A recent study shows that even fairly moderate regular activity helps maintain a healthy body weight.
Researchers examined the relationship between physical activity (PA) and weight maintenance/weight gain in a large group (46,754) of premenopausal women (aged 25 to 43 years old). Participants signed up for the study in 1989 and checked in again in 1997. 62% of the population gained more than 5% of their baseline weight by 1997.
One important difference between weight gainers and weight maintainers was physical activity. Women who exercised less than 30 min per day were much more likely to gain weight than women who exercised more than 30 min per day. This was true even for women whose only activity was walking, although the faster they walked, the better they did. Jogging/running was even better than walking for helping to maintain weight.
The more exercise women did, the more they were able to maintain their weight, but even small increases in activity (between 11 and 20 min daily) helped a lot, especially for folks who started out overweight in 1989.
Sedentary behavior independently predicted weight gain. Researchers’ conclusion:
“Sustained PA for at least 30 min per day, particularly if more intense, is associated with a reduction in long-term weight gain, and greater duration is associated with less weight gain. Sedentary women of any baseline weight who increase their PA will benefit, but overweight women appear to benefit the most.”
In other words, make it regular, make it consistent, and make it as intense as you can manage.
Mekary, R. A. et al. Physical activity patterns and prevention of weight gain in premenopausal women. International Journal of Obesity (2009) 33, 1039–1047; doi:10.1038/ijo.2009.127; published online 23 June 2009