Most great athletes play more than one sport in high school.
When they get to college, however, these great athletes usually pick one sport. The football player will hang up his track spikes and add an extra 20 pounds of muscle, while the field hockey player will give up juggling the soccer ball to better hone her stick work. They find the sport they are best at, and focus their energies appropriately. Doing any more would just be too much. Unless of course, you happen to be Katie Schumacher.