How A Running Biomechanics Screening Can Help Your Marathon Training

Marathon Training
(Image credit: PR)

Runners tend to only consider their risk of injury when they actually succumb to one, but as in all walks of life prevention is far better than cure. Of course it’s not possible to entirely injury-proof your body in any sport, but there are many things runners can do to reduce their risk of suffering from common problems like runner’s kneeshin splints and plantar fasciitis.

One is to keep a close eye on the amount you’re running to ensure you’re not increasing the distance or intensity too quickly, which is why closely following a training plan for a marathon is advisable. Another is to work on your strength and conditioning, especially in the lower body and core, to make sure your muscles can handle the pressure of regular running.

A third is to get a biomechanics screening to analyse your running style. The point of this isn’t to tell you why everything about the way you run is wrong and then try to overhaul it. Instead it can help identify any imbalances in your body and how some parts of it might be compensating for weaknesses in others – thereby exacerbating the imbalance. We went to PerformanceRx in London to get a screening from biomechanics coach Anthony Fletcher, and despite being regular runners with (touch wood) no major injury problems thus far, we still learned a lot about how our body moves on the run.

What do you look for at a biomechanics screening?

“What we’re looking for is asymmetries between similar structures in the body,” says Fletcher. “We look at the pelvis, the knees, the shoulders and the sides of the spine to see if there are any differences. And then we look for any compensations you’re using to correct them.”

Many runners develop compensations to deal with imbalances in their gait and find that they have no injury problems as a result of the body adjusting. However, imbalances that don’t cause any problems when you’re running 5K once or twice a week can lead to injuries when you increase your workload in preparation for a marathon.

“Imagine if a camel is already carrying 100kg, then you put an extra 10kg on it – that’s what breaks the camel’s back,” says Fletcher. “If you can find a way to reduce the existing load on the camel, you can then add more load onto it. You want to negate the compensations the body is dealing with before you take on a huge programme like training for a marathon.”

Can common running injuries like achilles tendinopathy and runner’s knee be caused by these imbalances?

“Absolutely, especially if it’s one-sided,” says Fletcher. “Very rarely do you get runner’s knee on both knees at the same time. This demonstrates there’s something not right in the loading between left and right – there’s something compensating.”

What happens at a biomechanics screening?

In our screening Fletcher checked the soles of our running shoes to see if one was worn more in certain areas, so it’s worth bringing a pair you’ve run a couple of hundred kilometres in. We then moved on to some mobility tests, before heading to the treadmill to run for ten minutes at a few different paces.

Fletcher could then tell us what that approach revealed. “What we found today is that you have a slightly longer left leg. This wasn’t something your parents gave you, that’s something you’ve created yourself, through something in your lifestyle or work. What that’s done is create a lack of mobility in your sciatic nerve, which reduces your hamstring mobility. You have 30° of hip flexion where your hamstring should be at about 70 to 80° for a runner. That presented in your gait as well, with a quicker, shorter stride.”

What should you do to fix these imbalances?

Naturally the exercises you do to counter any compensations in the body vary according to the compensation. We were given two exercises to do to create more mobility in our sciatic nerve, but – and here’s an illustration of the value of seeing an expert – we weren’t told to stretch our hamstrings, which would have been our natural reaction to tight hamstrings.

What you won’t get from a biomechanics screening is a whole load of adjustments to make to your running style at once in an attempt to create “perfect” form.

“The common mistake with a lot of people is that they think they are wrong in how they move and how they do things, when actually when you do something more often you become more efficient at it,” says Fletcher. "No-one told Eliud Kipchoge how to run, he just did it. You become better at running from doing it. But what you can do is work on your intrinsic mechanics to improve your efficiency and decrease your load between left and right, making it more symmetrical.”

When should you get a biomechanics screening?

“The ideal time is at the beginning of a training plan,” says Fletcher. “Then as you increase your running workload you’re also mechanically working more and more efficiently.”

However, in the real world most people will probably only consider a screening once they’ve already succumbed to injury. At this point it’s obviously less about prevention, and more about identifying the underlying cause of a problem.

“A lot of people feel injuries when they ramp up their volume or load,” says Fletcher. “Ideally you’d have prevented this from the beginning, but when you do feel something, a biomechanics screening can tell you why that particular one side of the body is aching. We try to work out the reasons why, rather than just bandaging the problem.”

How much does a biomechanics screening cost?

It costs £150 for a screening with Fletcher, which covers the assessment plus an exercise plan to work on any imbalances in your body. If you are training for a big event like a marathon and want to add some speedwork to your running schedule, Fletcher also runs the Onetrack Run Club – a free weekly track session on Monday nights at the Duke of York Square track in Chelsea in London.

If you’re not London-based, simply search online for biomechanics screenings in your area and you should find options easily.

Nick Harris-Fry
Senior writer

Nick Harris-Fry is a journalist who has been covering health and fitness since 2015. Nick is an avid runner, covering 70-110km a week, which gives him ample opportunity to test a wide range of running shoes and running gear. He is also the chief tester for fitness trackers and running watches, treadmills and exercise bikes, and workout headphones.