Diana Nyad's Cuba-to-Florida swim serves as an inspiration

Anyone who needs a perfect example of what healthy aging looks like need look no further than Diana Nyad. The 64-year-old long-distance swimmer recently completed the grueling 103-mile swim from Havana, Cuba, to Key West, Fla., without a shark cage - something nobody had ever done before, the Los Angeles Times reported. Battling jellyfish stings and rough windy conditions, the resilient baby boomer serves as a paragon of perseverance and active aging. 

Nyad had tried four previous times to make the swim. The first, in 1978, was called off after Nyad lost a dangerous amount of weight during the swim. She tried three times between 2011 and 2012, all of which were aborted. However, this time was different. Wearing a mask to protect her from stings, she made the swim in just under 53 hours. Even to observers who are more than three decades her junior, Nyad's commitment is astonishing. 

"She trains nonstop, like a beast. She's amazing," Chad Durieux, a coach at the center where Nyad trains, told the newspaper. "I think the motivation, what's driving her, is finishing what she started 40 years ago."

While Nyad's accomplishment may be one of the most impressive in recent memory, she is not the only older adult who has remained competitive in sports usually reserved for the younger crowd. Earlier this year in May, Japan's Yuichiro Miura, 80, became the oldest person to make it to the top of the 29,035-foot Mount Everest, The Associated Press reported. Fauja Singh, 102, is an avid marathoner. Despite not picking up running until his late 80s, Singh remains a staple in races around the world and recently completed the Mumbia Marathon earlier this year, according to CNN.