The present study quantified changes in body composition (densitometry, 5 fatfolds, 12 girths) in 26 initially obese women (% fat, X ± SD = 36.9, 7.2) during a 14 week program of exercise and voluntary dietary restriction. Exercise consisted of thrice weekly workouts of calisthenics (15 min.) and walk-jog (30 min.) at approximately 60% of maximum intensity gauged by pulse rate. A computer-based nutrition plan that considered age, body size, and level of physical activity provided daily breakfast, lunch and dinner menus. The individualized programs were designed so body weight would become reduced by approximately 0.7 kg a week. Body composition was assessed at each 2.3 kg of weight loss. For the statistical analysis, subjects were grouped by total weight loss (2.3 kg, N = 9; 4.5 kg, N = 10; 9.1 kg, N = 7). The changes in body composition were most pronounced for the 9.1 kg group; their relative body fat decreased from 39.9% to 27.8% (11.7 kg fat loss). For the groups that reduced by 2.3 and 4.5 kg, relative body fat reduced by 3.8 (p<.05) and 1.5 (p>.05) % fat units, respectively. There was no significant loss of lean weight among the groups. When weight loss doubled from 2.3 to 4.5 kg, there was a corresponding two-fold decrease in most of the criterion fatfold and girth measures. When there was a further doubling of weight loss from 4.5 to 9.1 kg, changes in absolute fat weight, sum of 5 fatfolds, and 12 girths changed approximately three-fold. We conclude that proportional changes in body composition and surface anthropometry mirror changes in weight loss to 2.3 kgs; thereafter, the relative change in body composition becomes more pronounced and amounts to a three-fold decrease up to a 9.1 kg loss in weight.
King, Marjorie A. and Katch, Frank I.
"Changes in Body Density, Fatfolds and Girths at 2.3 Kg Increments of Weight Loss,"
5, Article 5.
Available at: https://digitalcommons.wayne.edu/humbiol/vol58/iss5/5