Alterations of autonomic nervous activity and energy metabolism by capsaicin ingestion during aerobic exercise in healthy men

• Published in: Journal of Nutritional Science and Vitaminology 2007, Vol.53(2), pp.124-132
• Main Authors: Shin, K.O.(Kyoto Univ. (Japan)), Moritani, T
• Format: Article
• Language: English
• Subjects: ACTIVIDAD FISICA; ACTIVITE PHYSIQUE; Adult; AEROBIOSE; AEROBIOSIS; Analgesics, Non-Narcotic - administration & dosage; Analgesics, Non-Narcotic - pharmacology; AUTONOMIC NERVOUS SYSTEM; Autonomic Nervous System - drug effects; Autonomic Nervous System - physiology; Biological and medical sciences; CAPSAICIN; Capsaicin - administration & dosage; Capsaicin - pharmacology; capsaicin tablet; CAPSAICINA; CAPSAICINE; cardiac depolarization-repolarization interval; ECHANGE GAZEUX; Electrocardiography - drug effects; ENERGY METABOLISM; Energy Metabolism - physiology; Exercise - physiology; Exercise Test - drug effects; Exercise Test - methods; Feeding. Feeding behavior; FOOD INTAKE; Fundamental and applied biological sciences. Psychology; GAS EXCHANGE; GENERO HUMANO; GENRE HUMAIN; Heart Rate - drug effects; heart rate variability power spectral analysis; Humans; INGESTION DE ALIMENTOS; INTERCAMBIO DE GASES; Male; MANKIND; METABOLISME ENERGETIQUE; METABOLISMO ENERGETICO; OXIDACION; OXIDATION; OXYDATION; PHYSICAL ACTIVITY; PRISE ALIMENTAIRE (HOMME); Reference Values; RESPIRACION; RESPIRATION; Rest - physiology; SISTEMA NERVIOSO AUTONOMO; SYSTEME NERVEUX AUTONOME; Thermogenesis - drug effects; Time Factors; Vertebrates: anatomy and physiology, studies on body, several organs or systems
• ISSN: 0301-4800; 1881-7742
• DOI: 10.3177/jnsv.53.124

We investigated whether capsaicin ingestion (150 mg) enhances substrate oxidation associated with thermogenic sympathetic activity as an energy metabolic modulator without causing prolongation of the cardiac QT interval during aerobic exercise in humans. Ten healthy males [24.4 (4.3) y] volunteered for this study. The cardiac autonomic nervous activities evaluated by means of heart rate variability of power spectral analysis, energy metabolism, and ECG QT interval were continuously measured during 5-min rest and 30-min exercise at 50% of maximal ventilatory threshold (50%VTmax) on a stationary ergometer with placebo or capsaicin oral administration chosen at random. The results indicated that there were no significant differences in heart rate during rest or exercise between the two trials. Autonomic nervous activity increased in the capsaicin tablet trial during exercise, but the difference did not reach statistical significance. Capsaicin, however, significantly induced a lower respiratory gas exchange ratio [0.92 (0.02) vs. 0.94 (0.02), means (SE), p0.05] and higher fat oxidation [0.17 (0.04) vs. 0.12 (0.04) g/min, means (SE), p0.05] during exercise. On the other hand, the data on the cardiac QT interval showed no significant difference, indicating that oral administration of capsaicin did not cause any adverse effect on cardiac depolarization-repolarization. In conclusion, it may be considered that capsaicin consumption 1 h before low intensity exercise (50%VTmax) is a valuable supplement for the treatment of individuals with hyperlipidemia and/or obesity because it improves lipolysis without any adverse effects on the cardiac depolarization and repolarization process.