For every additional pound of muscle you gain, your body will burn about 50 more calories each day. A study by Wayne Westcott, Ph.D., from the South Shore YMCA in Quincy, Massachusetts, showed that a woman who strength trains two or three times a week for eight weeks gains 1.75 lbs of muscle and loses 3.5 lbs of fat.
And Johns Hopkins researchers found that while aerobic exercise burns more calories at the time you are exercising, your metabolism returns to normal about 30 minutes after you finish your workout. Individuals who perform strength training, however, elevate their metabolisms (burn more calories) for two hours after their workouts end.
4. Strength training increases bone density.
A study conducted by Miriam E. Nelson, Ph.D. of Tufts University found that strength training increases both muscle mass and bone density. Dr. Nelson’s research showed that women who lifted weights did not lose any bone density throughout the study, and actually gained an average of 1% more bone mass in the hip and spine. Non-exercising women lost 2% to 2.5% of bone mass during the same period of time.
Another University of Arizona study showed a 3% increase in spine and hip bone mineral density after an 18-month strength training program among women, ages 28 to 39.
5. Strength training counteracts depression.
In a study of 32 men and women who suffered from chronic depression, Nalin Singh, M.D. and Tufts University associates divided the individuals into two groups. They directed half to perform strength training while the other half received health information. After three months, 14 of the 16 members who lifted weights felt better and no longer met the criteria for depression.
A Harvard study also showed that 10 weeks of strength training reduced clinical depression symptoms more successfully than standard counseling alone.
6. Strength training reduces sleep difficulties.
Ten people in Dr. Singh’s strength training group (see reason 5, above) also reported sleep difficulties at the start of the study. After 12 weeks, six of the 10 reported they no longer had trouble sleeping—they fell asleep more quickly, slept more deeply, awakened less often and slept longer.
7. Strength training reduces your risk of diabetes.
Adult-onset (Type 2) diabetes is a growing problem, with over 14 million Americans suffering from the condition. Research shows that strength training can increase glucose utilization in the body by 23% in just four months. As muscles contract and relax during exercise, they use sugar for energy. To meet this energy need, your body uses sugar supplies in your blood, reducing your blood sugar levels.