Are you a fan of spicy foods? You might be in luck. Research presented at Experimental Biology 2021 suggests a specific compound found in fiery foods such as chili peppers may have the ability to help you improve your exercise performance.
Capsaicin, the bioactive ingredient in chili peppers, stimulates our pain receptors. This stimulation has been shown to improve mitochondrial function, lower blood pressure, improve vascular function and reduce fatigue development in animals. However, researchers haven’t studied whether people might have these same effects.
This got Gaia Giuriato, a PhD candidate at the University of Verona in Italy, interested in studying the effects of chili peppers on exercise performance. Chili peppers are widely used in Italy. Giuriato knew that capsaicin had cardiovascular benefits and wondered if the same benefits might also extend to performance.
Giuriato and colleagues studied a small group of young men who took a supplement containing capsaicin or a placebo—a pill without active ingredients—before cycling to exhaustion at 85% maximum effort. Afterward, the researchers assessed muscle fatigue in the men’s quadriceps muscle.
Capsaicin didn’t seem to enhance endurance performance—the participants tired out in a similar amount of time no matter which supplement they took. Blood pressure, heart rate and cardiac output were also similar in the capsaicin and the control conditions. This suggests that capsaicin does not affect cardiovascular function during or after exercise.
However, capsaicin did reduce muscle tiredness. The men who took capsaicin had less reduction in muscle contractile properties—less fatigue—after exercise.
These results provide some evidence that capsaicin may prevent some of the decline in muscle performance after fatiguing exercise. Giuriato concludes that capsaicin may not have a central mechanism of action, but rather a peripheral or neuromuscular mechanism that may improve muscle performance. It could be that a single dose of capsaicin is not enough to produce a real change in humans. She thinks that it will be interesting to explore taking capsaicin supplements on a regular basis combined with exercise training.
If you enjoy chili peppers, keep on eating them. There is some evidence that they might be able to spice up your next workout.
Brady Holmer is a PhD student in exercise physiology at the University of Florida. His lab focuses on cardiovascular physiology, mainly how exercise can play a role in health, disease and aging. Holmer hosts a podcast called “Science & Chill,” where he sits down with scientists in the fields of physiology, biology, health and nutrition to discuss their work. He served as a meeting blogger for the American Physiological Society’s 2021 annual meeting at Experimental Biology.