Capsaicinoid and Capsinoids as an Ergogenic Aid: A Systematic Review and the Potential Mechanisms Involved.

CONTEXT: Capsaicinoids and capsinoids (CAP) are natural substances found primarily in chili peppers and other spicy foods that agonize the transient receptor potential vanilloid-1 in the mouth, stomach, and small intestine. Several studies have shown CAP to be a potential antiobesity agent and to exhibit an analgesic effect in both rodents and humans. However, there is no scientific consensus about the effects of CAP on physical exercise performance and its physiological mechanisms of action. PURPOSE: This systematic review aimed to better elucidate the effects of CAP compounds as ergogenic aids and to discuss underlying mechanisms of action by which this supplement may potentially enhance endurance performance and muscular strength. CONCLUSIONS: Among 22 studies included in the review, 14 examined the effects of capsaicinoid or capsinoid compounds on endurance and resistance exercise performance in animals, with 9 studies showing benefits on performance. In humans, 8 studies were included: 3 demonstrated significant acute endurance benefits and 2 showed acute resistance exercise performance benefits compared with a placebo condition. Therefore, while more mechanistic studies are necessary to confirm these outcomes in humans, the available scientific literature appears to suggest that these compounds could be considered an effective nutritional strategy to improve exercise performance.

Acute Capsaicin Analog Supplementation Improves 400 M and 3000 M Running Time-Trial Performance.

OBJECTIVES: Performance in running-based sport depends on the ability to perform repetitive high intensity muscle contractions. Previous studies have shown that capsaicin analog (CAP) (i.e. Capsiate) supplementation may improve this performance. The purpose of this study was to investigate the acute effect of CAP supplementation on short (400 m) and middle distance (3000 m) running time-trial performance, maximum heart rate (HR), and rate of perceived exertion (RPE). METHODS: Twelve physically active men completed four randomized, double-blind trials: CAP condition (12 mg) or a placebo condition. Forty-five minutes after supplementation, the participants performed a 400- or 3000-meter running time trial. Time (in seconds) was recorded. HR was analyzed at rest and immediately post-exercise, and RPE was collected immediately after exercise. RESULTS: For both the 400 m time-trial (CAP = 66.4 + 4.2 sec vs Placebo = 67.1 + 4.8 sec, p = 0.046) and the 3000 m time-trial (CAP = 893.9 ± 46.8 sec vs Placebo = 915.2 ± 67.6 sec, p = 0.015), the time in seconds was significantly less in the CAP compared to placebo conditions. There were no statistically significant differences for HR and RPE in any condition. CONCLUSION: In summary, acute CAP supplementation improved 400 m and 3000 m running time-trial performance in a distance-dependent way but without modifying the HR and RPE.

A Single Dose of Oral ATP Supplementation Improves Performance and Physiological Response During Lower Body Resistance Exercise in Recreational Resistance-Trained Males.

Freitas, MC, Cholewa, JM, Gerosa-Neto, J, Gonçalves, DC, Caperuto, EC, Lira, FS, and Rossi, FE. A single dose of oral ATP supplementation improves performance and physiological response during lower body resistance exercise in recreational resistance-trained males. J Strength Cond Res 33(12): 3345-3352, 2019-The aim of this study was to investigate the acute effect of adenosine-5'-triphosphate (ATP) supplementation on performance and physiological responses during resistance exercise in recreationally resistance-trained males. Eleven men (age = 27.5 ± 5.5 years, mass = 83.4 ± 9.8 kg, height = 182 ± 0.04 cm) completed 2 randomized, double-blind trials: ATP supplement condition (ATP = 400 mg) or a placebo condition. Thirty minutes after supplement consumption, subjects performed 4 sets of half-squats until momentary muscular failure at 80% of the 1 repetition maximum with 2 minutes of recovery between sets. The total number of repetitions, blood pressure, heart rate, blood lactate, and oxygen consumption were evaluated. The total weight lifted were higher for the ATP condition compared with placebo (Placebo = 3,995.7 ± 1,137.8, ATP = 4,967.4 ± 1,497.9 kg; p = 0.005). Heart rate was higher at set-4 for ATP compared with placebo (p < 0.001) and oxygen consumption during exercise was greater for ATP (p = 0.021). There were no differences between conditions for lactate and blood pressure. In summary, a single oral dose of ATP supplementation improved lower-body resistance training performance and energy expenditure in recreational resistance-trained males.

Beta-Alanine Supplementation Improved 10-km Running Time Trial in Physically Active Adults.

The purpose of this study was to investigate the effects of ß-alanine supplementation on a 10 km running time trial and lactate concentration in physically active adults. Sixteen healthy subjects were divided randomly into two groups: ß-alanine (n = 8) and placebo group (n = 8). The experimental group ingested 5 g/day of ß-alanine plus 1 g of resistant starch, and control group ingested 6 g of resistant starch, both for 23 days. Time to complete a 10-km running time trial and lactate concentration following the test were assessed at baseline and post 23 days. The running training program was performed three times per week on non-consecutive days (day 1: running 7 km; day 2: six sprints of 500 m at maximum speed with 2 min of recovery; day 3: running 12 km). The time to complete a 10-km running time trial decreased significantly only for the ß-alanine group (Pre = 3441 ± 326.7, Post = 3209 ± 270.5 s, p < 0.05). When analyzing the delta (Time post minus Time at baseline value) there was a statistically significant difference between the ß-alanine vs placebo group (-168.8 ± 156.6 vs. -53.60 ± 78.81 s, p = 0.007), respectively. In addition, the ß-alanine group presented lower blood lactate concentration after the 10-km test (ß-alanine: Pre = 8.45 ± 1.94 vs. Post = 6.95 ± 2.44 mmol/L; Placebo: Pre = 8.7 ± 3.0 vs. Post = 10.8 ± 2.5 mmol/L, p = 0.03). In conclusion, ß-alanine supplementation improved the 10-km running time trial and reduced lactate concentration in physically active adults.