By Sheri Colberg, Ph.D., FACSM
Overuse Injuries: Which Are Most Common and Who Gets Them?
By definition, an overuse injury is caused by excessive use of a particular joint. Overuse injuries are more common in people with diabetes because of structural changes in their joints caused by long-term elevation in blood glucose levels. But regardless of the contributing cause, all overuse injuries are treated the same way. Moreover, their onset can usually be linked to changes in athletic endeavors or techniques. For example, if you have been running 3 miles (5 kilometers) several days a week at a moderate pace and then you suddenly begin running 5 miles (8 kilometers) six days a week at a faster pace than before, you’re setting yourself up for an injury. You should make only gradual increases in your training duration, frequency, or intensity so that your body will have time to adapt. Exercise is all about causing damage to your muscles to stimulate their rebuilding to become stronger, faster, or more aerobic—a result that can occur only if you allow adequate time for recovery and recuperation.
Basically, all athletes have a higher chance of getting an overuse injury at some point by overstressing muscles, joints, and bones with repetitive or damaging movements, particularly by rapidly increasing their training. Some people are prone to developing overuse injuries, but their development is more often related to anatomical, biomechanical, or other considerations. For instance, imbalances between your strength and flexibility around certain joints (e.g., quads versus hamstring strength) can predispose you to hamstring pulls. Uneven body alignment, such as knock-knees, bowed legs, unequal leg lengths, and flat or high-arched feet, can also contribute. Even having old injuries leads to a greater likelihood of overuse injuries, along with factors like the type of running shoes you use, the terrain (hilly, flat, or uneven), and whether you work out on hard surfaces like concrete roads or floors or softer ones like grass, dirt or gravel trails, asphalt, and cushioned floors.
Many overuse injuries involve inflammation of an area, or redness, soreness, and swelling, designated as "itis" at the end of its name. Tendinitis is inflammation of tendons, which attach muscles to bones; it is a common overuse injury that results from a tendon rubbing repeatedly against a bony structure, ligament, or another tendon or from being impinged. Tennis elbow is a type of tendinitis on the outside of the elbow common in tennis players as well as rowers, carpenters, gardeners, golfers, and other exercisers who repeatedly bend their arms forcefully. Swimmers often develop tendinitis and other impingement syndromes in the rotator cuff (shoulder) because of the overhead movement required by the sport. In sports that involve running and jumping, tendinitis often occurs in the knee, foot, and Achilles (heel) tendons.
Anyone with diabetes is prone to developing overuse injuries with a slower onset that can limit movement around joints. Common injuries are shoulder adhesive capsulitis ("frozen shoulder"), carpal tunnel syndrome (wrist pain), metatarsal fractures (of the foot bones), and neuropathy-related joint disorders (e.g., Charcot foot) in people with peripheral neuropathy. Trigger fingers, which result in curled fingers because of shortening of ligaments, usually require cortisone injections or surgery to repair them. People who have had diabetes for a long time are additionally prone to nerve compression syndromes at the elbow and wrist that may be aggravated by repetitive activities, prolonged gripping, or direct nerve compression during weight training, cycling, and other activities. In most cases, good control of your blood sugars can reduce your risk for developing these injuries.
In my next column, you’ll learn more about preventing overuse injuries before you get them.
This column is excerpted from Diabetic Athlete’s Handbook (2009), which contains essential exercise-related information and examples for Type 1, Type 1.5, and Type 2 diabetic exercisers of all ages. More information is available at www.shericolberg.com.