Stretching Doesn't Work...?

At least that's the sort of sentiment my Twitter feed has been full of this week. So, rather than trying to share my thoughts on stretching with only 140 characters, I thought it would make an interesting blog post...

Last year (2013) Danish researchers Lauersen et.al. published a meta analysis^? in BJSM, which has gone-on to gain some traction amongst the wider sporting community.

Here's the Abstract:

With a conclusion like that, I'm not surprised to hear many of those who have never really gotten on with stretching using this review to vindicate their often vocal anti-stretching standpoint.

Let's Take a Closer Look

Pretext

I've said it before; in the fitness industry we are often culprits of two mistakes:

1: Trying to polarise our stance on any given subject, and applying this across the board with our advice.

2: Reading research abstracts and jumping to conclusions, in lieu of reading and understanding the full text.

I do include myself in this... I think I'm getting better!

With that in mind, let's take a closer look at the review and understand a bit more about the data involved. There are some key details to consider that aren't addressed in the abstract.

Targeted Strength Training & Specific Outcomes

In this review, strength training was shown to reduce acute injuries down to one third, and overuse injuries down to one half. That's great. There's no arguing with that!

But, the question has to be: "what kind of strength training?" and "for which injuries?".

When you dig into the data pooled from the 25 studies used for this review, you can see that half of the studies using strength training as an intervention focused only on hamstring strengthening, and only looked at changes in hamstring injury occurrence, rather than overall rate of injury occurrence.

Understanding that different types of injury occur across the body through differing mechanisms; this type of specificity will fall short of telling us the full story about the efficacy of strengthening regimes.

Multiple Training Methods

Eleven studies included in this review investigated the efficacy of multi-faceted programs incorporating multiple training methods. Typically (with a few exceptions) these looked at occurrence rate of all injuries or lower limb injuries in general as their outcome measure.

This is where research gets really tough, as different types of exercise/method will be more or less effective in helping to prevent any given type of injury. The scope is just so wide!

Being specific about the measure (i.e. type of injury) allows us to look at the effect of a specific intervention. Take the Gilchrist et.al. paper for example, which was used as one of the sources for this particular review, in the 'Multi' category. In their study, they wanted to see whether a simple on-field alternative warm-up routine can reduce non-contact Anterior Cruciate Ligament (ACL) injuries in collegiate female soccer players.

Their warm-up protocol focused on neuromuscular control exercises. Neuromuscular control is an accepted factor in non-contact ACL injury. It was observed that non-contact ACL injury rate among athletes performing their warm-up was 3.3 times less than in the control group. The specificity of this link between intervention and measured outcome enables strong conclusions to be made.

In comparison, this meta-analysis leaves a number of question marks in my mind when we consider how specific exercises will help target specific types of injury. We need to appreciate the demands/risks of the sport each athlete is engaging in, their injury history, and create their program accordingly.

What About Stretching?

So, back to the title of this article... Many of the articles, tweets etc that ensued as a result of the publication of this meta-analysis were focused on the loose conclusion that "Stretching Doesn't Work" to prevent injury.

Of the 25 studies included in the review, only three specifically investigated the efficacy of stretching as a form of injury prevention.

In each of these 3 studies, the intervention was various forms of static stretching, rather than dynamic stretching pre-exercise. Thus it comes as no surprise to me that little benefit was experienced.

What to Make of All This?

Firstly, as ever, don't be too quick to jump on the bandwagon. Be smart: check out the source and its data, not just the headline or the abstract!

Have a healthy cynicism about anybody touting method x, y, or z as being the "best" or indeed "of no use" for the prevention of injury in general terms.

We should be probably be speaking instead in terms of specific injuries, and types of injury commonly sustained by specific types of athlete.

For Example:

• ITB Syndrome in Triathletes
• Groin Injuries in Soccer Players
• ACL injuries in Netball Players
• etc...

For Runners & Triathletes?

Firstly, none of the papers reviewed in this meta analysis were looking at a running or triathlon population specifically. This is important to remember.

We know that in runners and triathletes, many (not all) of the injuries we see are overuse in nature and often come as a result of muscular imbalance, poor stability, and inadequate strength-endurance in certain areas. These factors create compensatory movement patterns, muscle activity and postures. Some muscles increase in tone (get tighter) and others become positionally weak as posture changes.

As runners and triathletes, we engage in highly repetitive movement patterns. Unlike many of the multi-directional sport (soccer, basketball, etc...) athletes from the studies in this review. In my experience, we're more likely to build and reinforce overuse patterns and get 'tight' accordingly.

As an example of where daily habits become part of the picture, these imbalances are sometimes exacerbated by sitting for extended periods of time frequently.

Is stretching on it's own enough to fix/prevent this. Nope! But it's normally part of the big picture.

Muscles get 'tight' when they have a stimulus to do so. Perhaps it's protective, perhaps it's as a direct result of weakness or fatigue, or simply due to postural adaptation. Identifying these imbalances and dysfunctions is an important start, then correction usually combines strengthening, stretching, mobilising, improving neuromuscular control, movement pattern re-education etc...

In my opinion - and it does come down to opinion because the research isn't conclusive yet - a multi-faceted program based on demands for the sport is the way to go for any given athlete's injury prevention needs. Whoever is designing the program needs to understand the demands of the sport, common injury patterns associated, and of course the history of the specific athlete in question.