About 5-12% of runners get Achilles tendinitis (or tendinosis if you are a science nerd) at least once in their lifetime. I’ve had a few rounds of it myself. As a minimalist runner, I’m more susceptible to Achilles pain than to knee- or shin injuries. I’ve never had anything crippling, but at times I’ve been worried about it. There are many different recommended treatments, from ultrasound to stretches to surgery. Many of these are prescribed based on experience, and are not necessarily backed up by science.
Eccentric calf stretches is one treatment has more going for it than a great name. It is also backed by several studies. The eccentric part is that you go down on one foot and up on two. The point is to lower your heels slowly while stretching your quads. In short it’s the opposite of a heel lift. I have never fully understood the theory behind it, so I was happy to find this article:
It’s long, but it’s nice to have a bit of background knowledge. Apparently the whole point of eccentric stretches is that you:
- Don’t do any sudden or violent movements
- Avoid concentric stretches (normal heel lifts)
One theory of how it works is this: After overtraining, the tendon’s collagen fibers often grow back a bit messy. Typically, that can lead to a nodule or a weakened tendon. But when you carefully stretch the tendon while using your quad muscles (see image), you only break down the “messy” fibers that go the wrong way. The fibers that go the right way can handle more stretching before breaking, so they will stay intact. If you jump around or do concentric heel raises, you break down the bad tissue and the good, and the condition will heal more slowly.
It’s just a theory, but to me it makes sense. For me, knowing why I’m doing something is the only way to get it done.
Anyway I really recommend the article to all who are experiencing tendon trouble.