Information sourced from NEJM Journal Watch:
Exercise Training Two Times Weekly Improves Fitness as Much as More Frequent Exercise in Older Women
Paul S. Mueller, MD, MPH, FACP reviewing Hunter GR et al. Med Sci Sports Exerc 2013 Jul.
But four times weekly provided the most benefit.
Aerobic exercise and resistance training can mitigate age-related decline in physical performance, and it seems intuitive that daily exercise is more beneficial than less frequent exercise. However, optimal frequency of exercise in older adults is unclear. In this randomized trial, investigators examined the effects of three different combined aerobic and resistance training programs on total energy expenditure and activity-related energy expenditure (AEE) in 72 older sedentary women (age range, 60 74).
Participants were randomized to weekly schedules of 1 day of aerobic and 1 day of resistance training (1+1), 2 days of aerobic and 2 days of resistance training (2+2), or 3 days of aerobic and 3 days of resistance training (3+3). Aerobic training involved 40 minutes on a treadmill or cycle ergometer at 80% maximum heart rate; during resistance training, participants performed two sets of 10 repetitions of 10 different exercises. At 16 weeks, aerobic fitness, strength, and fat-free mass improved similarly in all three groups, but total and activity-related energy expenditure increased significantly (by about 300 kcal daily) only in the 2+2 group. AEE not related to the scheduled exercise sessions increased significantly in the 2+2 group (by 200 kcal daily), did not change significantly in the 1+1 group, and decreased significantly in the 3+3 group (by 150 kcal daily).
In this trial, 2 days of exercise training weekly improved aerobic fitness, strength, and fat-free mass as much as more frequent exercise. However, 4 days weekly resulted in the most energy expenditure. Paradoxically, the women who exercised 6 days weekly experienced a decrease in AEE not related to their exercise training. The authors note that women in this group complained of the large time commitment their training program required and speculate that these women, as a result, cut back on their free-time physical activities. Whether these findings apply to women of other ages or to men is unknown.
Hunter GR et al. Combined aerobic and strength training and energy expenditure in older women. Med Sci Sports Exerc 2013 Jul; 45:1386. [PubMed ® abstract]
NEJM Journal Watch is produced by NEJM Group, a division of the Massachusetts Medical Society.Copyright ©2013 Massachusetts Medical Society. All rights reserved.
The above message comes from NEJM Journal Watch, who is solely responsible for its content.
You have received this email because you requested follow-up information to an Epocrates DocAlert ® Message. For more information about DocAlert ® Messages, please click here.