Abstract des Autors

This study investigated the effects of 12 weeks of aerobic exercise plus voluntary food restriction on the body composition, resting metabolic rate (RMR) and aerobic fitness of mildly obese middle-aged women. The subjects were randomly assigned to exercise/diet (n=17) or control (n=15) groups. The exercise/diet group participated in an aerobic training programme, 45-60 min/day at 50-60 of maximal oxygen uptake (VO2max), 3-4 days/week, and also adopted a self-regulated energy deficit relative to predicted energy requirements (-1.05 MJ/day to -1.14 MJ/day). After the regimen had been followed for 12 weeks, the body mass of the subjects had decreased by an average of 4.5 kg, due mainly to fat loss, with little change of fat free mass (mff). The absolute RMR did not change, but the experimental group showed significant increases in the RMR per unit of body mass (10) and the RMR per unit of mff (4). The increase in RMR/mff was not correlated with any increase in VO2max/mff. The resting heat production per unit of essential body mass increased by an average of 21, but the resting heat production rate per unit of fat tissue mass remained unchanged. We concluded that aerobic exercise enhances the effect of moderate dietary restriction by augmenting the metabolic activity of lean tissue.