Weight training appears key to controlling belly fat




Weight training appears key to controlling belly fat


Healthy men who did twenty minutes of daily weight training had
less of an increase in age-related abdominal fat compared with men who spent
the same amount of time doing aerobic activities, according to a new study by
Harvard School of Public Health (HSPH) researchers and colleagues. Combining
weight training and aerobic activity led to the most optimal results. Aerobic
exercise by itself was associated with less weight gain compared with weight


The study appears online December 22, 2014 in Obesity.


“Because aging is associated with sarcopenia, the loss of
skeletal muscle mass, relying on body weight alone is insufficient for the
study of healthy aging,” said lead author Rania Mekary, a researcher in
HSPH’s Department of Nutrition. “Measuring waist circumference is a better
indicator of healthy body composition among older adults. Engaging in
resistance training or, ideally, combining it with aerobic exercise could help
older adults lessen abdominal fat while increasing or preserving muscle

Prior studies had been focused on a specific population (e.g.
overweight or with type 2 diabetes) and were of short duration and had mixed
results. The new study was long-term with a large sample of healthy men with a
wide range of BMI (body mass index).

Mekary and colleagues studied the physical activity, waist
circumference (in centimeters (cm)), and body weight of 10,500 healthy U.S. men
aged 40 and over participating in the Health Professionals Follow-up Study
between 1996 and 2008. Their analysis included a comparison of changes in
participants’ activity levels over the 12-year period to see which activities
had the most effect on the men’s waistlines. Those who increased the amount of
time spent in weight training by 20 minutes a day had less gain in their
waistline (-0.67 cm) compared with men who similarly increased the amount of
time they spent on moderate-to-vigorous aerobic exercise (-0.33 cm), and yard
work or stair climbing (-0.16 cm). Those who increased their sedentary
behaviors, such as TV watching, had a larger gain in their waistline.

“This study underscores the importance of weight training
in reducing abdominal obesity, especially among the elderly,” said Frank
Hu, professor of nutrition and epidemiology at HSPH and senior author of the
study. “To maintain a healthy weight and waistline, it is critical to
incorporate weight training with aerobic exercise.”