If you live long enough, the loss of some muscle mass is inevitable. However, exercise and judicious nutrition go a long way to minimize the loss of muscle with age. This loss of muscle with age is known as sarcopenia, and its effects are far from just aesthetic. Even if you were never a bodybuilder or athlete, the loss of muscle is of great concern because recent studies have associated the age-related loss of muscle with increased mortality. The human body works on a "use it or lose it" basis, and what is not used gradually dissipates. This could range from neurons in the brain to muscles. Muscles are often compared to engines, which is an apt comparison since we need muscles to move. If you have a car and never run it, after a while the car won't run at all for various reasons, such as a dead battery that prevents you from starting the car. Muscle is made to move, or more precisely, to be exercised, and without regular exercise, the muscles atrophy. When that happens, a number of diseases linked to physical inactivity emerge. These include cardiovascular disease, brain degeneration, type-2 diabetes, and even cancer. So the first rule for maintaining muscle as you age is to continue to exercise.
If nothing is done to prevent it, the body loses about 1.5% muscle each year after the age of 50, which increases to 3% by age 60. Studies show that 50% of those 80 or older have serious cases of sarcopenia, or age-related loss of muscle. Even a 10% loss of muscle mass leads to a decrease in immune function, and that explains why losing muscle sets you up for increased mortality. With a 20% loss of muscle mass, you lose strength and cannot participate in activities of daily living. There is also an increased risk of falling, resulting in broken hips. Many older people die within 3 months of breaking their hips. If the muscle loss goes up to 30%, the ability to independently take care of yourself decreases, and there are increased risks of lower wound healing. With 40% muscle loss, there is a significantly increased risk of death from pneumonia and respiratory disease. Consider that in most cases of death in older people that is attributed to "old age," the actual cause of death is often pneumonia, which relates to a failure of the immune response in the elderly. Since muscle is a primary site of glucose uptake and metabolism, using 80% of the glucose content in the body, losing muscle can set you up for type-2 diabetes. Muscle accounts for 30% of the resting metabolic rate, so losing muscle is a risk for obesity, which is associated with the release of inflammatory cytokines that further promote muscle loss.
In most cases, certain training concessions must be made because of the aging process. Older muscles . . .