Abstract: | Van Etten, Ludo M. L. A., Klaas R. Westerterp, Frans T. J. Verstappen, Bart J. B. Boon, and Wim H. M. Saris. Effect of an18-wk weight-training program on energy expenditure and physicalactivity. J. Appl. Physiol. 82(1):298-304, 1997.The purpose of this study was to examine theeffect of an 18-wk weight-training program on average daily metabolicrate (ADMR). Before the intervention and in weeks8 and 18 (T0,T8, andT18, respectively) data on bodycomposition, sleeping metabolic rate (SMR), food intake, energy cost ofthe weight-training program(EEex), and nontraining physicalactivity (accelerometer) were collected in the exercise group (EXER,n = 18 males). ADMR was determined ina subgroup (EX12, n = 12) by usingdoubly labeled water. At T0 andT18, data (except ADMR) were alsocollected in a control group (Con, n = 8). Body mass did not change in EXER or Con. Fat-free mass increased only in EXER with 2.1 ± 1.2 kg, whereas fat mass decreased in EXERas well as Con (2.0 ± 1.8 and 1.4 ± 1.0 kg, respectively). Initial ADMR (12.4 ± 1.2 MJ/day) increased atT8 (13.5 ± 1.3 MJ/day, P < 0.001) with no further increaseat T18 (13.5 ± 1.9 MJ/day). SMR did not change in EXER (4.8 ± 0.5, 4.9 ± 0.5, 4.8 ± 0.5 kJ/min) or Con (4.7 ± 0.4, 4.8 ± 0.4 kJ/min). Energy intake didnot change in EXER (10.1 ± 1.8, 9.7 ± 1.8, 9.2 ± 1.9 MJ/day) or Con (10.2 ± 2.6, 9.4 ± 1.8, 10.1 ± 1.5 MJ/day)and was systematically underreported in EX12 (21 ± 14, 28 ± 18, 34 ± 14%,P < 0.001).EEex (0.47 ± 0.20, 0.50 ± 0.18 MJ/day) could only explain 40% of the increase in ADMR.Nontraining physical activity did not change in both groups. Inconclusion, although of modest energy cost, weight-training induces asignificant increase in ADMR. |