Time-Trial Performance in Male Amateur Athletes: A Randomized, Crossover, Double-Blind and Placebo-Controlled Study

Background: To investigate the acute effects of a capsaicin analogue supplement on 10 km time-trial performance and physiological responses in amateur athletes. Methods: Twenty-one participants (age = 29.3 ± 5.5 years, weight 74.2 ± 11.3 kg, height 176.0 ± 0.0 cm, fat mass 12.7 ± 3.8%, V˙O_2max 62.7 ± 8.4 mL·k⁻¹·min⁻¹), completed two randomized, double-blind trials: capsaicin analogue condition (Capsiate (CAP) = 24 mg) or a placebo (PLA) condition. The participants consumed two doses of 12 mg of CAP or PLA capsule 45 min before and immediately at the start of each trial. The time required to complete 10 km, lactate concentration, maximum heart rate (HR_peak), and rating of perceived exertion (RPE) were recorded. Results: The 10 km time-trial performance (CAP = 45.07 ± 6.41 min vs. PLA = 45.13 ± 6.73, p = 0.828) was not statistically significantly different between conditions. No statistically significant differences between conditions were detected for lactate concentration (p = 0.507), HR_peak (p = 0.897) and RPE (p = 0.517). Conclusion: Two doses of a 12 mg Capsaicin analogue supplement did not improve performance and physiological responses in a 10 km running time-trial in amateur athletes.

Capsaicin Supplementation during High-intensity Continuous Exercise: A Double-blind Study

To investigate the effect of acute capsaicin (CAP) supplementation on time to exhaustion, physiological responses and energy systems contribution during continuous high-intensity exercise session in runners. Fifteen recreationally-trained runners completed two randomized, double-blind continuous high-intensity exercises at the speed eliciting 90% V̇O_2peak (90% s V̇O_2peak), 45 minutes after consuming capsaicin or an isocaloric placebo. Time to exhaustion, blood lactate concentration, oxygen consumption during and 20-min post-exercise, energy systems contribution, time to reach V̇O_2peak, heart rate and the rate of perceived exertion (RPE) were evaluated. There was no significant difference between conditions for time to reach V̇O_2peak (CAP:391.71±221.8 vs. PLA:298.20±174.5 sec, ES:0.58, p=0.872), peak lactate (CAP:7.98±2.11 vs. PLA:8.58±2.15 µmol, ES:-0.28, p=0.257), time to exhaustion (CAP:654.28±195.44 vs. PLA:709.20±208.44 sec, ES:-0.28, p=0.462, end-of-exercise heart rate (CAP:177.6±14.9 vs. PLA:177.5±17.9 bpm, ES:-0.10, p=0.979) and end-of-exercise RPE (CAP: 19±0.8 vs. PLA: 18±2.4, ES: 0.89, p=0.623). In conclusion, acute CAP supplementation did not increase time to exhaustion during high-intensity continuous exercise nor alter physiological responses in runners.

Repeated Menthol Mouth Swilling Affects Neither Strength nor Power Performance

This study aimed to assess the effects of repeated menthol mouth swilling upon strength and power performance. Nineteen (10 male) participants completed familiarisation and experimental trials of repeated menthol mouth swilling (0.1% concentration) or control (no swill) in a randomised crossover design. Participants performed an isometric mid-thigh pull (IMTP; peak and mean force; N), vertical jump (peak; cm) and six second sprint (peak and mean power; W) under each condition. Participants completed three efforts per exercise task interspersed with three-minute recoveries. Mean best values were analysed via a two-way mixed repeated measures ANOVA, and differences reported as effect sizes ± 95% confidence intervals, with accompanying descriptors and p values. Differences in peak IMTP values were unclear between familiarisation and experimental trials, and between menthol and control conditions. Mean IMTP force differed between familiarisation and control (0.51; -0.15 to 1.14; p = 0.001) and familiarisation and menthol conditions (0.50; -0.15 to 1.14; p = 0.002) by a small degree, but were unclear between control and menthol conditions. Unclear differences were also noted on vertical jump performance compared to familiarisation and between experimental conditions, with repeated six second peak and average power performance also showing unclear effects across all comparisons. We conclude that repeated menthol mouth swilling does not improve strength or power performance.

Acute Capsaicin Supplementation Improved Resistance Exercise Performance Performed After a High-Intensity Intermittent Running in Resistance-Trained Men

de Freitas, MC, Cholewa, JM, Panissa, VLG, Toloi, GG, Netto, HC, Zanini de Freitas, C, Freire, RV, Lira, FS, and Rossi, FE. Acute capsaicin supplementation improved resistance exercise performance performed after a high-intensity intermittent running in resistance-trained men. J Strength Cond Res XX(X): 000-000, 2019-We sought to investigate the acute effects of capsaicin supplementation on the rate of perceived exertion (RPE) and heart rate during high-intensity intermittent exercise (HIIE) and resistance exercise performance executed after HIIE in resistance-trained men. Eleven resistance-trained men completed 2 randomized, double-blind trials: capsaicin condition or a placebo condition. The concurrent exercise session was composed of a 5-km intermittent run (1:1 effort and passive recovery ratio) and subsequent resistance exercise (4 × 70% of 1RM until muscle failure in the half-squat exercise). Heart rate was recorded during HIIE and after the protocol RPE (0-10 scale) was accessed. The resistance exercise performance was analyzed by the maximum number of repetitions performed for each set and the total volume (repetitions × weight lifted). During HIIE, the RPE (capsaicin = 7 ± 1 vs. placebo = 8 ± 1 points, t = -3.674, p = 0.005) and mean heart rate (capsaicin = 153 ± 13 vs. placebo = 158 ± 12 bpm, t = -2.292, p = 0.048) were significantly lower in the capsaicin compared with placebo condition. For subsequent resistance exercise, there was a significant decrease in volume across time (F = 19.889, p < 0.001, η = 0.69) with maximal number of repetitions performed in capsaicin than placebo condition (2,077.6 ± 465.2 kg vs. 1,838.9 ± 624.1 kg, p = 0.028, d = 0.43), but the condition vs. set was not significant (F = 0.582, p = 0.632, η = 0.06). Acute capsaicin supplementation induced a lower mean heart rate and RPE during HIIE and improved subsequent resistance exercise performance in resistance-trained men.

Herbal medicine for sports: a review

The use of herbal medicinal products and supplements has increased during last decades. At present, some herbs are used to enhance muscle strength and body mass. Emergent evidence suggests that the health benefits from plants are attributed to their bioactive compounds such as Polyphenols, Terpenoids, and Alkaloids which have several physiological effects on the human body. At times, manufacturers launch numerous products with banned ingredient inside with inappropriate amounts or fake supplement inducing harmful side effect. Unfortunately up to date, there is no guarantee that herbal supplements are safe for anyone to use and it has not helped to clear the confusion surrounding the herbal use in sport field especially. Hence, the purpose of this review is to provide guidance on the efficacy and side effect of most used plants in sport. We have identified plants according to the following categories: Ginseng, alkaloids, and other purported herbal ergogenics such as Tribulus Terrestris, Cordyceps Sinensis. We found that most herbal supplement effects are likely due to activation of the central nervous system via stimulation of catecholamines. Ginseng was used as an endurance performance enhancer, while alkaloids supplementation resulted in improvements in sprint and cycling intense exercises. Despite it is prohibited, small amount of ephedrine was usually used in combination with caffeine to enhance muscle strength in trained individuals. Some other alkaloids such as green tea extracts have been used to improve body mass and composition in athletes. Other herb (i.e. Rhodiola, Astragalus) help relieve muscle and joint pain, but results about their effects on exercise performance are missing.