Achilles tendon (AT)\u00a0injuries are common—upwards of 18% in runners (with a lifetime prevalence of 50%) and\u00a0affects approximately 1 million athletes per year. And, the injury rate increases significantly as we get older.<\/p>\n
Why is this tendon commonly inured? The answer is fairly simple, we put a lot of stress on the AT—it can be subjected to 8-10 times a person’s body weight during strenuous exercise. And because we put a lot of stress on it, we need to maintain the strength and flexibility of the AT\u00a0at a fairly high level. Unfortunately, maintaining a high level of strength and flexibility is a problem for most people.<\/p>\n
Strength needs to be maintained throughout the entire range of movement (approximately 70 degrees of ankle flexion). Flexibility needs to be enough to allow effortless movement through full range.<\/p>\n
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An easy\u00a0way to test\u00a0AT flexibility is to squat all the way down\u00a0keeping feet flat (no heel lift) and knees over the toes. Normal flexibility is\u00a0shown above.<\/p>\n
Maintaining enough strength to withstand 10 times body weight is difficult—it involves jumping and sprinting exercises. Most AT injuries occur at lower stress levels,\u00a0so maintaining a level of strength of 2-4 times body weight would be enough to prevent most AT injuries (for non competitive athletes).<\/p>\n
Next month I will present exercises that will help maintain AT strength and flexibility.<\/p>\n