Bolt's 9.58 in Slow Motion

[James_Smith]

@sady

Imagine a muscle having two actions, relaxed and engaged, this muscle does not have to go through a cycling phase to work. If it is shorter between 2 points in a straight line, would it make sense to focus on moving the foot from the rear straight to the front without cycling, this is all he does.

Precisely my thoughts. Cycling the swing leg via bending at the knee more than is necessary to establish the optimal stride length relative to one’s power output is inefficient at that stage of the sprint.