Why We Lose Muscle Mass as We Age

Senior RunnerI figured that would get your attention. Who wants to lose muscle mass and strength? And let's face it, everything seems to get that much harder as we age. A new article from the Journal of Clinical Nutrition, September 2009, researched WHY we lose muscle size and strength as we age. They found that it has to do with how our muscles respond to insulin. Insulin drives amino acids which are the building blocks of protein into our muscles. They studied the muscle's response to insulin in 25 year olds and 60 year olds. Muscles responded to insulin much more effectively in the 25 year olds than the 60 year olds, thus concluding that age prevents muscles from responding to insulin and therefore, prevents the muscles from taking in more amino acids to build muscle. They had another finding: Three exercise sessions a week for over 20 weeks increased blood flow to the legs in the older subjects, reversing muscle wasting. We all know that eating a high carbohydrate rich meal will raise our insulin levels in our blood. However, our muscles are much more sensitive to insulin during a workout and within a half hour after exercise. An article in the Journal of Applied Physiology in May, 2009 found that eating a high carbohydrate, high protein meal within half an hour after exercise raises insulin levels in the blood and increases amino acid absorption into muscle. We can apply these findings to all ages. We should exercise at least three times a week and eat a high protein high carbohydrate meal within a half hour of exercise to maintain muscle mass and strength.