Swimmer Mags article on stretching ...

The provocative USMS article helps get us thinking about an important aspect of our fitness and meet preparation programs. The article challenges what coaches and swimmers have been doing for a long time and indicates that various traditional stretches performed just prior to exercise causes injury and hurts performance. If true, there may be liability considerations too. The article recommends an active warm up just prior to a workout and periodic stretching of the shoulder muscles either several hours before or several hours after a workout (not right before a workout). The author of the USMS article noted elsewhere that elite swimmers can often be seen performing what he believes are contraindicated stretches just before they swim their heat and is concerned that others may imprudently mimic them because of their competitive successes and their crediting in part their stretching regimes (eg, Michael Phelps). The author is concerned that "Many people become addicted to self manipulation of joints because of this temporary inhibition of pain and muscle relaxation...The stiff and achy sensation of DOMS (delayed onset muscle soreness) encourages a swimmer to stretch their shoulder to the extreme in an effort to provide relief and achieve a loose feeling." A birds-eye view of the body of scientific and empirical evidence may be helpful and also explain the apparent dichotomy to some between the USMS article and the Masters swimming pages this month in Swimming World magazine. Over the past few years, some studies have theorized that “acute” vigorous stretching performed seconds or minutes immediately prior to a competition event may not prevent injury and enhance performance but instead might be detrimental. This new evidence mostly involved testing leg muscles or hand grip strength in the laboratory after a brief course of vigorous stretching. Some results, but not all, found a small decrease in muscle strength of unknown clinical significance. “Acute” stretching decreased running speed in one study, increased it in another, and had equivocal results in two others. Kristie-Lee Taylor, PhD, and her colleagues found that 15 minutes of dynamic warm up (bending, swinging, twisting the arms, legs and torso for 15 minutes) was better than 15 minutes of lower body static stretching to increase 20 meter running sprint and vertical jump performance performed 2-3 minutes later. Because athletes rarely do such pre-competition workouts in isolation, ie without sport-specific warm ups performed as well, the researchers considered such a comparison irrelevant. When the test subjects followed either test regimen with a sport-specific warm up, there were no differences between the static and dynamic warm up groups. David Behm, PhD and his colleagues found in laboratory cyclists impaired reaction time and movement examined within one minute after a static stretching routine. Janne Avela and his colleagues found loss in calf strength after 1 hour of continuous passive stretching induced by a machine that returned to normal within 15 minutes. Such studies have little if any practical significance for Masters swimmers. There are good reasons why some studies show that stretching increases performance and reduces injury, some show the opposite and some show no effect. For example, how stretching was defined and how injuries were assessed. One of the most relied upon studies warning against stretching for injury protection when re-analyzed to focus on muscle injuries found that stretching reduced muscle injuries. All things considered, Krista Woods, PhD, and her colleagues concluded that "a warm-up and stretching protocol should be implemented prior to physical activity. The routine should allow the stretching protocol to occur within 15 minutes immediately prior to to the activity in order to receive the most benefit." “Acute” or static stretching studies have not been performed in swimmers. Because swimmers use muscles differently than virtually every other sports, studies in selected groups like jumpers and runners warning against stretching (even though they are more than balanced by studies recommending stretching) should not overly constrain swimmers from stretching. Furthermore, 1) compared to running sprinters and explosive jumping, swimmers move in relative slow motion, likely removing the the possible "acute" stretching effect 2) competition swimmers virtually always conduct an in-pool warm up, which would also virtually eliminate any "acute" stretching effect 3) swimmers who perform static stretching lasting at least 15 minutes do so relatively long before the heat, not merely 2-3 minutes before (during which they are listening to music, resting and finally performing a brief routine of calming exercises), thus further minimizing any "acute" stretching effect 4) the stretching performed by swimmers before a competition heat would more likely be considered a 'dynamic' workout than a 'static' workout; thus, the possible "acute" stretch effect on running and jumping may be further irrelevant for swimmers If a detrimental effect of stretching occurs in some swimmers, it is likely that ballistic or excessive stretching beyond a breaking point and sufficient to induce lasting pain caused the injury and/or reduced performance. It would be surprising though that elite swimmers and those aspiring to join them have not observed such an effect (beyond obvious over stretching that caused significant pain or injury) if it is relevant in view of the dozens-hundreds of swim meets they each entered while actively monitoring their performance and its development. Apparently their coaches have not observed it either. Specific research is called for, especially because greater numbers of us are entering Masters swimming later in our lives when many of us are more prone to injury. Nevertheless, the pre-event stretching recommended by the authors of the USMS article combined with a good swim warm up will help prepare swimming muscles and psyche for a better swim heat. The USMS article should not dissuade swimmers from regular stretching, preferably daily. According to Ian Shrier, MD, PhD, in his review of substantial peer-reviewed evidence, “regular stretching improves force production and velocity of contraction…These results are consistent with the basic science evidence and mirror the results observed with respect to stretching and injury.” Most athletes and billions of non-athletes rely on regular stretching for its benefits on fitness, performance, range of motion, injury protection, injury recovery and good health. Also, regular stretching has therapeutic benefits for aging bodies just as swimming itself does (as noted also in this issue of Swimmer). Dr. Taylor and her colleagues concluded, "A well-designed warm-up can assist the athlete in mentally focusing on the upcoming task and to bring about various physiological changes to optimize performance." A routine of regular stretching, preferably daily and including stretches that are contraindicated by the article’s authors, will help build a foundation for health and performance if not done to the breaking point. I thank George Edelman and Drs. David Behm, Ian Shrier, Kristee-Lee Taylor, Malachy McHugh and Krista Woods for their help. PS Jim Miller, MD, member of USMS's Sports Medicine and Science Committee wrote last fall, "Swimming injuries are almost always related to stroke technique flaws. Overuse injuries in swimmers may involve the neck, lower back, elbow, or knee, but by far, the most common injuries involve the shoulder...Be very careful while stretching. A lot of accomplished swimmers are flexible, however it is important to not allow this natural gift of flexibility to become a problem. If stretching is overdone, the shoulder will become unstable and more susceptible to injury." From Jim Montgomery and Mo Chambers in Mastering Swimming, "Since flexibility is critical to improving swimming, the most essential element of any dry-land program is a safe and thorough stretching routine...Be patient with stretching and try not to rush your progress by overstretching, which can injure your muscles. Proper stretching leaves you relaxed and feeling good." From Ed Nessel in Swim to Win, "Cold makes everything tight. And tight is not conducive to fast, powerful movement. Cold muscle fibers need warming before they are put to work...It increases the range of motion and the force with which muscle moves by improving the fibers' ability to contract. It also protects and prepares the muscles and their corresponding connective tissue." According to Marc Safran, MD and his colleagues, "Warm-up and stretching are essential to preventing muscle injuries by increasing the elasticity of muscles and smoothing muscular contractions. Improper or excessive stretching and warming up can, however, predispose to muscle injury."

The provocative USMS article helps get us thinking about an important aspect of our fitness and meet preparation programs. The article challenges what coaches and swimmers have been doing for a long time and indicates that various traditional stretches performed just prior to exercise causes injury and hurts performance. If true, there may be liability considerations too. The article recommends an active warm up just prior to a workout and periodic stretching of the shoulder muscles either several hours before or several hours after a workout (not right before a workout). The author of the USMS article noted elsewhere that elite swimmers can often be seen performing what he believes are contraindicated stretches just before they swim their heat and is concerned that others may imprudently mimic them because of their competitive successes and their crediting in part their stretching regimes (eg, Michael Phelps). The author is concerned that "Many people become addicted to self manipulation of joints because of this temporary inhibition of pain and muscle relaxation...The stiff and achy sensation of DOMS (delayed onset muscle soreness) encourages a swimmer to stretch their shoulder to the extreme in an effort to provide relief and achieve a loose feeling." A birds-eye view of the body of scientific and empirical evidence may be helpful and also explain the apparent dichotomy to some between the USMS article and the Masters swimming pages this month in Swimming World magazine. Over the past few years, some studies have theorized that “acute” vigorous stretching performed seconds or minutes immediately prior to a competition event may not prevent injury and enhance performance but instead might be detrimental. This new evidence mostly involved testing leg muscles or hand grip strength in the laboratory after a brief course of vigorous stretching. Some results, but not all, found a small decrease in muscle strength of unknown clinical significance. “Acute” stretching decreased running speed in one study, increased it in another, and had equivocal results in two others. Kristie-Lee Taylor, PhD, and her colleagues found that 15 minutes of dynamic warm up (bending, swinging, twisting the arms, legs and torso for 15 minutes) was better than 15 minutes of lower body static stretching to increase 20 meter running sprint and vertical jump performance performed 2-3 minutes later. Because athletes rarely do such pre-competition workouts in isolation, ie without sport-specific warm ups performed as well, the researchers considered such a comparison irrelevant. When the test subjects followed either test regimen with a sport-specific warm up, there were no differences between the static and dynamic warm up groups. David Behm, PhD and his colleagues found in laboratory cyclists impaired reaction time and movement examined within one minute after a static stretching routine. Janne Avela and his colleagues found loss in calf strength after 1 hour of continuous passive stretching induced by a machine that returned to normal within 15 minutes. Such studies have little if any practical significance for Masters swimmers. There are good reasons why some studies show that stretching increases performance and reduces injury, some show the opposite and some show no effect. For example, how stretching was defined and how injuries were assessed. One of the most relied upon studies warning against stretching for injury protection when re-analyzed to focus on muscle injuries found that stretching reduced muscle injuries. All things considered, Krista Woods, PhD, and her colleagues concluded that "a warm-up and stretching protocol should be implemented prior to physical activity. The routine should allow the stretching protocol to occur within 15 minutes immediately prior to to the activity in order to receive the most benefit." “Acute” or static stretching studies have not been performed in swimmers. Because swimmers use muscles differently than virtually every other sports, studies in selected groups like jumpers and runners warning against stretching (even though they are more than balanced by studies recommending stretching) should not overly constrain swimmers from stretching. Furthermore, 1) compared to running sprinters and explosive jumping, swimmers move in relative slow motion, likely removing the the possible "acute" stretching effect 2) competition swimmers virtually always conduct an in-pool warm up, which would also virtually eliminate any "acute" stretching effect 3) swimmers who perform static stretching lasting at least 15 minutes do so relatively long before the heat, not merely 2-3 minutes before (during which they are listening to music, resting and finally performing a brief routine of calming exercises), thus further minimizing any "acute" stretching effect 4) the stretching performed by swimmers before a competition heat would more likely be considered a 'dynamic' workout than a 'static' workout; thus, the possible "acute" stretch effect on running and jumping may be further irrelevant for swimmers If a detrimental effect of stretching occurs in some swimmers, it is likely that ballistic or excessive stretching beyond a breaking point and sufficient to induce lasting pain caused the injury and/or reduced performance. It would be surprising though that elite swimmers and those aspiring to join them have not observed such an effect (beyond obvious over stretching that caused significant pain or injury) if it is relevant in view of the dozens-hundreds of swim meets they each entered while actively monitoring their performance and its development. Apparently their coaches have not observed it either. Specific research is called for, especially because greater numbers of us are entering Masters swimming later in our lives when many of us are more prone to injury. Nevertheless, the pre-event stretching recommended by the authors of the USMS article combined with a good swim warm up will help prepare swimming muscles and psyche for a better swim heat. The USMS article should not dissuade swimmers from regular stretching, preferably daily. According to Ian Shrier, MD, PhD, in his review of substantial peer-reviewed evidence, “regular stretching improves force production and velocity of contraction…These results are consistent with the basic science evidence and mirror the results observed with respect to stretching and injury.” Most athletes and billions of non-athletes rely on regular stretching for its benefits on fitness, performance, range of motion, injury protection, injury recovery and good health. Also, regular stretching has therapeutic benefits for aging bodies just as swimming itself does (as noted also in this issue of Swimmer). Dr. Taylor and her colleagues concluded, "A well-designed warm-up can assist the athlete in mentally focusing on the upcoming task and to bring about various physiological changes to optimize performance." A routine of regular stretching, preferably daily and including stretches that are contraindicated by the article’s authors, will help build a foundation for health and performance if not done to the breaking point. I thank George Edelman and Drs. David Behm, Ian Shrier, Kristee-Lee Taylor, Malachy McHugh and Krista Woods for their help. PS Jim Miller, MD, member of USMS's Sports Medicine and Science Committee wrote last fall, "Swimming injuries are almost always related to stroke technique flaws. Overuse injuries in swimmers may involve the neck, lower back, elbow, or knee, but by far, the most common injuries involve the shoulder...Be very careful while stretching. A lot of accomplished swimmers are flexible, however it is important to not allow this natural gift of flexibility to become a problem. If stretching is overdone, the shoulder will become unstable and more susceptible to injury." From Jim Montgomery and Mo Chambers in Mastering Swimming, "Since flexibility is critical to improving swimming, the most essential element of any dry-land program is a safe and thorough stretching routine...Be patient with stretching and try not to rush your progress by overstretching, which can injure your muscles. Proper stretching leaves you relaxed and feeling good." From Ed Nessel in Swim to Win, "Cold makes everything tight. And tight is not conducive to fast, powerful movement. Cold muscle fibers need warming before they are put to work...It increases the range of motion and the force with which muscle moves by improving the fibers' ability to contract. It also protects and prepares the muscles and their corresponding connective tissue." According to Marc Safran, MD and his colleagues, "Warm-up and stretching are essential to preventing muscle injuries by increasing the elasticity of muscles and smoothing muscular contractions. Improper or excessive stretching and warming up can, however, predispose to muscle injury."