Stretching and Injury Prevention
After hours of sleep or sitting at a desk, the most common action upon standing is to stretch. The muscles are relaxed and have experienced decreased blood flow as there is less demand for strong circulation while immobile. Stretching helps to stimulate circulation and bring newly oxygenated blood to the tissues. The heart rate increases and we take a deep inhalation filling up our lungs, moving in just the right way to release tension and prepare the body for movement. Many yoga and PE classes still begin sessions with a nice breathing and stretching routine. This kind of light stretching can be beneficial for signaling to the muscles that they are about to begin work and prime tight, cold fibers, however, if included in a pre-run warm-up, can also lead to or cause injury.
In science, inaccurate information is often promulgated as seemingly legitimate and valid–albeit inadequately-tested–ideas have the possibility of improving our lives, only for it to be completely debunked as evidence collects. To stretch or not to stretch is now a decades old debate that remains to befuddle people; continuing to adhere to ideas without enough knowledge of new studies that have elucidated the misconception. For years it was touted that stretching before exercise can assist in reducing the risk for injury by increasing muscle length, enhancing range of motion and making them more elastic. Studies supporting this idea were based on data collected from the British military who observed a reduction in injuries from 6%-1% with a regular stretching routing before training. With advancements in exercise physiology, recent studies involving athletes from a wide range of sports including football, wrestling, gymnastics and running suggest that there is no performance enhancement stimulated by stretching alone. In some cases, when the muscle is tight pulling on it too much can tear the tissue which becomes aggravated once the activity commences and endures.
In a study delivered to the 2011 Annual Meeting of the American Academy of Orthopaedic Surgeons, Daniel Pereles, M.D. presented his results that included 2,729 recreational and elite runners all of whom ran at least 10 miles per week. The participants were randomly divided into two groups: a stretch group and non-stretch group. Runners in the stretch group were instructed to carry out a 3-5 minute leg stretch routine prior to their run. Surprisingly, what he found was that the isolated act of stretching didn’t influence the rate of injury; Pereles defined injury as any complication that prevented running for at least a week. Factors that contributed to running impairment was a history of chronic injury, continuous high mileage training, being a heavier runner, and changing pre-run stretching routines (switching from consistently non-stretching to stretching). Participants who stretched before the study and were assigned to the non-stretch group had a 23% increase in injuries; runners who were assigned to the stretch group with a history of not stretching experienced a 22% rise, equating to about a 40% increased risk for injury for the groups combined. Pereles concludes that one should follow their own regimen in the interest of safety and what has worked for them, he says, “If it feels good for you to stretch before you run, then continue if you have the time, but if it doesn’t feel good, and you like to run and then stretch, or not stretch at all, then that’s fine too.”
The body and brain are very efficient and adapt to repetition with ease. Our tissues and circuitry respond to pattern and routine; adjusting fibers to accommodate expected stress load. With frequent exercise, the body uses less calories to complete the sport in comparison to how much fuel was needed at the beginning of a new training plan–it becomes more efficient in how it uses calories. It takes about 3 weeks to adapt to a new activity and fashion new habits. If you have come from cycling, a sport that requires muscles to be supple, and dive into running, a sport that has eccentric contraction in the muscles, your risk for injury is increased. New actions demand a period of adaptation and pushing beyond what they are currently capable of will always place you in a precarious position, that is why gradually increasing mileage, intensity, and stretching is best.
If we consider the British military recruits who experienced a drop in injury occurrence and that most professional athletes regularly stretch as a pre-workout warm-up, it appears that there must be some benefit to stretching; however, their routines actually involve other dynamic trends such as calisthenics and light cardiovascular activities not just cold extensions. Stretching is best performed after the muscles are already warm. One of the best pre-run training techniques is to simply walk for a few minutes. It has a better effect on circulation than does stretching, and if you are interested in incorporating stretching into your training, the muscles will be warm enough to do so safely. It should be noted that there is an advantage to extending range of motion. If you encounter an obstacle while running and leap or trip over it–or land in an awkward position–being flexible can prevent an injury by having the ability to make a wide stride without pulling the muscle.
A person can suffer an injury from stretching because they don’t actually know how to stretch properly. Perhaps they have observed other runners demonstrations or have looked up on the Internet what stretches are valuable for their sport and plunge right in. Over-stretching is a sure fire way to create small tears and tissue damage. Always approach the first stretches slowly and gingerly; it helps to grip the muscles with your hands and give them a quick massage to facilitate blood flow. If you ever feel pain or noticeable discomfort, you have stretched too far. The sensation should be somewhat pleasurable and work with your current flexibility.
In all, moderate stretching before a run does not affect the risk of injury. Switching to a new stretching routine and over-stretching cold muscles will put you at a greater risk for complication. Stick with what works for you and don’t let another person’s preferred regimen influence your own if you are satisfied. Furthermore, stretching does not enhance performance–runners are equally as fast regardless of stretching endeavors.