The sport's rules require that a race walker's knees stay straight through most of the leg swing and one foot remain in contact with the ground at all times.
这项运动的规则要求竞走运动员的膝盖在大部分的腿部摆动过程中保持笔直，一只脚始终与地面保持接触。
2
To make sure that they do not run, race walkers must have one foot on the ground at all times.
为了确保他们不跑步，竞走运动员必须保持有一只脚在地面上。
3
"That was a tough race and I've got a lot of blisters on my braking foot as the pedal was very hard to push," he said.