Thousands of children across the United States dream of becoming professional athletes, yet less than one in a thousand high school seniors will go on to play in a major pro league. Of those select few, many will find that after a childhood of full-time commitment to their sport, their professional careers will likely be brief and injury-ridden. Within each of the top professional leagues in the U.S., the competition is fierce to not only get into the league, but to stay there—the average career in the National Basketball Association lasts less than five years, and in the National Football League only three and a half.The Anatomy of Competition in Sports The Struggle for Success in Major US Professional Leagues examines the role competition plays in each of the major sports leagues in the United States Major League Baseball MLB, the National Football League NFL, the National Basketball Association NBA, the Womens National Basketball Association WNBA, the National Hockey League NHL, and Major League Soccer MLS.