How Does Stretching Really Prevent Sports Injury?
The truth about how stretching and flexibility training prevents injury and improves athletic performance.
by Brad Walker | First Published November 30, 2012 | Updated March 13, 2019
Here’s what they found…
- When adjusting for all potential risk factors, there remained no significant difference between the two stretching groups.
- When comparing injuries which prevented running in excess of 1 or 2 weeks, there is no significant difference between the stretch and no stretch groups whether adjusting for other risk factors or not.
- There was no statistically significant difference in injury rates between the stretch and no stretch groups for any specific injury location or diagnosis.
- And finally; over a three-month period there was no statistically significant difference in injury risk between the pre-run stretching and non-stretching groups. Stretching neither prevented nor induced injury when compared to not stretching before running.
So it’s no surprise that I’m often asked: Is there any scientific evidence that proves stretching will prevent a sports injury (or make me a better athlete)? And if I’m honest (and respectful of the research), I have to reply by saying; Not a lot.
But before you give up stretching altogether, let me ask another question. Is there any scientific evidence that doing strength training before playing sport will prevent sports injuries (or make you a better athlete)?
While the answer to this question is also a no, it doesn’t mean that strength exercises aren’t beneficial, or don’t have a place in your training program. And the same applies to stretching and flexibility training.
While doing a few hamstring stretches before running onto the field or hitting the gym will not prevent injury (which is exactly what the USATF study did), the same can be said for push-ups, or bicep curls, or any other strength exercise. But stretching, just like push-ups, was never meant to be used in this way, and this is where the so-called scientific research falls short.
The research is flawed
I know this may seem like a bold or arrogant claim, but I’m not the only one who is a little cautious when it comes to research findings. Greg Nuckols, in his article, When To Trust Research Findings, begins by saying…
Transcript from video (click to open)
But before I do that, I just want to comment on a couple of mistakes that I see a lot of people making when they are interpreting scientific research or research studies.
The first mistake I see is that a lot of people only read the conclusion of the research study and this is a big mistake. Now I can understand it because a lot of studies that are published online will only show you the conclusion or sometimes even just an abstract of the conclusion. And then to read the full story, you have to pay to actually access it. So I can understand why a lot of people only read the conclusion. But the problem with that is that there’s no context to where the conclusion came from. So you don’t know exactly how the study was conducted. You don’t know the methods used. You don’t know the procedures that went into the study. And reading the conclusion without knowing all that is like taking it totally out of context. So firstly if you are going to try and interpret a research study, make sure you read the whole thing.
The second mistake I see a lot of people making, which is related to the first mistake, is that most people just regurgitate what someone else said about a research study. And guess what? That person probably only read the conclusion.
So it’s really important when you are interpreting research studies to make sure you look at the whole study. Read the whole thing and get the context of how the study was put together. And how this study came about and what they were trying to achieve in the first place.
So let’s get back to my comment about a lot of the current research on stretching and flexibility is flawed. Now, let me explain that by giving you a bit of a story or an illustration. Imagine that you’re about to run onto the sports field and it doesn’t matter what sports. It could be soccer, football, baseball, basketball. It could be cycling or swimming. Just imagine you’re about to run onto the field and the coach says to you… “Hey, you should do three sets of sit-ups, three sets of push-ups and three sets of lunges before you run onto the field.” And you go, well why should I do that? And the coach says… “Well that’ll make you a better athlete and that will prevent injury.”
Well I don’t know about that. And I think anyone who’s got a little bit of knowledge about strength and conditioning or sports coaching will know that doing a few push-ups before you run under the sports field isn’t going to help. And if you did a study where you had one group who did those exercises before they ran onto the field and another group who didn’t. I can pretty much guarantee that the results you would get would show no significant difference between the two groups. And essentially that is what a lot of the studies on stretching and flexibility are doing. They take in two different groups. They’re getting one group to do a few stretches before they run onto the sports field.
So they’ll, for example, do a few hamstring stretches, do a few calf stretches, maybe a few quad stretches, and then go and play their sport. And then what the researchers will do, look at the two groups after they play their sport, they’ll compare performance. They will compare injury rates and so forth. Some of these studies are done over a short period of time, maybe only six weeks. Some are conducted over a longer period of time, like six or 12 months. But in the end what happens is that there’s no real significant difference between the two groups. So whether they stretched before exercise or they didn’t, there’s no particular benefit or no particular perceived benefit.
But the problem or the flaw comes because that’s not how you use stretching. You don’t just do a few stretches before you run onto the sports field and expect that you’re going to be a super athlete or bulletproof to injury. That’s NOT the way you use stretching.
So if that’s not the way you use stretching (and this is separate to a warm up of course; as part of a warm-up you do use stretching, but that’s not what we’re talking about here). We’re talking about the research studies that have been conducted on stretching and flexibility. And nine out of 10 of them follow this type of procedure. Two groups of people, a stretching group and a non-stretching group. Do a few stretches before you run on the field. See what the differences are after you play a sport.
So if that’s not how you use stretching, how do you use stretching? Well, as I explained in the article, you use stretching in exactly the same way as you use strength training. So for example, a coach, a strength coach would look at the athlete, look for weaknesses, look for imbalances. Look for areas where a specific strength is important to that person’s sport. And then they design a routine or strength routine to compensate for those weaknesses, those imbalances and so forth. And over the long term, 3 months, 6 months, 12 months. Those strength improvements will help the athlete.
And it’s exactly the same with stretching. The coach looks at the athlete, they look for weaknesses, they look for imbalances, and they look for areas where stretching or improved flexibility will help their sport. And then they design a stretching routine or a stretching program that the athlete uses to improve those weaknesses and imbalances. And over the long term, again, 3 months, 6 months, 12 months, hopefully those imbalances go away. Those weaknesses go away and therefore that translates into improved performance on the field and a reduction in injury.
So when I said that a lot of the research is flawed, I meant that the way the research is carried out is flawed. So this is unfortunate because it gives people the misconception that stretching is of no benefit at all. And that’s certainly not the case.
So I hope that’s cleared things up a little bit. I want to make one point before I finish up. And that is, I’m in no way against scientific research or scientific studies, they’re very valuable, but they have to be used in context. Or in proportion with all the other research and all the other anecdotal type evidence that can be gained.
So I hope that’s helped. I hope you’ve enjoyed the further explanation. What I will do is I’ll make sure I include a link to that original article somewhere on this page so you can go and read it if you want to. In the meantime, stay healthy, keep stretching and God bless. Bye for now.
What does the research say?
In an attempt to measure the benefits of stretching, researchers have tried to use stretching in the same way as the examples above. They have tried to measure the effects of doing a few stretches before playing sport, and when the results of their research suggest that no benefit was gained, they make the wrong assumption that stretching is not beneficial.
In fact, a few weeks ago one of my readers sent me an article titled; “Stop Stretching!” In it the author claims that “…research shows stretching has no value.”
These sorts of blanket statements are a miss-interpretation and a gross exaggeration of the research, and are very miss-leading as to what the research actually says.
Although the author only makes reference to one study, I can assume he’s referring to any number of studies that have been done over the last 10 to 15 years on the effects of stretching before exercise.
Now I’m the first to admit that stretching is no miracle activity. Stretching is just one part of a holistic health and wellness plan: An often neglected part, but all the same, just one part. So I do my best to keep a level-headed perspective of what stretching can and can’t do. So what has the research proved so far?
“Since the early 1980’s, stretching has been promoted as a method to prevent injury and improve athletic performance. Although research suggests that this may be true for regular stretching performed every day, an isolated act of stretching immediately before exercise likely has no effect on injury prevention and actually impairs performance in strength and power sports.”
“Improvements in force, power and running speed are noted following regular stretching, in marked contrast to acute stretches performed immediately prior to exercise, which tend to yield opposite effects, (though acute stretching is helpful in certain situations, particularly where the benefits of increased ROM outweigh the limits to force and power production).”
“Stretching immediately before exercise is deemed ineffective in preventing injuries and also reduces force and power by about 2% to 5%. Regular stretching over weeks yields opposite effects, increasing force and power by about 2% to 5% while improving running speed by about 0.06 second during a 50-yard dash.“
In other words: Doing a specific type of stretching, in a specific way, immediately before another specific activity, can have a negative effect on athletic performance.
NOT that “stretching has no value.” Anyone who makes a comment like this either doesn’t know how to interpret a research study (or maybe they’ve never even read the research and are just regurgitating what they’ve heard someone else say), or they have an ulterior motive.
What else do we know from the research?
“This study suggests that chronic static stretching exercises by themselves can improve specific exercise performances. It is possible that persons who are unable to participate in traditional strength training activities may be able to experience gains through stretching, which would allow them to transition into a more traditional exercise regimen.”
“Warm-up also appears to reduce the incidence and likelihood of sports-related musculoskeletal injuries. Improving flexibility through stretching is another important preparatory activity that has been advocated to improve physical performance. Maintaining good flexibility also aids in the prevention of injuries to the musculoskeletal system.“
Warning! Be very wary of anyone who tells you that doing a few stretches before your next game will make you sports injury bullet-proof or turn you into a super athlete. However, taking 5 minutes to do a few stretches both before and after each workout will improve your flexibility over the long term. And if you’re consistent, in a month or two you’ll find that you have a greater range of movement; you’ll feel more fluid and relaxed; you’ll be less susceptible to muscle strains and pulls; and you’ll be enjoying your sport more too.
A strength training comparison
By the time I got to university in 1990, I’d already developed a keen interest in the field of sports coaching and athletic training. I was at university studying health science in sport and exercise, and I’d eagerly devour any new research I could get my hands on about how to train athletes more efficiently and effectively.
As I read through the latest and most advanced training methods other coaches and researchers were using, I started to notice a number of research articles emerging about this new form of training called: Strength and Conditioning.
Now I know this may seem quite odd to anyone who has worked in the strength and conditioning industry for less than 20 years, but stick with me because as you read through the rest of this article you’ll start to see a lot of similarities between what was happening in the strength training industry 25 years ago, and what’s happening with stretching and flexibility today.
Previous to the mid 1980’s, the only people who did strength training, or lifted weights, were body builders, and the thought of any other athlete lifting weights was ridiculous.
There were a few exceptions, but for the most part the accepted method of training at the time was: Specificity! In other words; if you were a runner, you ran. The thought of lifting weights or performing other non-running activities was just plain crazy.
As athletes and coaches started to experiment with different types of strength training a vicious debate developed about the proposed benefits of such an activity. One month there would be articles praising the benefits of this new revolutionary training method, explaining how athletes would now be able to run faster, jump higher and do away with sports injury.
Then the next month another article would come out exposing strength training as a waste of time; an activity that did more harm than good, and would only serve to slow athletes down and cause more injuries, not less.
Does this sound familiar? Are you hearing similar comments regarding stretching and flexibility training? So what happened with strength training?
Over time, coaches, athletes and researchers discovered how to use strength training for the greatest benefit to the athlete. They discovered what worked and what didn’t and kept modifying their training until they came up with guidelines for effective strength training.
So… How does stretching prevent injury?
If doing a few stretches before playing your sport isn’t going to help; how do you use flexibility training in a way that will prevent injuries and make you a better athlete?
The short answer: In exactly the same way as you would use a strength training program.
When designing a strength training program, the trainer first assesses the player for weaknesses, imbalances and areas of their game or performance that need improvement. The trainer then designs a program that works to improve these areas, and over the long term, these strength improvements translate into improved athletic performance and a greater resilience to injury.
And the same applies to flexibility training.
When designing a flexibility training program, the same approach is taken. The player is first assessed for weaknesses, imbalances and areas of their game or performance where flexibility is important and needs to be improved. The trainer then designs a program that aims to improve these areas, and the program is applied over the long term. As the player’s flexibility improves, so does their athletic performance and their resilience to injury.
Stretching is not a quick fix
Remember, stretching is not a quick fix. The benefits of proper stretching are only attained when flexibility training is applied professionally and diligently over an extended period of time. And there are no magic stretches. Doing one or two stretches every now and again isn’t going to help. And doing the same stretches over and over again isn’t going to help either.
While the recommendations on this page are a good starting point, you'll get a lot more benefit when you add the right stretches to your training program. With the Ultimate Guide to Stretching & Flexibility (Handbook, DVD & CD-ROM) you'll...
You'll get 135 clear photographs and 44 video demonstrations of unique stretches for every major muscle groups in your body. Plus, the DVD includes 3 customized sets of stretches (8 minutes each) for the Upper Body; the Lower Body; and the Neck, Back & Core. And the Handbook will show you, step-by-step, how to perform each stretch correctly and safely. Plus, you'll also learn the 7 critical rules for safe stretching; the benefits of flexibility; and how to stretch properly.
If you want to improve your flexibility so you can to train harder, race faster, recover quicker and move better, check out the Ultimate Guide to Stretching & Flexibility for yourself.
Research and References
- Walker, B. (2011) The Anatomy of Stretching, 2nd Edition (ISBN: 978-1583943717)
- Alter, M. (2004) Science of Flexibility, 3rd Edition (ISBN: 978-0736048989)
- Pereles, D. Roth, A. Thompson, D. (2010) A Large, Randomized, Prospective Study of the Impact of a Pre-Run Stretch on the Risk of Injury in Teenage and Older Runners. CAQ Sports Medicine, USATF, Simon Fraser University.
- Nuckols, G. (2018) When To Trust Research Findings. Stronger by Science.
- Kokkonen, J. Nelson, A. Eldredge, C. Winchester, J. (2007) Chronic Static Stretching Improves Exercise Performance. Medicine & Science in Sports & Exercise. Volume 39 – Issue 10 – pp 1825-1831.
- Shrier, I. (2005) When and Whom to Stretch? Gauging the Benefits and Drawbacks for Individual Patients. The Physician and Sportsmedicine. 33(3):22-6.
- Sexton, P. Chambers, J. (2006) The Importance of Flexibility for Functional Range of Motion. International Journal of Athletic Therapy and Training, 11, 3, 13-17.
- Caplan, N. Rogers, R. Parr, M. Hayes, P. (2009) The Effect of Proprioceptive Neuromuscular Facilitation and Static Stretch Training on Running Mechanics. Journal of Strength and Conditioning Research, 1175-1180.
- Shellock, F, Prentice, W. (1985) Warming-up and stretching for improved physical performance and prevention of sports-related injuries. Sports Medicine, 2(4):267-78.
- Fradkin, A. Zazryn, T. Smoliga, J. (2010) Effects of warming-up on physical performance: a systematic review with meta-analysis. Journal of Strength and Conditioning Research, 24(1):140-8.
About the Author: Brad Walker is often referred to as the "Stretch Coach" and has even been called the Stretching Guru. Magazines such as Runners World, Bicycling, Triathlete, Swimming & Fitness, and Triathlon Sports have all featured his work. Amazon (author page) has listed his books on five Best-Seller lists. Google cites over 100,000 references to him and his work on the internet. And satisfied customers from 122 countries have sent 1,000's of verified customer reviews. If you want to know about stretching, flexibility or sports injury management, Brad Walker is the go-to-guy.
Disclaimer: The health and fitness information presented on this website is intended as an educational resource and is not intended as a substitute for proper medical advice. Please consult your physician or physical therapist before performing any of the exercises described on this website, particularly if you are pregnant, elderly or have any chronic or recurring muscle or joint pain.