Women Should Pump Iron to Manage Weight
In this secondary investigation, researchers set out to examine the effects of resistance training on soft tissue changes and weight management in postmenopausal women. Subjects included 122 females (mean age 56.3 years, give or take 4.3 years) who were previously sedentary. After the the first year of intervention, the control subjects were allowed to begin the prescribed exercise regimen, or in other words "crossover." This created 3 test groups: exercisers - those who were assigned to the exercise group at baseline (n=65); crossovers - those who crossed-over to the exercise program at one year (n=32); and true controls - those women who remained sedentary (n=25).
Exercisers and crossovers participated in 8 core resistance training activities for 2 sets of 8 repetitions each (at 70-80% 1-repetition maximum) on 3 nonconsecutive days/week. They also engaged in various stretching, balance, and progressive weight bearing activities (e.g., stair stepping with weighted vests). Exercise frequency and workloads of the various exercises were recorded. Body weight and fat were measured at baseline and annually for 6 years using anthropometry and dual-energy x-ray absorptiometry.
Researchers found that over the 6-year testing period, weight gain across the 3 testing populations occured in a "stepwise fashion." That is, individuals who remained sedentary gained the most weight (approximately 2.1 kg) while crossovers gained approximately 0.7 kg and exercisers gained the least at 0.4 kg on average. Women in the true control group significantly gained weight and total body fat between baseline and year 6.
The investigators conclude that participation in resistance training is a viable option for postmenopausal women to manage body weight. They purport that it should be one component of a regular comprehensive exercise program to improve overall health and prevent disease.
Medicine & Science in Sports & Exercise, July 2010, Vol. 42 Issue 7, pp. 1286-1295, "Resistance Training Predicts 6-yr Body Composition Change in Postmenopausal Women," Bea. J.W. et al.,.