How fast can you run?

Yesterday we were at a wildlife preserve and saw a cheetah. She was inside a fenced off area that was comfortable and seemingly spacious but was probably much too small for her. Cheetahs, my five year old tells me, are the fastest land animal on Earth. They can go from 0 to 60 in 3 seconds and can reach top speeds of up to 70 miles per hour. 

But could this cheetah do that? Did she have enough room to do that before having to slow down before reaching the end of her enclosure? I wasn’t sure.

What about me and you? 

Are we in the right environments to reach our top speeds? Our maximum output? Our life’s best work? 

What would you change?