What should you do at the start and end of every exercise routine to prevent injury? Your answer is probably “stretching” – and most people would say the same thing. Unfortunately, stretching doesn’t do what you think it does.
Large scale systematic reviews have looked at evidence from numerous trials over the years and have found that stretching is not an effective way of reducing injury. In an exhaustive comparison between stretching, strength training and balance training, stretching did little to prevent injury while strength training reduced sports injuries by a third and almost halved overuse injuries.
When you think about it, strength training’s effectiveness is to be expected. The load that you put through your muscles, joints and tendons when you lift weights is far above anything you encounter in day to day life or even most sports and activities. The more load your body can handle, the less likely it is to be injured.
Stretching can reduce performance
Not only does stretching not prevent injury to any significant degree, it can actually reduce performance in certain activities.
To understand why this happens, first you need to know about the length-tension relationship. Movement occurs by muscles lengthening and contracting, but if a muscle is lengthened too much it can reduce its ability to contract. Static stretching – where you hold a stretch from anywhere between 30 to 60 seconds – can, in the short term, “over-lengthen” your muscles, causing a sub-optimal length-tension relationship.
The better choice for a pre-exercise activity is 10-15 minutes of cardio to get your blood pumping or low threshold versions of whatever movements you’re going to be making. For example, if you’re about to do squats with heavy weights, first go through the movement with light or no weights to make sure all the muscles you need are activated.
If you’re running, a simple jog on the spot, lifting your knees high and kicking your heels to your bum will suffice. Running doesn’t require any large ranges of motion, so there’s really no sense in stretching. For sports like football or rugby, practice your jumping and landing technique and perform twisting and turning motions to prepare your body for the greater ranges of motions required.
Want to be more flexible? Strength training’s still better
Another reason people stretch is to improve flexibility but, again, strength training still beats it. There’s a type of strength training called eccentric training, which focuses on lengthening the muscle under load to improve its performance as it elongates. If you think of a bicep curl, eccentric training would focus on the downward motion rather than the upward contraction.
Why just improve your flexibility with stretching when eccentric training can improve your flexibility and your strength at the same time?
Times when stretching is useful
One area where stretching can be beneficial is in activities with intense shoulder rotation, such as tennis, cricket or baseball. As power in these sports is generated through the swing of the arm, it’s important for the shoulder to be able to move comfortably through its entire range of motion.
Stretching can also help reduce muscle soreness after exercising (thought not as effectively as gentle use of a cycling or cross trainer machine) and certainly has an important role in the recovery programmes we prescribe for injuries. The point is not that stretching is useless, just that many people use it the wrong way and for the wrong reasons.
You don’t have to stop stretching
Despite all the above, if stretching is a part of your routine, I don’t actually suggest that you stop. Stretching may not help, but it doesn’t hurt either. In fact, it feels great, and if it’s a part of your routine, then suddenly taking away the psychological boost that it gives you could have adverse effects. Unless you’re doing an activity where it could reduce your performance, you can stretch as much as you like.
What I will say is that, if you decide to keep stretching, make sure that it’s not taking time away from things that are proven to reduce your risk of injury, such as warm ups and strength training.
Of course, this is all general advice. Every body is unique and if you want to make the most of yours, you need to understand its strengths and its weaknesses. If you have any questions, feel free to email me at firstname.lastname@example.org or call 020 7937 1628 to book an appointment with us today.
David Wynne BSc (Physio) MSc (Sports and Exercise Medicine) MCSP MHCP
Musculoskeletal and Sports Physiotherapist, Research Lead at West London Physiotherapy
For any other questions regarding this topic please do not hesitate to contact West London Physio on 0207 937 1628 or email David at email@example.com