For a long time, everybody has believed that stretching before exercise is a must to avoid injuring yourself. But now things appear to be changing. Any one remember the 2005 ashes series (of course you do!!). Freddie Flintoff somehow managed to avoid injuring himself despite being right at the end of his international career, and having suffered countless injuries leading up to the tour. One of the things this was attributed to was the fact that he stopped stretching as part of his warm up when preparing for a spell bowling. To understand the theory behind this, we first need to understand a little of the science.
Muscle fibres are made up of microscopic segments called sarcomeres (see diagram bellow). There are millions of these in each muscle fibre, and the function of them is to shorten the muscle fibre- resulting in contraction of the muscle. To do this, the “Z lines” in the diagram must come closer together, so the thick filaments must slide along the thin filaments. They do this using tiny little “hook and lever” type proteins called myosin heads. These heads come from the thick filament, and attach onto the thin filament, and then the lever swings, causing the two filaments to slide past each other.
So whats wrong with stretching??
When you stretch, you lengthen the muscle fibre, meaning the Z lines are further apart. This in turn means that there are fewer myosin heads connecting the thick and thin filaments. As a result, when you then powerfully contract the muscle, it is more likely that the myosin heads might “lose their grip”, resulting in a muscle tear.
A recent study published in the Journal of Strength and Conditioning Research found that when weightlifting, those who did not stretch before training were able to lift more weight than those who did. It also found that those who stretched before training reported feeling more unstable than those who did not.
It is important to note three things when considering this: firstly, the stretching I am talking about is static stretching ie. stretching a muscle until it hurts and then holding it for a set period of time. This is very different from dynamic stretching which involves contraction of the stretched muscle, and is generally a much more effective way of stretching anyway! Secondly, I am only talking about stretching before exercise… stretching afterwards is a very different kettle of fish, and generally is much more worthwhile. Thirdly, I am only talking about stretching, NOT warming up… warming up is still key both to avoiding injury, and protecting your cardiovascular system, as well as making the most out of your workout.
And finally, heres a video clip to reinforce the point!! (Rule #18 always limber up!!)