IAAF says it has not had complaints about Laura Muir’s prototype shoes

Laura Muir after setting her new British indoor mile record. Picture: Michael Steele/Getty Images

The 25-year-old Scot covered the distance in four minutes 18.75 seconds at the Muller Indoor Grand Prix in Birmingham, smashing Kirsty Wade’s 31-year-old mark by five seconds.

The European indoor and outdoor champion over 1,500 metres, the so-called metric mile, was wearing what appeared to be prototype spikes based on Nike’s Vaporfly series, the cutting-edge shoe Eliud Kipchoge used to set a remarkable world record for the marathon in Berlin last year.

Nike says its marathon shoe offers a four per cent improvement in “running economy”, a claim which has prompted the IAAF’s technical committee to start discussing whether the sport should tighten up its regulations on footwear. When compared to sports such as cycling or swimming, athletics has traditionally taken a more relaxed approach to setting rules for its key piece of kit but that could be about to change.

According to a report on Wednesday, a rival manufacturer intends to consult lawyers about asking the IAAF to clarify the rules on what is permitted. The issue with Muir’s shoes, the report claimed, is that if they are prototypes, they do not comply with IAAF rule 143.2, which states “any type of shoe used must be reasonably available to all in the spirit of the universality of athletics”.

Nike’s Vaporfly road running shoes are available online and in shops but Muir’s new spikes are not.

Neither British Athletics, Muir nor Nike has responded to requests for comment but a spokesperson for the IAAF said: “Shoe technology is improving all the time.

“The IAAF has no evidence that this particular shoe does not conform to rule 143.2. If we do receive a complaint, our process is to refer the shoe for study and if it is proved to be non-compliant, it may be prohibited in competition.”

Muir has been in blistering form ahead of next month’s European Indoor Championships in

Glasgow.