In the context of a previous post on foot strike pattern in a marathon…
94% were heel strikers and there was a statistically significant difference between the foot strike classification and race rank, with the forefoot strikers ranking ahead of the split strikers (asymmetry between left and right) who ranked ahead of the midfoot strikers who ranked ahead of the heel strikers. The 94% is similar to that reported by Larsen et al of 89% heel striking at the 10km mark and 93% at the 32km mark of a marathon. Larsen et al also reported no correlation between foot strike pattern and performance which the above study did find. The authors explanation for this difference was that in the Larsen et al study, the winning time was 2:55:16, compared to the above 2:22:17, so there were more runners running faster. Larsen et al had 266 heel strikers; 10 asymmetrical; 10 midfoot and no forefoot strikers; whereas the above study had 1865 heel strikers; 14 asymmetrical; 101 midfoot and 11 forefoot strikers so is powered more to find a significant difference.
…there was an intriguing presentation at the International Running Symposium by Martin Shorten last month. This meeting was to celebrate the retirement of Beno Nigg and featured a who’s who when it came to running research. I did a live blog from the event here and Blaise Dubois commented on the mtg here.
Martin covered several topics, but here are some snippets that I found interesting:
- In an online survey via Runners World that got 2,169,282 responses, the self reported foot strike was 15.7% forefoot strikers; 40.9% heel strikers; 43.4% midfoot strikers
- BUT; observed in slow motion videos of 11000 runners at the 2013 Boston Marathon: 95.6% heel strikers; 2.4% midfoot strikers; 2.1% forefoot strikers
- BUT, in the lab: of 17 runners that said they were heel strikers, only 14 really were; of the 20 that said they were midfoot strikers, not one them actually really were; of the 7 that said they were forefoot strikers, only 2 of them really were; ie 93% of those who said they were non-heel strikers were actually heel strikers
Conclusion: runners are pretty poor at self identifying their own foot strike pattern. We know from a previous study that only about 50% of runners got it right when identifying their own arch type.
Also of interest was that Martin has proposed a new gait that has not previously been described or documented in the literature based on his observation of Boston marathon. He called this “Grounded Running”. It’s a gait that is at a speed almost immediately above the walk/run transition and there is NO flight phase (which is part of the definition of typical “running”); it is more of a bouncy gait; it is a gait used by slower runners; it is possibly a more economical gait solution at the walk-run transition speed.
As always, I go where the evidence takes me until convinced otherwise…..and, of course, this is all based on the premise that foot strike pattern is actually even important.