The number of masters athletes in the United States is on the rise. This is attributed to a growing population of more than 300 million people, an aging subpopulation of “baby boomers,” and a culture enamored with sports.
In 1987, the first National Senior Games had 2500 participants (all older than 50 years), which more than quadrupled to 10,100 participants in the 2011 games, despite more stringent qualifying standards. Similarly, the number of athletes older than 50 years in the New York City marathon increased 119% from 1983 to 1999, with significant improvement in completion times as compared with younger age groups.
The masters athlete is typically defined as older than 35 years (as this is the age at which cardiovascular issues tend to become a greater cause of morbidity) who either trains for or takes part in athletic competitions often specifically designed for older participants. Many of these athletes are experienced competitors who continue their athletic pursuits after their sports careers have ended, while others are individuals who return to sports after extended periods of inactivity or simply participate and train sporadically.
-Source: Sports Health, August 28, 2014