What Causes Running Injuries?

200363983-001By kind permission of Andy Dubois www.mile27.com.au

Running injuries are so common , more than 50% of runners suffer one every year. Why?

Is it because they

a) Increased their distance too quickly
b) Increased their intensity too quickly
c) Didn’t stretch before running
d) Didn’t stretch after running
e) Were wearing cushioned supportive running shoes
f) Weren’t wearing supportive running shoes
g) None of the above

 

If you answered g) none of the above you are correct.

Running injuries occur because there is some form of biomechanical imbalance which when subjected to a repetitive load causes a part of the body to break down.

Doesn’t increasing your mileage or intensity too quickly cause injuries?

If you suddenly doubled your mileage and your left knee complained you would attribute that to the increased mileage. But if increased mileage was the cause of the injury why didn’t the right knee complain as well?

If increasing distance or intensity too quickly was the cause of the injury then you would expect both your right and left knee to suffer the injury. But this rarely happens.
When only one side of the body is injured the cause is some form of biomechanical problem that affects one side and not the other.

I am not saying that doubling your mileage is a good idea, you should always increase mileage and intensity gradually to give your body time to adjust. What I am saying is that the cause of the injury is not running too much , it’s the biomechanical problem that is waiting to make itself known as soon as you do too much.

I am also not saying that if you were biomechanically perfect you could run as much as you like. As you increased your running either both sides of your body would break down or overall fatigue would force you to take a few days off.

Does stretching before or after a run decrease your risk of injury?

There is no research at all to show that static stretching before a run will reduce your risk of injury. In fact there is some research that shows it will more likely increase your chances of becoming injured.

The research on stretching after a workout or stretching in general is less clear. Maybe it helps maybe it doesn’t. The reason for this is that static stretching is an ineffective means of increasing the dynamic range of movement at a joint. Three dimensional dynamic stretching is far more effective method.

More flexible runners have been shown to be less economical so increasing range of movement for the sake of it isn’t recommended. Knowing where you lack range of movement and working at increasing both the range and elasticity of the muscles controlling that range is the key to improving your running and preventing injuries.

Do shoes affect your risk of injury?

Some people will suffer less injuries in barefoot or minimalist shoes, others will suffer more and will need more supportive shoes. Every persons foot is unique and what suits one foot won’t suit another.

The type of footwear used will affect the load placed on any biomechancial weaknesses in a positive or negative way so good choice of foot wear is important. Ideally seek advice from a podiatrist with a running background.

What kind of biomechanical imbalances can cause injuries?

When we think of imbalances we usually think of muscular imbalances i.e a muscle is weak, but there are many other imbalances that can occur

Structural imbalances

Our bones arent perfectly symmetrical. The left side of our body isnt exactly the same as our right. The amount of difference will determine how much of a compensation the body has to make to even things out. For many of us the body can cope pretty well with the minor asymmetries we have but others may need some kind of orthotic device to correct for a leg length difference or bony foot abnormalities.

Soft Tissue imbalances

Changes in muscle tension due to trigger points or areas of fascial tightness are complex topics that we dont fully understand yet but certainly affect how our body functions. Having a regular massage is a good way to reduce the affect of these on your body. Even self massage can be effective with a bit of practise.

Muscle Strength imbalances

For the body to function optimally a balance between both left and right, front and back, top and bottom, in and outside of our body is necessary. If the muscles on our back half (glutes and hamstrings) are weaker than the muscles of our front half (quads) then we have problems. Likewise if the deep stabilising muscles around the hip arent in balance with the strength of the outer muscles of the hip problems will also occur.

Unfortunately strengthening muscles isn’t as simple as many people will have you believe.

Just because your glute muscles are weak doesnt mean that any exercise you can find on the internet that works your glutes will strenghten your glutes for running. Muscles dont work in isolation and what happens at every other joint in your body affects the relative strength of the muscle you are trying to work. Since every body is different it doesn’t make sense that one exercise will be effective for everyone. Every person will respond differently to a particular exercise. Exercises need to be tailored to both running and the individual to be truly effective.

Muscle flexibility imbalances

Another reason that is very commonly given as to the cause of injuries is tight muscles. To fix this stretches are given and with any luck you’ll be back running, injury free. Unfortunately it is not as simple as that. For one the static stretching prescribed by many therapists and trainers don’t actually improve dynamic ranges of movement. It may help re-align scar tissue that occurred as a result of an injury and that might get you back running but it will never resolve why the muscle was tight in the first place.

If you have tight calves then you have them for a reason, to truly address a tight muscle you need to assess why that muscle is overworking and becoming tight in the first place. Simply stretching it wont resolve the cause of the problem.

A tight hamstring may be as a result of a weak glute muscle and weak abdominal muscles which force the hamstring to compensate. Stretching the hamstring isnt going to fix the weak glutes or abs.

How to prevent injuries?

The solution is to correct your biomechanics. Whilst no-one is ever perfect , the better your biomechanics the less chance of injury.

How to can you correct your biomechanics ?

Correcting biomechanics isn’t easy. First of all you need an assessment to determine any problem areas. Once these are identified exercises can be created that address any strength or flexibility deficits.

If you don’t have access to someone who can do that then the next best approach is to follow the guidelines outlined in the strength training for runners part 1 , part 2 and the dynamic stretching blogs. Identify any differences between left and right. Simply perform more repetitions on the weaker/ tighter side until both sides feel even.

This approach whilst certainly better than nothing is nowhere near as effective as having someone assess you and custom design your exercises.