KINGSTON, Jamaica — Researchers at the Southern Methodist University (SMU) have reportedly found an irregularity in Usain Bolt’s stride, which they said could account for his success as the fastest man in the world.

The speculation, according to a New York Times report, comes after Bolt appeared on a video screen in a white singlet and black tights, sprinting in slow motion through the final half of a 100-meter race.  

The researchers said they discovered the irregularity after examining the video, which shows that his right leg appears to strike the track with about 13 per cent more peak force than his left leg. Also, with each stride, his left leg remains on the ground about 14 per cent longer than his right leg.

They said, usually an uneven stride tends to slow a runner down. However, director of the SMU lab, Peter Weyand, said rather than being detrimental for Bolt, an uneven stride may actually be beneficial, the New York Times reported.

He suggested that it could be that Bolt has naturally settled into his stride to accommodate the effects of scoliosis — a condition that curved Bolt’s spine to the right and made his right leg half an inch shorter than his left, according to his autobiography.

The working idea is that Bolt probably optimised his speed based on the reflection of his asymmetry.

“In other words, correcting his asymmetry would not speed him up and might even slow him down. If he were to run symmetrically, it could be an unnatural gait for him,” Weyand was quoted as saying.

The lead researcher on the SMU study of Bolt, Andrew Udofa, said the study is not yet complete.

The initial findings were presented last month at an international conference on biomechanics in Cologne, Germany.