Age is nothing but a motivator for these competitors.
While the record books are aflutter with the likes of Michael Phelps becoming the oldest U.S. male swimmer to win gold in an individual event at the seasoned age of 31 (while the oldest member of the U.S. swim team in Rio at all this year is Anthony Ervin at 35), it's easy to forget that there's no actual age limit at the Olympic Games.
Of course some bodies — especially athletes' bodies — don't do what they once did as the years go by, and it takes almost a superhuman amount of drive to keep that inner competitive flame burning for a decade, if not just within the four-year gap between Olympics.
U.S. & World
So most of the 10,500 athletes who came to the 2016 Rio Olympics are on the young-by-any-standards side, the youngest being 13-year-old Nepalese swimmer Gaurika Singh, who was still years away from being born when the oldest competitor in Rio went to her first Olympics.
Though some of the events that boast the more seasoned competitors aren't as taxing on the body as others, every single one of the older Olympians deserves the utmost respect for their dedication and discipline as they prove that there is no reason to stop doing what you love so long as you want to keep doing it.
First off, meet Oksana Chusovitina, the other gymnast everyone's talking about. Though really there's no need for introductions, since she's been at every Summer Olympics since Barcelona in 1992--five years before Simone Biles was born.
The 41-year-old athlete started her Olympic career competing for the Soviet Union (the gold-winning Unified Team in 1992); then represented Uzbekistan in 1996, 2000 and 2004; and then Germany in 2008 and 2012.
Her best individual finish was a silver in the vault in 2008--and that is the event she will be competing in again on Sunday (for Uzbekistan once again) in Rio after ranking fifth in qualifying.
"I am feeling good," Chusovitina, the 5-foot-tall oldest Olympic gymnast in history, said in an interview last month. "On the podium, everyone is the same whether you are 40 or 16. You have to go out and do your routine and your jumps. But it's a pity there are no points for age."
Of coures, staying healthy has been key.
"I have no pain, no problems," added the now seven-time Olympian, who is also mom to a 16-year-old son. "The toughest for me is to wait until the next training."
Asked how her unprecedented endurance has been possible, Oksana said, "I don't know how I stay fit, I think you have to ask my mother."
Also making history in Rio is U.S. cyclist Kristin Armstrong, who briefly retired after the London Games but celebrated her 43rd birthday Thursday one gold medal richer after winning her third straight Olympic time trial.
The mom of 5-year-old son Lucas (and one of the many athletes who have a day job off the bike, as community health director for St. Luke's Health System) is the oldest female cycling medalist of all time and is the first American woman to win an individual event in three consecutive Summer Olympics.
"It was probably the hardest journey that I've been through," Armstrong told NBC Sports after her emotional finish. "That's why I think that we keep coming back, trying to get to the pinnacle of sports, which is the top step of the podium. Each and every day my team around me, my family, sacrificed so much for me to be here. I sacrificed so much, and the emotions--I still have to pinch myself, but there was the emotion of exhaustion, the emotion of 'I can't believe this,' and the emotion of so much excitement that it happened."
"And people have asked me, over and over, 'Why? Why am I back?' And it's because I can. And I showed it today and I'm so proud, and I'm so excited that I won my third gold medal. It's a historical moment in sports, for women in the Summer Games, in the U.S."
There is also horseback rider Mary Hanna of Australia, who, at 61, is the oldest competitor at the Rio Olympics--followed closely by British show jumper John Whitaker, who just celebrated his 61st birthday Aug. 5.
"Every time I have done the Olympics, I've thought, this is probably the last time I will do it; but, after the last time, I thought: I am going to keep going with this because I feel fit and healthy and why shouldn't I? So, here I am," the grandmother of three, who will compete in the team and individual dressage events, told Australia's ABC News.
This is Hanna's fifth trip to the Olympics, her first being the 1996 Summer Games in Atlanta (she was not in Beijing in 2008).
Asked what it meant to him to be chosen to his sixth Olympic team, John Whitaker cheerfully told London's Daily Express, "It means I'm old!" He added, "No, seriously, this means a lot. The Olympics are the pinnacle. I feel lucky that I can still have a go at my age. Most sportsmen get probably one or two chances to go to the Olympics."
The equestrian sports in Rio actually boast more than a few veteran Olympians still riding high. In fact, the United States' Phillip Dutton, 52, became a six-time Olympian in Rio--and is taking home a bronze medal for his efforts in individual eventing, which combines dressage, show jumping and cross-country riding. Which makes Dutton's horse, Mighty Nice, a mighty triathlete.
Joining him on the U.S. equestrian team in the over-40 club, now four-time Olympian Steffen Peters, 51, who qualified for individual and team dressage, and Beezie Madden, 52 (and also now a four-timer and past two-time gold medalist), who qualified in individual and team show jumping.
And just to name a handful of other riders of a certain age:
William Fox-Pitt, 47, of Great Britain; Ingrid Klimke, 48, of Germany; Edward Gal, 45, of the Netherlands; Mark Todd, 60, of New Zealand; Ludger Beerbaum, 52, of Germany; and Nick Skelton, 58, of Great Britain, a member of the Olympic gold-winning jumping team in 2012.
And while their events don't score the prime-time network slots, the riders are often revered among their fellow countrymen and women. For instance, show-jumping champion Jeroen Dubbeldam, 43, was chosen out of hundreds to carry the Dutch flag during the Rio Opening Ceremony.
"I am proud that I can walk on behalf of 242 athletes with our flag. At the Olympics, you stand for your country, for the whole Team NL," Dubbeldam,who won individual gold in Sydney in 2000, told Noelle Floyd last week.
Moroccan rider Abdelkebir Ouaddar, 54, is a veteran of international competition but he will be riding in his first Olympics--and he too was chosen as his country's flag bearer during the Parade of Nations.
The show jumping specialist was once afraid of horses but learned to ride as a boy after being adopted by the Moroccan royal family.
King Mohammed VI provides the horses he uses to train and ride in competition, and this is the first time Morocco has ever sent a competitor in this sport to the Olympics.
"King Mohammed VI puts everything at my disposal to make me feel at ease. First class tickets and everything you need. I'm really lucky, I can say that I am treated like a king too," he's quoted on the Longines Global Champions Tour site.
Also, it was 41-year-old Hoang Xuan Vinh who earned Vietnam's first-ever Olympic gold medal over the weekend, winning the 10-meter air pistol shooting event.
The United States' shooting team boasted five-time Olympian Emil Milev, 48, 51-year-old Francisco Boza took aim for Peru, 54-year-old Warren Potent qualified from Australia and 51-year-old Joo Costa represented Portugal. On the ladies' side, 45-year-old Satu Mkel-Nummela of Finland, the 2008 gold medalist in women's trap shooting, finished 10th in Rio.
And if the thought of a few sprints gets you winded, check out the marathon field.
Team USA's Meb Keflezighi, who won silver in Athens, is competing in his fourth Olympic Games at 40. But he's got fellow 40-year-old Bernard Lagat to look up to, Rio marking the fifth Olympics for the veteran distance runner, who won the 1,500-meter silver in Athens while competing for Kenya (he joined Team USA after the 2004 Summer Olympics).
Australia's Scott Westcott will be just several days shy of his 41st birthday when he runs the marathon in Rio--in what will be his Olympic debut, making him the oldest-ever first-time Olympian from Australia in track and field.
"I believe I have kept my hunger burning for close to 20 years. I am probably in the best head space of my career," Westcott told The Guardian in May. "Training is going well and not having just completed a marathon in early 2016 means I am fresh and ready to go."
Each making her fifth Olympic appearance is 40-year-old Chilean marathoner Erika Olivera, who was also Chile's flag bearer during the Opening Ceremony, and 42-year-old Jo Pavey, making her the first British athlete to compete in five Olympics.
"I'm absolutely thrilled," Pavey, who's running in the 10,000 meters on Friday, told The Telegraph when she was selected for Great Britain's Olympic team. "When you're a young girl dreaming of going to the Olympics, you never think you could be going to five. Standing on that start line and looking up at the flame is really emotional. Never in my wildest dreams a few years back did I think I would be competing at the Olympics at my age."