Some people may ask what the benefit of stretching is. ‘After all,’ they say, ‘I’ve gotten along without it for many years.’ There have even been some reports in the media that researchers are now questioning the theory that stretching prevents injuries to ‘normal people,’ but may have some protective value for athletes. Nowhere in any of these reports did I see a definition for the term athlete.
Activity levels are on a continuum rather than sharply delineated between athlete and non-athlete. Actually, it is true that if you never move, you will never get hurt. That is another issue altogether.
Flexibility is a generalized term referring to the range of motion in joints. There is an inverse relationship between flexibility and stability in a joint. At one extreme, the joint is so immobile that the person can barely perform normal everyday self-care tasks without pain or injury (tight hamstrings are a risk factor for low back pain). The other extreme is someone with joints that move far beyond the normal range of motion, but the joints are very unstable and vulnerable to injury. Some people are born with hyper-mobile joints or develop them from excessive stretching.
People who have previously torn ligaments or tendons will often have this condition of hyper-flexibility. People in certain sports may develop joint problems later in life due to hyper-flexibility. Many of the standard tests used by doctors and physical therapists to diagnose injuries rely on range of motion assessment. Between the extremes is the optimal range of motion, which provides both adequate flexibility and adequate stability. There is fairly wide variability for individual differences within the optimal range.
Stretching is often perceived as requiring the practitioner to stretch to the point of pain. Pain during stretching is not only unnecessary but also counter-productive. There is more than one kind of stretching. There is dynamic stretching in which the body moves into and out of the stretch with speed and force. Dynamic stretches carry a higher risk of causing injury and are therefore only recommended for athletes in sports that require a dynamic stretch as part of the performance of the sport, such as baseball pitchers, gymnasts, hurdlers and some martial artists.
Athletes in these sports can use light aerobic activity or calisthenics, followed by static stretches, to prepare for the more risky dynamic stretches. Athletes in other sports and fitness enthusiasts should stick to the safer methods of static stretching. In static stretching, the joint is brought slowly and carefully to the point where the stretch is felt and is held in that position for 20 to 30 seconds.
There is also assisted stretching in which the joint is stretched by another person. There is PNF (Proprioceptive Neuro-muscular Facilitation) stretching that is used extensively by physical therapists. PNF is usually an assisted stretch, although there are quite a few PNF stretches that can be performed solo.
PNF consists of a pre-stretch phase, where the joint is taken to a point just short of where the stretch is felt and the person being stretched resists the stretch for six seconds. The relaxation phase follows, where the joint is stretched for 20 seconds without resistance. The pre-stretch contraction actually allows the stretch to be taken deeper, without discomfort, than passive stretching.
Many athletes stretch prior to weight training, games or sports practice without warming up first. Stretching cold is more likely to cause injury and is less effective than doing so after the body temperature has increased from light walking, jogging, stationary cycling or calisthenics. Warming up raises the viscosity of the bursal fluid in the joints and increases the elasticity of the tendons and ligaments.