Medical myths abound in most cultures, beliefs that are grounded in history or arising from a neighbor’s experience. A large number of these have no scientific backing. This is not to say they aren’t accurate or don’t work, only that there isn’t good evidence either way. But it is a very human trait to draw conclusions. We do this routinely about many issues regarding our health, our illnesses, and the therapies we use. (How about the one where you can catch an upper respiratory infection because of an open window?)

An oft repeated phrase in fitness and sports medicine concerns the importance of the pre-workout warm-up. For decades, the mantra was that you must stretch before any workout, although there was no good evidence documenting any benefits. These recommendations were necessarily based on anecdotal information since no study had been performed.

There is no question stretching has been touted as having many perks. Over the years, various attributes have been ascribed to stretching, claims made by numerous authorities and organizations. Perhaps most common is the reduction in the risk of injury. Purported to increase flexibility and enhance joint range of motion, it is believed this will result in fewer aches and sprains.

Additional positive effects of stretching reported include athletic performance and better circulation. Others proclaim it is able to improve one’s posture and reduce stress. Some of these claims seem understandable, possessing some logical mechanism of action. Enhanced mood and relief of tension headaches are probably associated with any physical activity that is slow, deliberate, and repetitive.

Numerous questions and controversies remain unanswered in modern medicine beyond the effects of stretching. There is much we do not know, partially due to the fact that placebo-controlled, double-blinded studies are exorbitantly expensive and difficult to perform. In such a study, the intervention being tested is compared to a placebo, a therapy known to have no benefit or action. The latter term, double-blinded, refers to the fact that neither the patient nor the clinician know who is getting the placebo and who the actual treatment.

Many therapies utilized in modern medicine have not yet been conclusively proven. In contrast, stretching has been extensively examined. The acute effects of static stretches on strength and power have received much attention of late. Numerous tests have looked at how well it actually achieves the many positive actions attributed to the physical activity that is stretching.

Predictably, there are different types of stretching and each seems to have its own pros and cons. The most frequently studied and most often performed is the static stretch in which one or more joints undergo a controlled continuous movement to the end range of motion, whereby the muscles are remaining in a lengthened position.

Surprisingly, static stretches, the kind most often performed by weekend warriors and casual athletes, may impair physical strength. Apparently, there are some improvements in range of motion but these seem to last only about 30 minutes. Therefore, any physical activity, be it training or competition, lasting longer would require repetition of the stretching routine to maintain those benefits.

Many in the sports medicine world have concluded that, given the evidence, for improved athletic performance and a reduced risk of injury, static stretches are not an optimal use of time. In contrast, a dynamic stretch is one accomplished while moving and has been shown in some quality studies to lead to increased power and range of motion. And take note, the duration of a static stretch is critical since holding a stretch for 60 seconds is apparently the most beneficial.

Static stretching is widely used in athletics, fitness, and clinical settings for supposed aids to performance and injury prevention. Unfortunately, the evidence indicates they can impair performance, including power, strength, and speed-related activities. Although the impairment is not significant, it would seem appropriate to warm up for your workout in some other manner.

Just because you’ve done it one way for years, doesn’t mean you can’t change. Time is passing, use yours prudently. Don’t waste time before a fitness activity by doing the same old thing. If you like stretching, it’s unlikely to damage anything, but the studies show it needs to be held for longer, with 60 seconds being the most recommended.

The recommendations have changed as our understanding of the workings of the human body have expanded. Physical activity, nearly regardless of the type, is an essential component of wellness. But the recommendations on the topic of stretching are no longer that you must…..but that you may. You probably aren’t hurting anything, except maybe your Olympic race times!

Dr. Conway McLean, DABFAS, FAPWHc, has offices in L’Anse and Marquette. He is a physician who specializes in treating lower leg, ankle and foot problems.