Efficiency of a Free-Living Physical Activity Promotion Program Following Diet Modification for Fat Loss in Japanese Obese Men

Abstract

The aim of the current study was to examine the efficiency of a free-living physical activity promotion (PAP) program following a diet modification program for fat loss. Fifty obese men, aged 51.4±7.0 y, received a 6-mo regimen consisting of 2 phases. Weekly 90-min free-living PAP sessions were provided for 3 mo immediately after a 3-mo diet modification phase. Fat mass (FM) was measured at baseline and at months 3 and 6 using dual energy X-ray absorptiometry. The time spent in moderate-vigorous physical activity (MVPA) was monitored by a validated single-axis accelerometer. The total energy intake of all participants was assessed at baseline and during weeks 9 and 10 of both the diet modification and PAP programs. The change (Δ) in FM was -1.4±1.9 kg (p<0.05) during the PAP program after the diet modification program (-4.3±2.9 kg, p<0.01). Although there was no significant relationship between ΔFM and ΔMVPA during the PAP phase (p=0.11), MVPA was significantly increased during the PAP phase (+76.0±146.5 min/wk, p<0.01). However, a significant correlation was observed between energy intake/weight and MVPA during the PAP program (r=0.39). Our results suggest that the magnitude of expected FM loss induced by an increase in PA may be suppressed as a result of increased energy intake, even during a PAP program after a diet modification program.