[[alternative]]Effect of short-term (-)-hydroxycitric acid supplementation on endurance exercise performance

[[abstract]]Purpose: To investigate the effect of short-term (-)-hydroxycitric acid (HCA) supplementation on endurance exercise performance. Methods: Seventeen healthy males volunteered to participate in this single blind study, and were randomly divided in two groups: H group (HCA, 2.5 g/day, n = 9, age: 21.7±2.4 yrs, height: 177.9±6.4 cm, weight: 67.4±5.9 kg) and P group (cellulose, 2.5 g/day, n = 8, age: 21.7±1.7 yrs, height: 173.3±4.2 cm, weight: 66.6±7.7 kg). Before and after a 5-day load of HCA or placebo, all subjects performed an incremental endurance exercise test. The incremental endurance exercise test included 10-min mild (40%VO2max) and 10-min heavy (80%VO2max) exercises and then the slope of treadmill was increased two degrees every three minutes till volitional exhaustion. Body composition was measured by bioelectrical impedance analyzer. Results: There was a significantly decreased body fat only in H group (p < .05), and the lean body mass and muscle mass were significantly increased in H group after supplementation (p < .05). The heart rate (HR), oxygen intake and blood lactate had no significant differences between the H and P groups (p > .05), however, in the H group, the respiratory exchange rate (RER) and carbohydrate (CHO) oxidation were significantly decreased, and the fat oxidation was significantly increased (p < .05) during mild endurance exercise. In addition, the exhausting time was significantly extended in the H group (p < .05). Conclusion: Short-term HCA supplementation could not affect HR, oxygen intake and blood lactate either on the mild or the heavy endurance exercise, however, the fat oxidation and time to exhaustion during the endurance exercise would be improved by HCA.