How do my muscles change as I age?

For many people, muscle mass declines as we age and some authors have reported that fat infiltrates the muscles as they age. However, a new study shows that long-term intense exercise preserves muscle mass, strength, and prevents fat infiltration. With prolonged intense exercise, people can not only maintain their muscle mass and strength, but they can actually get stronger. This can help with falls and other strength related injuries that older adults experience. Check out the study at https://physsportsmed.org/doi/10.3810/psm.2011.09.1933

The changes seen in our muscles as we age are largely the result of loss of muscle cells, decreased size of muscle fibers, and increased muscle stiffness. Most of the muscle changes seen with aging are caused by the loss of lean muscle mass, or sarco penia.