Hips swaying, arms pumping, race walkers can look a little ridiculous compared to other Olympic athletes. Their awkward gait lacks the grace of the gymnasts, the fluidity of the swimmers, and the power of the sprinters, but their sport requires serious athleticism. The men’s 20 kilometer (12.4 miles) race walk will take place this afternoon (Aug. 12) in Rio, while the women’s 20km and men’s 50km races are next Friday (Aug. 19).
Perhaps the most important rule of race walking is that competitors must be in contact with the ground at all times. Judges along the course keep an eye out for walkers working in any “flight time,” time when neither foot is touching the ground. Fortunately for race walkers, the human eye isn’t fast enough to see when walkers are in the air, so world-class race walkers can get in about 40 milliseconds of flight time for each step without getting disqualified.
The characteristic hip sway of race walkers is key to their speed. Brian Hanley, a biomechanics researcher at Leeds Beckett University, told Vox that instead of rotating their hips the usual four degrees or so, like when the rest of us walk, race walkers rotate their hips around 20 degrees. This additional rotation gives them longer strides.
With the right technique, race walkers can set a pace that’s faster than the average runner. Some race walkers compete in marathons and pass runners on the course.
Like any serious sport, race walking has its share of doping scandals. Russian walker Sergey Kurdyapkin was stripped of his 2012 Olympic gold medal for the men’s 50km walk, and Italian Alex Schwarzer was banned from the Rio games after testing positive for banned substances earlier this year. Chinese walker Liu Hong was also penalized this year for doping, but she will compete in the women’s 20km walk next week.