Relationships of aerobic capacity and percent body fat with plasma free fatty acid following walking.

We investigated relationships of peak VO2 and percent body fat with postexercise plasma free fatty acid (FFA) and glycerol concentrations in 14 men using multiple-regression techniques. During 1 h of walking (36% of peak VO2), no significant differences in plasma-FFA response were attributed to either peak VO2 or percent body fat. However, individuals with higher peak VO2S tended to have greater elevations in plasma-glycerol concentration during exercise (p = 0.074). They also had greater peak FFA concentrations and FFA X glycerol(-1)-molar ratios immediately after exercise and faster subsequent clearing of excess FFA from the blood (p less than 0.05). Percent fat was not related to postexercise plasma glycerol, FFA, FFA X glycerol-1 responses. Differing postexercise FFA responses, as related to peak VO2, were due, not to varying rates of lipolysis but rather to different rates of FFA mobilization and utilization.