Effect of prolonged branched-chain amino acid supplementation on metabolicresponse to anaerobic exercise in standardbreds

This study investigated the effect of prolonged BCAA supplementation on met abolic response to a 1600m run on treadmill in Standardbred trotters. Four trained Standardbreds were divided into two groups and assigned in a 2x2 La tin square design. Both groups were fed and exercised similarly: one group received an oral amino acids supplement (12 g leucine, 9 g isoleucine and 9 g valine) 30 minutes prior to exercise and immediately after, the other gr oup received a placebo. The horses received the supplement 3 days per week for 5 weeks. In the last week horses performed an anaerobic exercise test o n an inclined (3.5%) high-speed treadmill. The exercise consisted of a 15 m inute warm-up phase immediately followed by a 1600 m run at maximal speed ( heart rate > 200 beats/min). Blood samples were collected pre-exercise, aft er exercise and during recovery (10 min, 30 min, and 24 h), and analyzed fo r lactate, ammonia, total protein, urea, uric acid, creatinine, free fatty acids (FFA), creatine kinase (CK), lactate dehydrogenase (LDH), aspartate a mino transferase (AST). Heart rate was continuously recorded during exercis e and recovery. No statistical differences between the groups were observed for all the considered parameters. Nevertheless, BCAA supplementation resu lted in a higher plasma ammonia and urea concentrations as reported in prev ious studies in humans and rats. These data suggest that a BCAA supplementa tion are not effective in enhancing performance in healthy and well-fed hor ses.