The answer comes courtesy of q.equinox.com-
"Balance...you better believe Mr. Bolt knows how to stabilize his body on one leg and use every single muscle in his hip and leg to stay steady. How? He has trained it, over and over and over again.
"...And it’s not just Bolt. Balance may be the most underrated quality in most of the greatest athletes of our time. It’s certainly not flashy, but it’s one of our body’s most fundamental abilities, and most professionals will rank balance (along with mobility) as the first and most vital skill necessary for optimal performance. In fact, the highly publicized strength, endurance, power and speed are actually nothing without a foundation of balance."
Read the full article- including a drill that will help you improve your balance- here: