Seeing as stretching is a common and traditional part of Taekwondo, it may seem like a shock to some when they are told that stretching can be unhealthy and detrimental to their performance. Specifically, static stretches have been proven to be damaging to runners by studies ranging from the deserts of Las Vegas to the frigid areas of Scandinavia. All over the world, the traditional idea of stretching and holding a certain position before a workout is being thrown out the window.
“Science has moved on… many athletes’ warm-up regimens are not only a waste of time but actually bad for you. The old presumption that holding a stretch for 20 or 30 seconds, known as static stretching-primes muscles for a workout is dead wrong. It actually weakens them.”
-William Holcomb, PhD, University of Nevada, Las Vegas.
While the research has largely been conducted on sports such as running, Taekwondo contains many of the same elements. Taekwondo contains elements of both cardiovascular and anaerobic exercise, as well as many of the same muscular movements in the legs as running sports. Overstretching is a problem, especially when done to the point of pain, and will weaken both strength and speed, such as diminishing the "snap" of a kick, before a workout or sparring match. The muscles will sometimes not even cope with the strain they are being forced to exert, causing collapse or severe injury if overstretched. Stretching has been proven in tests to decrease the force a muscle can exert by about 30% for a short time after the initial stretch.
What do kinesiologists and scientists recommend instead? A warm up that begins slowly and increases in intensity. For example, before class, it would be recommended to first jog, then run, then sprint for a short while. Basically, this is just cardio/aerobic exercise. For kicking exercises, it would be recommended to begin swinging the leg back and forth, slowly working up to a stretch kick. This is called dynamic stretching. Why is this better? Exercises that put your body into motion supply blood to the muscles of the body, while warming the muscles, which allows them to extract and use oxygen from the blood stream far more effectively. Oxygen is required to produce ATP (Adenosine Triphosphate)", a molecule that breaks down in order to release energy to the body. "Cold" stretching skips this vital step, which can do more harm than good.