Effects of Mixed Isoenergetic Meals on Fat and Carbohydrate Metabolism during Exercise in Older Men

The present study was designed to investigate the effects of four different meals on fat and CHO metabolism during subsequent exercise in elderly males. Eight healthy males (age: 63.3 ± 5.2 years) reported to the physiology laboratory on four separate occasions, each of which was allocated for the performance of a 30-minute exercise on a cycle ergometer at 60% V̇O2max⁡ after having normal (N), high fat (HF), high carbohydrate high glycaemic index (HGI) and high carbohydrate low glycaemic index (LGI) meals. Fat oxidation during exercise after the meals (HF=0.26±0.04 g/min; N=0.21±0.04 g/min; HGI=0.22±0.03 g/min; LGI=0.19±0.03 g/min) was not significant (P>.05), and neither were the rates of carbohydrate oxidation (N=1.79±0.28, HF=1.58±0.22, HGI=1.68±0.22, and LGI=1.77±0.21 g/m). NEFA concentration increased after HF (P