WHAT ABOUT THE SHOE?

Sawe and Kejelcha wore the lightest “supershoe” in history: Adidas’ Adios Pro Evo 3. Adidas says it is “the fastest and lightest supershoe ever made”. It weighs less than 100g. Supershoes can improve running economy by about 4 per cent compared with conventional racing shoes.

The Adios Pro Evo 3 combines several features common in supershoes: very low weight, thick resilient foam and a stiff carbon-based structure in the midsole. The heel thickness is reported to be 39mm, just under the 40mm limit permitted by World Athletics.

While most runners benefit from supershoes, the effect is variable and not the same for all runners. Researchers have suggested this is due to two ways in which the footwear interacts with the runner.

Firstly, the foam and stiffening element can affect the “spring-like” bounce of the body as the foot hits and leaves the ground.

Secondly, they can change how the runner moves, including how the foot and ankle work, how long the foot stays on the ground, and the timing of energy return. As such, a shoe may be capable of storing and returning more energy, but the athlete still has to interact with it effectively. The exact benefit of the Adios Pro Evo 3 over other supershoes has not been independently measured, but even small improvements are likely to be important over a marathon.