EFFECTS OF PYRUVATE SUPPLEMENTATION DURING TRAINING ON BODY COMPOSITION& METABOLIC RESPONSES TO EXERCISE

Abstract

347 Pyruvate supplementation has been reported to promote fat loss in sedentary obese individuals possibly by altering carbohydrate and/or fat metabolism. This study examined the effects of pyruvate supplementation on body composition and metabolic responses to exercise in moderately overweight women initiating training. 23 females (33±2 yrs, 71.5±2 kg, 27.4±0.7 BMI, 34.9±1% body fat) were matched/paired and assigned to ingest two times per day for 30 days in a double-blind and randomized manner either a placebo (PL) containing 2.5 g calcium carbonate, 4 g maltodextrin, and 1 g dextrose or 5 g/d of calcium pyruvate (PYR). During this time, subjects participated in a supervised walking (30 min, 3 times per week at 70% of VO2max) and resistance-training program (2 sets of 8-12 repetitions, 8 machines, 3 times per week). Prior to and following supplementation, subjects: recorded food intake for 4-d; had body composition determined via hydrodensiometry; performed a maximal cardiopulmonary exercise test; and, performed a 45-min walk test at 70% of pre-training VO2max in which pre- and post-exercise blood samples were obtained. Data were analyzed by repeated measures ANOVA and are presented as mean±SEM changes from pre-supplementation values. No significant differences were observed between groups in energy intake or training volume although energy intake in the PYR group was slightly suppressed (PL -1.9±1, PYR-5.1±3 kcal·kg-1, p=0.30). Significant interactions were observed in changes in body mass (PL 1.21±0.3, PYR 0.32±0.3 kg, p=0.04) and fat mass (PL 1.11±0.5, PYR -0.41±0.5 kg, p=0.03) with no differences observed in lean mass (PL 0.09±0.5, PYR 0.73±0.3 kg, p=0.29) or percent body fat (PL 1.0±0.7, PYR-0.7±0.6%, p=0.07). No significant differences were observed between groups in changes in maximal exercise responses. During the walk test, no significant differences were observed in exercise VO2, non-esterified fatty acids, glycerol, or β-hydroxybutyric acid levels. RER values tended to be higher in the PYR group (PL -0.018±0.01, PYR 0.015±0.01, p=0.10). Results indicate that PYR supplementation during training may modestly affect body composition, has no effect on maximal exercise responses, and does not markedly affect substrate utilization during exercise.