What should you do before and after exercise to prevent injury? Your answer is probably “stretching” – and many people would say the same. Yet, stretching doesn’t do what you think.

Large studies have found that stretching is not generally effective at reducing injury. In a comparison between stretching, strength training and balance training, stretching did little to prevent injury. On the other hand strength training reduced sports injuries by a third and almost halved overuse injuries.

Strength training’s effectiveness should be expected. The load that you put through your muscles, joints and tendons when you lift weights is far more than 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 fail to prevent injury, it can also reduce performance in certain activities.

To understand how this happens, first you need to know about the length-tension relationship. Movement occurs when muscles lengthen and contract, 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.

The better 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 squat with heavy weights, first do the movement with light or no weights to make sure all the muscles you need are warm and activated.

If you’re running, jogging 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 sport specific technique such as landing and jumping, as well as twisting and turning

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 sports with lots of 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 and certainly has an important role in the recovery programmes we prescribe for injuries. The point is not that stretching isn’t helpful, just that people often use it the wrong way, for the wrong reasons.

You don’t have to stop stretching

If stretching is a part of your routine, we don’t actually suggest that you stop. Stretching may not help, but it doesn’t hurt either. It feels good, and if it’s a part of your routine, then suddenly taking away the psychological boost that it gives you could have adverse effects.

If you decide to keep stretching, make sure you’re still doing the things that reduce injury risk, such as warm ups and strength training.

Of course, this is general advice. You are unique and if you want to make the most of your body, you need to understand its strengths and its weaknesses. If you have any questions, feel free to email me at jack.mest@physiolondon.co.uk or call 0207 093 3499 to book an appointment with us today.

Jack Mest

Clinical Lead, Physiotherapy London