Does stretching make a difference? Make the most of your time, and use your head when deciding about stretching.
What? You’ve probably heard of both static stretching and dynamic stretching. Static stretching is done by performing a steady hold on a muscle. Dynamic stretching is active, using controlled repetitive complex movements which are done to warm up and wake up the muscles.
Why? Static stretching is useful to restore muscle length and optimal efficiency. Keep in mind that both short and overstretched muscles are weak so confirm that a muscle is actually short by observing your range of motion. Also, stretch after physical activity.
Who? People whose bodies are inherently stiffer than average should stretch, as should those getting a little older due to the natural decreasing flexibility with increasing age. Also people who don’t use their joints to the fullest (those who mainly sit for work), and those who use their muscles repetitively (both athletes and those with physical jobs.)
How? To perform static stretching, hold one length for 30 seconds, 5 times, daily for six weeks for maximal increase in muscle flexibility. For maintenance, hold the static stretch for 30 sec, for 1-2 repeats, less than daily, depending on your physical needs.
To perform dynamic stretching – which are specific to sport or any given activity – use gentle controlled, repetitive movements (leg pendulums), but not with ballistic or bouncing movements.
When? Static stretches should be done after an activity, but best is a time of day unrelated to your activity. Dynamic stretches should be done before activity as it is used to increase both temperature and or neuromuscular activation. (Static stretching is not a warm up.)
Injury risk? Static stretching before exercise does not prevent injury. It actually makes muscles weaker temporarily (1-2 hours) by 2-5%. This is detrimental for explosive sports such as jumping and sprinting. Research has shown that people who are stiffer than average and people who are more flexible than average both have twice the risk of injury as those of average flexibility. So static stretching will mostly help reduce the risk of injury to the stiffer people.
Research has not been done yet to support the claim of risk reduction benefit for dynamic stretching. However, some of the benefit of dynamic stretching is to maximize movement performance. Time and upcoming research may support the use of dynamic stretching to reduce the risk of injury as well.
Source: Shrier I., Does stretching help prevent injuries? Evidence based Sports Medicine (2nd ed) 2007; 36-58.