Effect of self-selected and imposed-intensity walking programs on fat oxidation in obese women

The purpose of this study was to investigate the effect of a walking program at self-selected or an imposed intensity on maximal fat oxidation ([Fat.sub.max]) in obese women. The study included 12 obese female volunteers (mean age 44.3 [+ or -] 8.3 yrs) who were randomly divided into two groups: self-selected or imposed intensity. A test until exhaustion was performed to determine maximal oxygen uptake (V[O.sub.2] max), ventilatory threshold, and [Fat.sub.max] before and after intervention. The study duration was 12 wks with three exercise sessions per week on nonconsecutive days. There was no difference in [Fat.sub.max] between the groups in the pre-intervention test. Only the self-selected intensity group showed a significant increase in [Fat.sub.max] between the pre- and post-intervention testing. However, the V[O.sub.2] at [Fat.sub.max] was similar in both groups in the post-intervention test. Thus, while the self-selected training program induced changes in [Fat.sub.max], V[O.sub.2] at [Fat.sub.max] was similar in both groups. This latter finding suggests that the changes arising from the different training programs appear to be related more to the V[O.sub.2] at [Fat.sub.max] than the percentage of V[O.sub.2] max. Key Words: Aerobic Exercise, Obesity, Walking, [Fat.sub.max]