Sergey Marchuk

In 1977, Marchuk skated 3:56.65 on the 3,000 m on the Medeo rink of Alma-Ata, significantly below Ard Schenk's world record time of 4:08.3.

Unfortunately for Marchuk, the tournament had not been approved by the International Skating Union (ISU) and so his time was not recognised as a world record.

It would be 15 years before anyone, officially or unofficially, skated the 3,000 m faster than Marchuk had.

This happened in 1992 when Thomas Bos skated an official world record of 3:56.16 at the indoor arena of Calgary – the Olympic Oval.

In addition, Eric Heiden skated even faster (1:14.47) at that same meet.