The start often determines the end of a track sprint race. A great start out of the blocks can often mean the difference between victory and defeat in a race often won by 100ths of a second. We use video to analyze one of the great sprinters, Tyson Gay as he starts a fast race.

The IAAF World Championships begins in less than a month and all eyes will be on the 100m and 200m world record holder, Usain Bolt from Jamaica. We all remember the Beijing Olympics in 2008, when Bolt ran the 100m in 9.69 seconds, throwing out his arms and pumping his chest before crossing the line. There has been a lot of speculation about how fast he could have run with some suggesting a time of 9.55 seconds.