Article from JAMA March 23, 2010 posted on line and in the LA Times
11:07 24.03.2010Study involving over 34,000 women recommends that women work out 60 minutes a day to maintain a normal weight over a lifetime. This means working out every day for 1 hour not 1 hour a week.
This also refers to women who start out at normal weight. The issue of course is how much exercise is required to maintain a normal weight as some experts say an average of 35 minutes a day, seven days a week is probably sufficient. This again only refers to women who started out with a normal weight and exercise 1 hour a day to maintain their normal weight. This article refers to exercise for weight control, Moderate type of exercise was the exercise referred to in this study,and it talked about walking or hiking, jogging, running, biking, aerobic exercise or dance, use of exercise machines, yoga, tennis, squash, requetball and swimming. Housework and gardening were not included in the analysis. Of note is the fact that men have consistently shown in studies they require less exercise to maintain body weight.
Of course there are some problems with this study. Women who decide to be physically active may also decide to eat healthier and do other things to maintain a normal body weight, like sleep less. This study is really about energy balance. It takes a very small imbalance to gain a significant amount of weight over many years. One thing that is certain, all disease prevention starts out with exercise and diet.
