There are some particular biological changes that happen as we age. If you compare the body of a  70 year old to when they were  25 years old, even though their weight may be exactly the same, they would have had more percentage of muscle at 25 than at 70. Mainly, that is because we lose muscle cells as we age. When younger muscle cells get damaged, they are quickly repaired. That is not the case with older muscles.

Decreases in growth hormone, testosterone and estrogen levels may account for the loss of muscle fiber and the inability of tissue to replenish itself. However, recent research is suggesting  that the stem cells in the muscle are not able to respond to damage or to aging the way they did when we were younger. The muscle cells we are left with are worn out. So, when we talk about metabolism, what we are really talking about is how efficiently the muscle cells of our body burn the energy we take in. Energy is delivered to the body in the form of calories, and if you keep your caloric intake exactly the same as you get older, those unburned calories end up as fat.

However, all is NOT lost! Several studies have shown that weight and resistance training exercise, even among individuals in their 80s and 90s ,works. It not only helps the muscle cells get bigger, it makes the muscles stronger.So, weightlifting at any age offers low risk and great benefit to our health. Building muscle and joint strength can also help fight other unfortunate aspects of aging, arthritis and inflammation. As always, prevention is better than cure, so start adding strength to your body today!