By Erin Higgins, DPT
Jumpstart Physical Therapy
As you age, your body naturally changes such that you often cannot do activities with the same speed, power, intensity, and/or duration you once could. This is why most professional athletes are retired by the age of 40. It is important to understand your body's limits; pushing past those limits will put you at risk for injury.
This article will explore some of the effects of aging on your body, how those changes may affect your workout, and how you can slow negative such changes.
Bone loss: Peak bone density occurs around the age of 30. After that, more bone is lost than is made. Due to decreased efficiency of the body's ability to store calcium and minerals, bones become less dense with age. This puts you at risk for osteopenia and osteoporosis, which increase your risk for breaking a bone. This is not common until after age 50.
Appropriately loading your bones with weightlifting and weight-bearing activities, such as walking/running/elliptical, will slow or even stop such bone loss. Calcium/vitamin supplements may also be beneficial (speak to your doctor for more information about the benefits of starting such supplements).
Joint stiffness: Joints are covered with cartilage and surrounded by a thick capsule that is filled with fluid to help the bones easily move over one another. As you age, joints lose fluid and cartilage degenerates. As a result the bones do not move as easily, causing them to feel "stiff." This is also the cause of arthritis. The most commonly affected joints are hips and knees due to constant weight bearing and pounding, as well as the fingers due to repetitive use. Joints will typically feel stiff in the morning and after prolonged sitting or standing.
Previous injury or surgery to a joint, such as an ACL tear/reconstruction, significantly increases your risk for joint stiffness and also leads to much earlier onset of stiffness and/or arthritis - such joint irritation is not uncommon at ages of even 25, 30 or 35 in those who experienced a severe injury or surgery as a teenager. To decrease stiffness, keep moving! Stay active and loose to decrease the pressure on the joints.
Loss of muscle tissue: Muscles do not work as effectively as you age. Individual muscle fibers shrink in circumference, fat is deposited where muscle once was, and blood flow to the muscles slow. As a result, muscles become smaller and have less contractile tissue, leading to decreased muscle strength and force. Unfortunately, the progress of muscle loss typically starts between the ages of 30-50. By regularly lifting weights and performing cardiovascular activities to load the muscles, you can slow the effects of aging on muscle tissue. You can also gain strength due to neural adaptations (improved efficiency of the muscle). Exercising also facilitates blood flow to the muscles, which will help keep your muscles healthy.
Slower reflexes: Due to changes in the make-up of muscles and tendons, you will have slower reflexes as you age. Specifically, with age you tend to lose Type 2 muscle fibers, also known as fast-twitch muscle fibers. These fibers are responsible for quick reactions and powerful activities -- think sprinting and jumping. By performing careful, quick bursts of movement, you can slow the loss of such fibers. In other words, use it or lose it!
Don't despair. Getting older doesn't have to mean getting old. Regular exercise can decrease the effects of aging, including minimizing bone loss, joint stiffness, and muscle loss while improving your reflexes.
It is important, however, to understand that the effects of aging CANNOT be REVERSED. And, unfortunately, those aging effects occur much quicker than one would hope - often by the young age of 30! Therefore, knowing your body's limits is extremely important to avoid setbacks and minimize your risk of injury. Your muscles will become more easily damaged as you age, leading to increased soreness. The mature body also doesn't recover as quickly from injury as a child's may. It's completely natural that you may not be able to perform some exercises at the same level you once did. But it doesn't mean you can't still perform them at all. Simply modify! Instead of jumping to the high box, jump to the medium box. Instead of lifting 20#, lift 15#. Little modifications will go a long way toward keeping you healthy, decreasing your risk for injury, and slowing the effects of aging on your muscles, joints, and bones.