Stretching the limit of injury prevention - a physio 'how-to' guide to stretching

Introduction

Stretching, or the forceful lengthening or a muscle in order to reduce its tightness, has been around for thousands of years and is hardwired into the makeup of humans and animals alike.

The first thing most people do in the morning (after pressing snooze on the alarm 5 times) is to let out a great yawn and stretch out all the muscles that have been dormant while you sleep.

It is so instinctual that even the family dog and cat will do it!

Stretching as an injury prevention strategy dates way back to the ancient Greek and Roman armies who would stretch before battle to improve their flexibility in order to avoid winding up on the wrong end of a blade.

In more recent years it has utilised by modern day warriors as they wage war on their chosen battle field, whether it be a football oval, soccer pitch, netball court etc.

Regardless of the age, skill level or activity, stretching has embedded itself as an integral component of warm up and cool down routines around the world in an attempt to optimise performance and reduce injury.

But does it actually work?

Before we address this controversial question, let’s have a look at a few different types of stretching and their supposed benefits…

Types of stretches

1. Static stretching

Static stretching is arguably the most common form of stretching in the general community. It involves moving into and holding a position that stretches a muscle, resulting in an improved length and greater flexibility.

The optimal amount of time to hold a stretch is approximately 30 seconds; too little will not allow time for changes to occur in the muscle and too long can actually reduce muscle performance and increase the likelihood of injury.

2. Ballistic stretching

This ‘old school’ method of stretching involves moving to the end of a muscle’s limit and then performing small bouncing movements to try and get further.

This is often associated with a reflexive muscle tensing in response to the sudden stretch and can result in an injury before you even get onto the field!

3. Dynamic stretching

Dynamic stretching is gaining more and more popularity within the sporting world because it improves flexibility and, unlike static stretching, hasn’t been proven to significantly reduce performance.

Dynamic stretching is the rhythmic movement through a joint’s range of motion, gently pushing into the limits of a muscle’s flexibility.

It is generally performed 10 times, gradually increasing the speed and amount of movement.

4. Proprioceptive neuromuscular facilitation (PNF) stretching

Proprioceptive neuromuscular facilitation stretching is the most effective of the four at improving muscle length.

It is usually done with a partner and involves contracting the muscle for 5-6 seconds before relaxing and performing a static stretch.

This can be repeated multiple times.

However, like static stretching, it has been shown to decrease muscle strength and is not recommended before performing explosive sports.

The big question

So, if 3 of these 4 stretches have been shown to reduce performance or increase the risk of injury and the jury is still out on the other, why is stretching still so widely used as an injury prevention strategy?

The answer is quite simple.

If you have tight muscles and restricted range of motion, you are more likely to sustain an injury.

On the flip side, if your muscles are too loose and not performing as well as they should be, you are again more susceptible to an injury. The classic ‘catch 22’.

If by this point you’re feeling exasperated and wondering if there is anything you can do to before exercising to limber up and reduce the risk of injury, don’t despair!

The solution: sport-specific warm-up routines.

The solution

Sport specific warmups are a vital component of an effective pre-game ritual and is actually something your team probably already does.

They involve a combination of static and dynamic stretching, aerobic work (i.e. running), jumping and balance exercises, usually integrated into sport-related drills.

The effect of the sport specific warm-up is ‘preconditioned muscles’, which is the body’s equivalent of warming up the engine of your car.

If you jump into your car on a cold winter’s morning, start it up and try to take off Fast and the Furious style, there’s a good chance you’re going to blow something up.

As you progress through the warm-up (or run your engine for a while), your muscle fibres (engine pistons) start firing more efficiently which improves your coordination and response time, allowing you to take off quicker, jump higher, dodge more opponents and perform at your peak.

The warm-up also increases the temperature of your muscles by 1 degree which may not seem like much, but this tiny change reduces the viscosity of the fluid in your muscles allowing it to stretch further before tearing.

So, why stretch?

Don’t get me wrong, I’m not trying to say that stretching is a complete waste of time because it does have its benefits and it is an integral component in many of my physiotherapy treatments.

A lot of people who come to see me have pain or reduced movement due to an ‘active restriction’, which is a fancy way of saying that the muscles are tensing up too much and have shortened from working overtime.

In these scenarios a combination of regular stretching and release work through the muscle throughout the day is an extremely effective way of calming it down and allowing it to work normally again.

Stretching also feels good, which is reason enough to do it in my books.

After a big work out or intense training session, the muscles that have been working hard will be tense and full of lactic acid so going through and stretching all the major muscle groups will help relax them off and remove some of the waste products.

The take home message

According to the evidence, stretching before activity doesn’t have much going for it in terms of injury prevention and has been shown to reduce muscle performance.

On the same token however, going into the game with tight muscles with also predispose you to an injury.

The best way to combat this is to perform a sports-specific warm up routine before the game involving minimal static stretching and do a lot of stretching and muscle release (massage, foam roller etc) during the week so your muscles are at an optimal length going into game day to give yourself the best chance of being victorious in your battles!

References

• Sampaio, F., Rangel, L., Mota, H., Morales, A., Costa, L., Coelho, G., Ribeiro, B. (2014). The Effects of Passive Stretching on Muscle Power Performance, Journal of Exercise Physiologists. 17(6). 81-89.
• Lewis, J. (2014). A Systematic Literature Review of the Relationship Between Stretching and Athletic Injury Prevention, Orthopaedic Nursing. 33(6). 312-320