Can a Man Over 45 Still Gain Muscle Size?

Senior men training in a gym.
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Middle age brings with it many physical changes that are not always welcome. In particular, a loss of strength and muscle size can leave you feeling weaker and less vital than you did in your younger days. But regular resistance training done at a challenging intensity can help you slow the rate and reverse the trend of muscle loss.

Mass Destruction

As humans age, we begin to lose our lean muscle mass, a condition called sarcopenia. According to a 2005 article by endocrinologist K.S. Nair, MD, PhD, published in the "American Journal of Clinical Nutrition," muscle loss associated with aging begins as early as the fourth decade, when you are in your 30s. By the time you are 80, you may have lost as much as 40 percent of your total muscle mass. Over time, loss of muscle can lead to frailty, disability and metabolic disorders.

Little Old You

A number of factors contribute to your shrinking physique as you age. On the microscopic level, decreases in mitochondrial DNA and messenger RNA cause a decrease in the turnover of muscle protein, leading to a decrease in muscle fiber cross-sectional area. A 2010 review published in "Interdisciplinary Topics in Gerontology" also points to reductions in growth hormone, insulin, estrogen and testosterone, along with inadequate nutrition, as underlying causes of muscle loss. The authors note that regular exercise performed early in life can slow the rate of loss.

Getting Sexy Back

Reversing the trend of muscle loss is a matter of lifestyle choices and training. A 2002 article published in "Physical Therapy" notes that appropriate exercise can slow and reverse some of the age-related changes in your lean muscle, including reduced muscle mass and decreased force production. According to Dr. Nair, both aerobic exercise and resistance training can effectively enhance the turnover of muscle protein associated with increases in muscle size and strength. A well-balanced diet with adequate protein will support the synthesis of muscle tissue.

Train to Gain

Applying the appropriate volume and intensity of exercise is important for gaining muscle size. Exercise scientist Len Kravitz, PhD of the University of New Mexico, recommends performing resistance training exercises three days per week for all your muscle groups, working your way up to three sets of eight to 10 repetitions for each exercise. Resistance should be set at 80 percent of 1RM, or one repetition maximum, which is the maximum amount of weight you can lift one time in a given exercise.