Today is Christmas, and many of us are no doubt feeling a stretch on our waistlines after indulging a little (or a lot) in holiday treats. Though it may feel a little early to start thinking about those New Year's resolutions, a new study may offer some sage advice: compared with aerobic activities, daily weight training is more effective in keeping abdominal fat at bay.
The first thing many people do when they enter the gym at the beginning of January is to step on a treadmill, but the new study - published in the journal Obesity - suggests we may want to veer toward the weights section.
The Centers for Disease Control and Prevention (CDC) note that a wide variety of factors play a role in obesity, making it a "complex health issue to address."
However, because behavior and environment play a large role in obesity, the CDC note that these are the greatest areas for prevention and treatment.
Lead study author Rania Mekary, from the Department of Nutrition at Harvard School of Public Health (HSPH), speaks of the importance of a healthy waist circumference:
"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. Measuring waist circumferences is a better indicator of healthy body composition among older adults."
Because previous studies have focused on a specific population of participants - for example, those who were overweight or had type 2 diabetes - for short amounts of time, yielding mixed results, Mekary and her team used a large sample of healthy men, with a wide range of body mass indexes (BMIs), over a long period of time.
Weight training combined with aerobic exercise still the best option
The researchers studied 10,500 healthy men in the US over the age of 40 who were part of the Health Professionals Follow-up Study between 1996-2008. After assessing the physical activity, waist circumference and body weight of the men, the team analyzed changes in their activity levels during the 12-year period and how this affected their waistlines.
- An adult who has a BMI of 30 or higher is considered obese
- Waist circumference predicts risk for obesity-related diseases
- Obese individuals are at risk for several conditions, including type 2 diabetes, heart disease, cancers and hypertension.
Results showed that the men who increased the amount of time they spent lifting weights by 20 minutes a day had a smaller waistline gain during the time period (-0.67 cm), compared with those who increased their aerobic exercise by 20 minutes a day (-0.33 cm) or who increased yard work or stair climbing (-0.16 cm).
Not surprisingly, those who increased sedentary behaviors including watching TV gained more weight in their belly area.
The researchers also note that, although aerobic exercise by itself was linked to less weight gain compared with weight training, waist circumference is a better sign of health in older people. Additionally, combining weight training and aerobic activity yielded the best results, they say.
"Engaging in resistance training or, ideally, combining it with aerobic exercise could help older adults lessen abdominal fat while increasing or preserving muscle mass," adds Mekary.
Prof. Frank Hu, senior author from HSPH, says:
"This study underscores the importance of weight training in reducing abdominal obesity, especially among the elderly. To maintain a healthy weight and waistline, it is critical to incorporate weight training with aerobic exercise."
Earlier this week, Medical News Today reported on a study that suggested Americans are buying fewer cakes, cookies and pies - a positive trend that could help lower intake of energy, sugar and saturated fat.