Calgary International Running Symposium

By AAPSM on 9th of October 2014 at 1:33pm | Share on Facebook
www.aapsm.org.au / articles / news / calgary-international-running-symposium

Chris Bishop In August 2014, I was fortunate to represent the Australasian Academy of Podiatric Sports Medicine (AAPSM) at the 2014 Calgary International Running Symposium. This was no ordinary symposium. 11 Keynotes. 35 presentations. Invite only podium presentations. 60 posters. On face value, a standard boutique conference. Yet behind the layers of scientific content, we were all here for one purpose; to honour the retirement of Dr Benno Nigg.

News

Benno Nigg has been a colossus of Biomechanics research for the best part of the last 40 years. Born in Switzerland, Benno studied Nuclear Physics at the ETH Zurich (Switzerland). In 1971, he started his carreer in Biomechanics. In 1976, he became the Director of the Biomechanics Laboratory at the ETH Zurich. In 1981 Dr. Nigg accepted an invitation to move to the University of Calgary, where he founded and developed the Human Performance Laboratory, a multi-disciplinary Research Center concentrating on the study of the human body and its locomotion. Currently, this research center has about 180 co-workers, working with micro- and macroscopic approaches on the understanding of movement, exercise and sport. Benno’s research concentrates on human locomotion with a large emphasis on mobility and longevity and its application to movement related products such as orthoses, shoe insoles, sport shoes, surfaces and sport equipment. What I learnt from the few days in Calgary was over and above his ground-breaking research, it was the lessons he had taught to the students he had taught, his ability to collaborate with like-minded researchers and call them friends, and his desire to advance the profession that make Benno such a loved and treasured member of the International Biomechanics community. It truly was a pleasure to be part of the experience.

So what can we take from such a world-class symposium in Calgary? A lot but I’ll do my best to sum-up the most important take-home messages.

 

Running injuries

The elephant in the room…what is an injury? Until we obtain consensus in the literature on how to define an injury, it remains difficult to compare between studies and populations. Key considerations in understanding injury were well presented by Jack Taunton:

·         Exposure – does increased exposure to activity increase our risk?

·         Rehabilitation – does inappropriate and/or a lack of rehabilitation from a previous injury increase risk of recurrence

·         How do we classify injury? Acute vs. repetitive vs. chronic

·         Genetic pre-disposition – implications for genetic testing in the clinic

·         Co-ordination variability – individuals have an array of movement patterns. Injury risk may be lowered if you change or vary up how load enters your body by allowing more movement patterns to be accounted for. Varying input signals by means of parallel shoe choice or changes in running surface/terrain, change in training volume and intensity.

 

Training errors

There was a huge amount of discussion devoted to the role of training errors - the number one cause of running injuries is and always will be, training errors!Firstly, Prof Joseph Hamill from U Mass in Boston clearly identified a role for footwear in reducing training errors. The concept of targeted shoes for targeted training has scientific merit, yet it is questionable whether the research provides the evidence of the benefit of different shoes during different tasks, or to inverse that, what requirements different training tasks have from footwear. Likewise, how we can use changes in training to manage load. This was also related to footwear choice, as different shoes will not change the amount of load entering your body but will load different tissues in different ways in different people.This was reinforced by the Injury Discussion Panel who identified four key shortcomings in our understanding of running injuries:

1.      Risk-factor studies - Research needs to be designed focusing on training. Jack Taunton from Fortius in Vancouver was very strong on this, identifying an increase in mileage > 10% each week will likely result in injury. Likewise, considerations in terrain, strength/flexibility, shoes and gender are required.

2.      Time-varying variables - Not many variables are fixed

3.      Collaborative research - Ensure we have the most experienced team with as much experience from different professionals as possible. Reed Ferber from the Running Injury Clinic in Calgary was adamant that the future is in large datasets that are a product of collaborations from research centers around the world.

4.      Clinical studies – Need to ensure we have large populations and appropriately powered research in the field. To quote Reed Ferber…”we need to tag them like wildlife. Mobile-monitoring allows us to understand real-world effect.”

 

Product design

Such a large focus of the symposium was on product design and development, largely footwear. So what was the consensus of what shoe companies should be focusing on? Well according to William Van Mechelen:

·         Customisation

·         Comfort (more about this later) and the role of cushioning. Evidence suggests a small but real (2-4%) increase in performance as a result of cushioning.

·         In-shoe foot movement – there is more to life than inversion and eversion, and it is certainly not appropriate to be assessing movement with markers on the shoe  shoes need to assist the foot, not be a hindrance

·         Design principles – what effects flex groove placement, torsional stability, heel counters etc) have on shoe function.Factors such as shoe comfort and cushioning properties (0.7%), bending stiffness (1%) etc. can all individually increase your running performance if the shoe matches your running characteristics

·         Shoe mass and relationship to economy – Ned Frederick claims a 1% change in running economy per 100g of a shoe. Martin (1985) claimed it was 7 x more costly to carry 1kg on the foot than on the trunk. However, before we get ahead of ourselves, Martyn Shorten summed it up best… that in a world searching for reduction in mass of footwear, any reduction must not compromise requirements like cushioning.

 

We were also fortunate enough to have access to representatives from the footwear industry as a panel...this is my take:

·         To further enhance and develop footwear, we require cutting-edge innovation. Looking at biomechanics alone is not the answer.

·         “We must gather knowledge, not data. 50% of research data collected is irrelevant”

Matthew Nurse, NIKE

·         “Cushioning properties of shoes need to change for different foot types”.

Jason Cheung, LiNing

·         “We must understand the importance of material design over and above standard kinematic and kinetic measures, and how materials influence movement.”

Nishiwaki, ASICS Corp.

 

Given the wide ranges available, I think product can be summed up in two important points:

1.      It’s the role of the clinician/retail representative to determine where does each runner fit in the continuum of footwear choice?

2.      As consumers we are spoilt for choice but at the end of the day, all shoes fit someone.

 

The benefits of running

John Bertram from the University of Calgary got us all thinking when he started with these two statements:

1.      Running is well described but not well understood

2.      The phenomenon of running is often confused with the mechanisms that produce it

Eric Mueller went a step further to identify what the goals of training should be:

1.      Optimization of movement patters

2.      Reducing running injury risk by changing wrong movement patterns

According to Eric, a runner’s biggest challenge is to leave stable but wrong movement patterns. In order to do this, a runner needs enhanced variability of movement at a microscopic level. This ensures structures can adapt to different reactive phenomenon. Variation in input signals to the body seems to be the key.

 

Representation of lab studies in the field

Martyn Shorten identified a clear disconnect between the laboratory and theory and/or reality. Martyn identified a number of key issues, but the three most important things I took away from his talks were:

1.      At the Boston Marathon in 2013, 65% of runners ran slower than 3.5 ms-1. Of these runners, 90% were rearfoot strikers. As speed increased above 3.5 ms-1, still only 25% were forefoot strikers. Not only was rearfoot striking the most common footfall pattern of choice, but most people train and run at speeds less than that seen in laboratory studies (normal range = 4.0 – 5.0 ms-1).

2.      Based on the data obtained from his online surveys, there is a 64% mismatch between self-observed strike patterns and actual observed foot strikes. Of those who claimed they were forefoot (15.7%), only 2.1% were true forefoot strikers. Of those who claimed they were midfoot strikers (43.4%), only 2.4% were actually midfoot strikers. Only 40.9% of responders claimed they were rearfoot strikers, whereas in reality, 95.6% of respondents were observed to have a rearfoot strike pattern when running. This data identifies that in non-heel strikers, there is in-fact a 93% mismatch between reported and observed heel strike patterns. This is best summarized by a quote from Professor Peter Cavanagh:

“Heel striking is a socially acquired disease that runners are scared to admit too.”

3.      Their may in fact be a new gait pattern called “grounded running”. Where it is traditionally thought that running has a float phase and no period of double support, Martyn showed evidence at transition speeds (2.0ms-1 is accepted as the transition between walking and running), there is a brief period of double support. This is not jogging, but rather a bouncing gait, with no flight phase, that may just prove to be quite an economical running solution for weekend warriors.

Despite the quality of presentations across the three days, it all came down to the final presentation from the man we were all here to see – Dr Benno Nigg. Benno summarized his research efforts to date, which of course is no small feat. What I appreciated most though were his recommendations of where the profession needed to go in terms of pursuing topic-related research:

·         Firstly, we must establish and compare between functional groups that have similar characteristics, injury incidence and injury locations/mechanisms.

·         Secondly, we need to understand comfort better… What is it, what does it mean and how do we measure it?

It is only then we can understand how footwear, orthotics and training can all be used as a comfort filter to reduce the rate of injury.

In summary, Calgary was a fantastic event, which at the same time was testament to the fantastic career of Dr Benno Nigg. A once in the lifetime experience of scientific dissemination and networking that I will perhaps never see again in my lifetime. It was an honour to be involved.