How Important is Flexibility?
Unless you grew up under a rock, at some point or another you’ve probably had an authority figure tell you that you have to improve your flexibility to prevent injuries.
“Make sure you stretch your hamstrings before class!” - Gym Teacher.
“Stretch your shoulders before practice.” - Coach.
“Stretch out your calves before running.” - Online Guru.
Even the American College of Sports Medicine, the primary authority on exercise recommendations in the US, recommends stretching 2-3 days per week at a minimum and daily to be most effective (1).
But are stretching and flexibility all they are cracked up to be? How important is it, really, to stretch every day and be able to touch your toes?
The answer is: it depends.
While that may seem like a cop out answer, there are several factors that determine whether having a high degree of flexibility is advantageous, as well as what types of individuals actually benefit from stretching.
The primary factor is determined by what your lifestyle and movement requirements look like. Starting from the most basic level, you must first ask yourself: “do I have enough flexibility to complete my daily activities?” and “do I have the flexibility to adequately get into the positions that I need for daily life?”
Luckily for most of us, daily life does not warrant an extreme amount of flexibility for us to be able to assume our normal positions and movements, such as navigating stairs, walking, sitting and standing, bending to pick up an object, getting in and out of the car, etc. Stretching, therefore, may not be extremely important for somebody who does not find themselves doing more extreme things than what I’ve mentioned above, as long as they are being mindful to incorporate some purposeful movement into their routine.
Most people reading this, however, are athletes who expect more from themselves than just the status quo of daily household tasks and likely have more intense movement requirements than simply sitting and bending over. How do CrossFit athletes, Weightlifters, Dancers, Golfers, and other athletes differ in their flexibility requirements?
Although the above-mentioned athletes do require more range of motion in certain joints and muscles than sedentary individuals, it is also not completely necessary for these athletes to spend 20 minutes or more mindlessly stretching every muscle that they think is tight.
In fact, most of the time, simply participating in one’s sport is enough of a stimulus to cause the body to adapt and become flexible enough to assume those positions comfortably and effectively. Furthermore, most sports actually do not require extreme range of motion demands, and some athletes, such as sprinters and powerlifters, can even experience improvements in performance if they have some degree of muscle tightness, which can improve explosivity and facilitate the stretch reflex. As long as you are easing into your movements gradually via an active and specific warm-up routine, it is likely that your body will develop the flexibility required to complete your athletic movements comfortably, especially if you are consistent (2). Barbell athletes, for example, will likely experience improvements in their squat depth simply by squatting, especially if they are willing to add in squat-specific drills such as pause squats that can allow the body the opportunity to adapt to that depth.
There are occasions, however, when simply “doing the sport” does not quite do the trick in improving one’s flexibility enough to actually assume the positions properly. For athletes such as Olympic Weightlifters, CrossFit athletes, dancers, and gymnasts, it may be necessary to add in some specific accessory “flexibility” or mobility training for those muscles or joints that are consistently limiting them from executing their sport’s movements.
Does this mean it’s time to start stretching?
According to the research, maybe not.
Recent evidence suggests that not only is static stretching ineffective at preventing injuries, it may also not be the most effective method of improving range of motion (2,3). While athletes may experience short-term improvements in flexibility after static stretching, the effects are generally neurologic and short-lived in nature. Furthermore, the body adapts to the types of forces that it is exposed to. Static stretching, therefore, improves one’s flexibility and skill in that specific stretch. For athletes who require active and explosive movements at end-range, stretching tends not to carry over well to those tasks (4).
So is there anything that can be done to more effectively improve flexibility and range of motion that will help with athletic movements and reduce injury?
Turns out, resistance training (weight lifting) seems to be the most effective intervention when it comes to improving sport-specific flexibility, reducing injury, and improving performance. More specifically, lifting weights throughout a joint or muscle’s full range of motion, starting and finishing each rep from a fully stretched position, has been shown to actually increase muscle length from a structural standpoint as well as improve one’s ability to USE that muscle through its full range.
To take it one step further, by adding a brief pause in the stretched position (while still resisting against the weight) or increasing time spent on the lowering phase, this strategy can be even more effective at improving one’s range of motion and resilience in that stretched position.
Now that’s not to say static stretching is all bad. For sports that require prolonged holds at a muscle’s endrange, such as dancing, static stretching can actually be fairly sport-specific and impart benefits that translate to the sport.
At the end of the day, research is now indicating that the vast majority of athletes don’t necessarily need to stick to a static stretching routine, and being “flexible” is not necessary for injury prevention so long as you have enough mobility to execute your desired movements or positions. What IS important is that these athletes build resilience by exposing themselves to lots of different movements and performing full-range resistance training when flexibility requires attention.
Dr. Brooks Kenderdine
PT, DPT, CSCS, USAW-1
Co-Owner | The PATH Rehab & Performance
References:
Nuzzo JL. The Case for Retiring Flexibility as a Major Component of Physical Fitness. Sports Med. 2020 May;50(5):853-870. doi: 10.1007/s40279-019-01248-w. PMID: 31845202.
Shrier I. Stretching before exercise does not reduce the risk of local muscle injury: a critical review of the clinical and basic science literature. Clin J Sport Med. 1999 Oct;9(4):221-7. doi: 10.1097/00042752-199910000-00007. PMID: 10593217.
Behm DG, Blazevich AJ, Kay AD, McHugh M. Acute effects of muscle stretching on physical performance, range of motion, and injury incidence in healthy active individuals: a systematic review. Appl Physiol Nutr Metab. 2016 Jan;41(1):1-11. doi: 10.1139/apnm-2015-0235. Epub 2015 Dec 8. PMID: 26642915.
