Sub-two hour marathon depends on controversial new shoe technology

The race is on for the first sub-two hour marathon, which seems like a ridiculous goal, but one that is quite likely going to fall sometime this year. I hadn't realized we were already so close ("we" meaning humanity, nothing to do with me personally): the current world record belongs to Kenyan Dennis Kimetto who ran 2:02:57 at Berlin in 2014, although Kenenisa Bekele of Ethiopia and Eliud Kipchoge of Kenya were just seconds behind that pace last year, and one of those two is probably the favourite to break the two hour barrier later this year.

What I had also not appreciated is the extent to which shoes and shoe technology influences marathon speeds. All three medalists in the Rio Olympics last year, as well as the winners of the Berlin, Chicago and New York marathons later in the year, were wearing Nike Zoom Vaporfly shoes, which retail for about US$250. Coincidence? I think not.

Now Nike has developed the Zoom Vaporfly Elite, and these are the shoes that are expected to expedite the sub-two hour record later this year. Apparently, the shoes can be individually tuned to the user in some way. They weigh 184.3g and feature a thick but lightweight midsole that returns 13% more energy than traditional midsoles, as well as cushioning the impact and reducing leg pain from long runs. There is also a stiff, curved, carbon-fibre plate embedded in the midsole, which acts almost like a slingshot or spring with each step, which saves a further 4% of the energy needed for each stride at any given speed.

Which is where the shoes become contentious. The International Association of Athletics Federation (IAAF), which is the body that sets and monitors the rules in athletics, has to decide whether they constitute any "unfair additional assistance" or "unfair advantage", which is the vague language employed in its rules on athletics shoes and equipment. Nike is confident that its new shoe does not break any rules, and there does not appear to be any formal IAAF approval or inspection process. However, others, like Todd Tucker (a South African exercise physiologist) and Yannis Pitsiladis (a British sports scientist), are not so sure, believing that the carbon-fibre plate effectively acts as a spring, which might make it inadmissible.

So, the IAAF, fresh from controversies over corruption, doping and the permissible levels of testosterone in women, have yet another tricky and high-profile decision to make this year. Maybe there ism a case for going back to the Ancient Greek model - no shoes, no clothes, nothing but the best efforts of the unadorned human body. And think of the potential television viewership income!