One of the Podcasts I subscribe to is Quirks and Quarks, from CBC, the Canadian Public Broadcaster. The latest episode has the main story about exercise, and ‘busts some myths’ related to exercise. There are a few different myths that are dealt with, but the one that affects me most is:
- Stretching before exercise doesn’t improve performance, or reduce injury; but actually impairs performance, and possibly increases the chance of injury.
That is not to say that warming up is a bad thing - some light exercise is actually beneficial, but stretching is not. For one thing, stretching causes miniscule tears in the muscles. This allows the muscles to move further, but actually impairs performance, as the muscles are not as strong as they were prior to stretching. This effect can be up to a 10% loss in strength. These micro-tears, which are the way the muscle can be improved in the long term, also increase the chance of further damage to the muscles. Think about how a small chip in a car windscreen can expand with just wind force, and you’ll get the idea. Forces can be focussed onto the weak point, causing catastrophic failure. This is not to say that stretching is _all _bad. In fact, a stretching session is great, even if you aren’t a sportsperson, as it increases the overall range of movement and flexibility. I may have to consider this as I run my training sessions this year for State. The other issue that was of some relevance, to me at least, was:
- Some people do not respond well to exercise, in the sense of building body mass, or improving fitness. Everyone improves health by exercise (although only regular exercise) but not everyone gets fit.
I was planning on running a beep test in the first weeks of my training schedule for the 15s this year, and then another in the final weeks, and see how much the girls improved. I think I’ll still do this, but it will be harder to berate them for not working hard enough if they don’t improve. Having said that, I suspect that the girls we select will be those that are genetically predisposed to improving with training, rather than the other way around.