Gait analysis with 3D infra-red cameras

There are thousands of products to help, from pressure socks and knee straps to masai warrior shoes and gravity-defying treadmills.

Yet is there any evidence about what works? Welsh international runner Jessica Leitch was three-quarters of the way through an engineering degree at Oxford University when she discovered the data linking biomechanics — the way your bones and joints move — to running injuries.

She said: “There are several biomechanical measurements that are linked to common running injuries. For example, too much inward movement at the hip is linked to knee injuries.”

Everyone runs differently — Mo Farah lollops like an antelope, while Paula Radcliffe's characteristic head-bobbing never held her back.

Dr Leitch said: “I do not believe there is a correct way to run. There are lots of strong beliefs about it — that you should run this way or that way. There is no evidence about that. My focus is on injury, not performance.”

She added: “Fifty per cent of runners become injured each year. Unusual patterns in a runner's biomechanics can cause stress on joints, bones and soft tissue. The key to injury-free running is to identify and correct these before it is too late.”

Dr Leitch is so enthusiastic about the issue that she has set up the UK's first 3D biomechanics centre to analyse runners' gait and interpret the findings so any problems can be corrected by exercise.

A physiotherapist will join the company soon, after training at one of the few other clinics in the world to offer the analysis.

The clinic in Calgary, run by Professor Reed Ferber, created software comparing images of injured and uninjured runners — using the camera system being used in Dr Leitch’s Oxford research lab.

The Vicon cameras were developed by Dr Julian Morris, another former Oxford engineering department researcher, who founded Oxford Metrics in 1984 as a spin-off from Oxford Instruments.

OMG's ‘motion capture’ systems, with software to interpret the movement of reflective markers, are now used in computer animations for Hollywood movies, as well as helping disabled children at the Nuffield Orthopaedic Centre (NOC) in Headington.

Dr Leitch's ‘gait analysis’ service was launched two years ago at the NOC by Olympic runner Jo Pavey, who discovered why she had suffered two stress fractures and was advised how to prevent future injury.

Now investment from a new fund targeting Oxford high-tech start-ups has allowed Dr Leitch to set up a university spin-out company called Run3D, based at the Roger Bannister running track in Iffley Road.

Using three Vicon infra-red cameras and Prof Ferber's software, she can do a full assessment in two hours.

‘Gait analysis’ is offered by everyone from sports shops to private gyms, but her approach is very different.

She said: “They all rely on videoing people, but that is very subjective and not sensitive enough to detect the subtle abnormalities that can lead to injury. We measure a runner’s joint angles in the three planes of human motion. The results are then compared to a biomechanical database. It is a rigorous approach.”

Infrared waves from the cameras are reflected off the markers and re-captured.

The 3D position of each marker is calculated 200 times a second to show the runner's 3D joint angles at the pelvis, hips, knees and ankles. Each angle is plotted on a graph to identify variables associated with injury.

She says runners often baulk at the £295 cost, so Run3D is targeting triathletes, who already spend thousands on bikes and other equipment.

"We are planning to develop an analysis for cyclists as well. If we can get Bradley Wiggins, say, and analyse the way he rides, that would be great."

She has also demonstrated the system to coaches at Oxford United football club.

“In the long-term, the plan is to put the players through pre-season and post-season analysis. If you can identify a player who needs to be taken off after 50 minutes because they are at risk of injury, that is a big issue because they are paying so much for their athletes.”

As for Dr Leitch’s own running, she discovered the problem was her feet. Instead of landing on her mid-foot, which was causing injuries, she trained herself to land nearer to her heel.

“I had to strengthen my ankle muscles and I did it slowly, but it has worked. When I run, I think about the science and so much of the time the issue has to be biomechanical, because people get the same injuries.

“What makes one person only able to run 20 miles a week before they get injured, while another can run 80 miles?

“If you can change things so people don't get injured, they will not give up, and if you can encourage people to keep going, that has to be good.”

Now 30, she is second in the Oxford Mail Cross Country League, beaten only by her fiance, David Bruce, a doctor at the John Radcliffe Hospital, who is a co-director of Run 3D.