March 13, 2013
Gary Hunter, PhD , a professor in School of Education  and a senior scientist in the Nutrition Obesity Research Center (NORC ) was noted for his publication, "Combined Aerobic/Strength Training and Energy Expenditure in Older Women" [PMID: 23377831 ], Medicine & Science in Sports & Exercise, in the New York Times blog post " Why Four Workouts a Week May Be Better Than Six  on February 13 , 2013. According to the study, a fairly leisurely approach to scheduling workouts may actually be more beneficial than working out almost daily.
Gary Hunter, Ph.D., and Gordon Fisher, Ph.D., of the UAB Department of Human Studies , were among a group of scientists who gathered 72 sedentary women, ages 60 to 74, and observed how they were affected by various frequencies of aerobic and resistance training. Older women were selected because they have more of a history of overtraining than younger women, and the researchers wanted to examine that.
The women were divided into groups of those who worked out two-, four- and six-times a week. For 16 weeks, they were monitored while they participated in 40-minute increments of training.
In the end, the women who worked out twice a week were just as aerobically fit and strong as the women who exercised six times a week. All but the six-times-a-week group burned post-workout calories.
The women who worked out four times a week burned nearly 225 additional calories each day outside of the gym, according to the study. The women who trained twice a week burned nearly 100 more calories in their non-workout mode. The six-times-a-week group, however, burned no significant amount of additional calories when they were not exercising.M/
Those who followed a less-rigorous exercise regimen were energized and strengthened to do more non-workout activities throughout the week. The women who followed the six-day schedule said they were tired and pressed for time, and they were therefore less active outside of the gym.
“Being physically active is important,” said Hunter. “Training two- to three-times a week might be enough. If we can find ways to increase our activities rather than training, it is very good.”
Although older women are thought to have a tendency to overtrain during workouts, none in the study did.
The takeaway, Hunter said, is that you do not have to spend all of your time training. But, when you do train, your body is better conditioned to manage life’s physical activities.
“In my mind, it is not so much the energy you burn in your exercise, but the improvement of ease and fitness that you gain that is very important,” Hunter said.