Performance and shoes
What follows is a classic story: Christian Mercier, marathon runner, 38 years old, 2h23, 150 to 200 km a week, has never had any serious injury, sponsored by Mizuno.
Goal: break 2h20.
Shoe habit: training (80% of volume) with the Precision model (55% TRC rating, 350 g -http://www.mizunousa.com/running/catalog/mensfootwear-), intervals and marathon events with the Ronin model (67% TRC rating, 200 g), 10 km events with the Ekiden model (73% TRC rating, 130 g).
Available but not used: the Universe model (78% TRC rating, 110 g) and the Prophecy model (74% TRC rating, 350 g).
I won’t go into details as to why most high-level athletes use several shoe models, or why ten years ago the majority of runners used even bigger and heavier shoes. I do believe though that a large number of athletes follow trends blindly, due to the influence exerted by the market and based upon the experience of older runners, who are used to running with bulkier shoes and who have found peace of mind using light trainers rather than more minimalist shoes.
After discussing with these athletes, the following motives have been raised for explaining their choice:
- I don’t see how I will perform better if I use more minimalist shoes for training and running marathons.
- I’m afraid that if I use more minimalist shoes during trainings or on the day of an event I will get “sored/tired/injured.”
I agree that high-level athletes already have efficient, well-developed biomechanics. The use of more minimalist shoes will have for them a much lower impact on stride efficiency, contrary to recreational runners. On the other hand, what does impact performance is the weight of the shoes. Study results are consistent throughout on this topic (2012-Perl, 2012-Franz, 2011-Hanson, 2011-Jenkins(R), 2008-Divert, 2009-Bonacci, 1985-Burkett, 2009-Squadrone, 1994-Flaherty, 1979-Catlin, 1981-Rlston, 1969-Soule, 1985-Martin, 1986-Jones). Each 100 grams at shoe level causes oxygen consumption to go up by 0.7 to 1% (each 1.0 % increase in VO2 would translate to a 2.94 m/min decrease in running speed.). Over the course of a marathon, for our case above, it means 1:30 minutes faster with the Ekiden model (2 x 70 g = 140 g = 1%) and 3 minutes with the Wave Universe model (180 g = 2%), but over 4 minutes slower with the Prophecy model. Please note that we are referring to weight only and not to biomechanical influences, which might, for some, increase speed even more.
Many people will tell you that the problem is the added mechanical stress of using a more minimalist model, which would probably cause runners to finish their races … on the knees and at a much slower pace at that. Solution: Transition slowly during training so you can use them during performance events. Such a process must follow tissue adaptation processes, must not interfere with the training load targeted and may cover a period as long as one to two years!
- Can these experimental data be applied concretely?
- Are athletes actually seconds slower due to this phenomenon?
- Are behaviors still influenced by the shoe industry?
- Will more runners opt for more minimalist shoes in the future?
In my own opinion: “yes” to all four questions!