Inherited injuries?
Sometimes you know why you got injured – a sudden increase in mileage, say, or a switch to different shoes. The mystery is why your training partner, who was doing all the same things, didn’t get injured. There’s some luck involved, and there are also individual differences in running stride and body proportions. But there’s also mounting evidence that the basic structure of your tendons and ligaments depends on certain genetic variants that are passed on within families. Some people, it turns out, are born to be injured.
Researchers from the University of Cape Town published a review in the December issue of the British Journal of Sports Medicine summarizing the current evidence on the genetic risk of softtissue injuries. In one study, for example, subjects with a particular variant of the col5a1 gene were 58 per cent more likely to suffer from Achilles tendon problems. Other gene variants have been associated with acl and tendon ruptures, tennis elbow and carpal tunnel syndrome. What these genes have in common is that they affect the properties of your collagen fibrils, which are the basic structural components of tendons and ligaments.
Does knowing your risk help? Direct-to-consumer genetics companies like dnaFit have begun marketing tests that tell you which gene variants you have. British 800m runner Jenny Meadows, who missed the 2012 Olympics with an Achilles tendon injury, says she switched from 14 runs a week to 11 runs and three cycling sessions after learning that she had a high genetic risk of tendon and ligament injuries. She went on to set an indoor personal best of 1:59.22 last year.
In their review, the University of Cape Town researchers sound a note of skepticism about these direct-to-consumer tests. The research is still too preliminary, they argue, and the genetic tests are too difficult to interpret without medical expertise and an accompanying clinical examination. They’re probably right, at least for now. Still, it’s useful to realize that not all tendons are created equal, and that some people – some families, in fact – will need to be more cautious than others in planning their training and recovery.