Author(s): CHENG, C., YANG, Y.R.2, WANG, H.J.1, LEE, S.M.1, LIN, C.Y.1, LIN, Y.D.1, Institution: NATIONAL TAIWAN NORMAL UNIVERSITY, Country: TAIWAN, Abstract-ID: 203

INTRODUCTION:
Capsaicin (CAP) has recently been identified as a modulator of the transient receptor potential vanilloid 1 channel, thereby promoting the release of calcium ions and acetylcholine, producing analgesic effects, and increasing fat oxidation, which may contribute to improved exercise performance. However, limited studies investigate the effects of CAP ingestion on exercise performance in athletes. The 3-min all-out exercise test (3MT) has been established as a reliable method to estimate critical power (CP) and the curvature constant for severe exercise (W′). This study aimed to investigate the acute effects of CAP supplementation on the 3MT performance in trained cyclists.
METHODS:
Twelve male cyclists (age, 19 ± 1 years; height, 173 ± 6 cm; body mass, 66 ± 7 kg; VO2max, 69 ± 8 ml·kg-1·min-1) participated in this randomized, double-blind, crossover study. The initial visit served as a familiarization session. During the second visit, participants completed an incremental cycling test to determine the appropriate resistance for the 3MT. Subsequently, participants underwent three treatments, including CAP (8 mg of capsaicin in capsules), PLA (placebo), and CON (control), before conducting the 3MT on a cycling ergometer to estimate the CP and W′. Throughout the 3MT, oxygen uptake (VO2), heart rate (HR), quadriceps muscle oxygenation were continuously monitored. Blood samples were collected before and 30-min after ingestion, and 5-min after 3MT to assess lactate (La) concentrations.
RESULTS:
No significant differences were found among treatments in CP (CAF vs. PLA vs. CON, 266 ± 42 vs. 266 ± 38 vs. 266 ± 42 W, p > 0.05), W′ (CAF vs. PLA vs. CON, 12.8 ± 3.2 vs. 13.2 ± 2.6 vs. 13.0 ± 3.7 kJ, p > 0.05), peak power, average power per 30-s interval, total work (CAF vs. PLA vs. CON, 60.5 ± 6.6 vs. 60.8 ± 6.8 vs. 60.6 ± 6.9 kJ, p > 0.05) and fatigue rate (CAF vs. PLA vs. CON, 33.3 ± 6.4 vs. 35.4 ± 7.8 vs. 36.0 ± 6.4 sec, p > 0.05) during 3MT. Similarly, no significant differences were detected in peak VO2 (CAF vs. PLA vs. CON, 4.39 ± 0.39 vs. 4.42 ± 0.55 vs. 4.43 ± 0.56 L·min-1, p > 0.05), peak HR, tissue saturation index (CAF vs. PLA vs. CON, 43.8 ± 7.7 vs. 45.3 ± 7.8 vs. 44.7 ± 7.2%, p > 0.05), total hemoglobin, and deoxyhemoglobin during 3MT. The La after 3MT also did not differ significantly among treatments (CAF vs. PLA vs. CON, 10.5 ± 3.7 vs. 11.8 ± 3.2 vs. 10.4 ± 2.8 mmol·L-1, p > 0.05).
CONCLUSION:
Capsaicin ingestion might not have ergogenic effects on the short-term high-intensity exercise performance, nor on CP and W′ in elite cyclists. Studies with larger sample sizes are needed to clarify the effects of capsaicin supplementation on both aerobic and anaerobic capacities in athletes. Supported by grants from National Science and Technology Council, Taiwan (NSTC 113-2410-H-003-152-MY2). Contact: andescheng@ntnu.edu.tw