A Familiar Story
Regularly I meet new coaching clients who suffer from long-term running injuries. Their frustrating story often goes something like:
‘I take time off running, get regular treatment, do my rehab exercises, then gradually reintroduce running – only for the injury to come back.’
No doubt, to many this will sound like a familiar pattern!
It saddens me how frequently I hear runners say that, having been treated for long-term overuse injuries, and having gone through failed reintroductions to running, still nobody has ever looked at how they are running. It happens more than you’d like to think…
Running is one of the most cyclical, repetitive, high load movement patterns we put our bodies through. Where there’s an overuse injury caused by running, especially when the injury returns upon reintroduction to running after adequate rest, there is most likely a fundamental biomechanical dysfunction or technique flaw.
The following quote seems to fit quite well here in the context of injurious running biomechanics:
“The definition of insanity is doing the same thing over and over and expecting different results.”
Often misattributed to Albert Einstein, but possibly first coined in the Basic Text of Narcotics Anonymous (a bit of useless information for you!).
Put simply. In my experience, runners can do their rehab exercises at great lengths and get stronger / become more flexible / improve control, but if they return to running with the same technique that caused the overuse injury in the first place, they’re probably going to end up injured again.
Of course, every case is different. Some athletes will react well to rest and strengthening alone, for example. Others however will need to make fundamental changes to form to avoid a similar injury outcome when running is reintroduced to their programme.
Issues With Treadmill Based Analysis
I hold a strong belief that treadmill based gait analysis is redundant when it comes to authentically assessing running and walking gait. For the last couple of years I’ve insisted that all assessment I do are outdoor based. We are runners – we run outdoors.
Frequently the point is made that Jones and Doust (1996) shows us that adding 1% elevation to the treadmill most accurately reflects the energetic cost of outdoor running. This is true in terms of running efficiency from a metabolic point of view, as the slight elevation makes up for the wind-resistance experienced when running outdoors.
However, this doesn’t take into account the change in movement patterns experienced when the treadmill belt does the propulsive work for you.
This is well explained by Graeme Turner in his post Don’t Become a Treadmill Addict. On a treadmill at 1% elevation, you may be using the same amount of effort as outdoors – but you’re most likely moving completely differently in doing so.
Realistically speaking, having a treadmill in a sports injury clinic is clearly a good thing though. It enables the therapist to cast a cursory eye over running form in general terms. Treadmills are also particularly useful as a way to reintroduce loading in a more sterile, controlled clinical environment. I’d rather an athlete’s running was looked at on a treadmill than not at all!
As a simple example of what I mean – it’s certainly not uncommon for me to receive referral letters from other professionals stating something like: “Watching Client X on the treadmill, she runs with a forefoot striking pattern…”.
Yet when videoed running outdoors the runner displays a typical heel striking, over striding gait pattern.
As with all things running technique related, the way in which athletes adapt their gait patterns to run on the treadmill are entirely subject specific, as described by Nigg et. al. (1995). Changes in posture, cadence, strike pattern, upper body motion etc… are all fairly common when comparing an athlete running on a treadmill versus outdoor at the same pace. Some runners will show no significant change across the two surfaces, in some athletes the changes will be obvious. That’s what makes our job as coaches and therapists interesting!
Factoring In Fatigue
We all run with better form when we’re fresh, at the beginning of a session or race. Intuitively, most of us will have felt that our running form begins to deteriorate pretty quickly with the onset of fatigue. Various studies have looked at this, including this recent research by Koblbauer et.al. (2013) who set out to observe changes in running form with the onset of fatigue, and the relationship to ‘core endurance‘.
Craig Payne and Dr. Andy Franklyn-Miller both provide interesting commentary on this recent piece of research via their respective blog post and newsletter. Particularly interesting are these two observations:
- Significantly increased trunk inclination and increased ankle eversion peak angles when the runners were fatigued.
- The observation that ‘participants who displayed better core endurance exhibited larger trunk kinematic changes when fatigued‘. Core endurance had been tested using traditional core exercises such as side planks and lumbar extensions.
In the context of gait analysis, I feel it is very important that once an athlete is at a point in their rehab where they can begin to push their running to the point of fatigue – we as coaches and therapists need to assess how their movement patterns degrade with fatigue. We know that this is where underlying dysfunctions will come to the fore, and increase overuse injury risk factors.
Once we observe how the individual athlete’s form changes under fatigue, we’ll have a much better idea of what to strengthen, control and work on in general!