Most would consider themselves lucky to reach the age of 100 - and even more so if they're mobile.
To be 111 and still work out every day sounds nearly impossible - but not for Henry Tseng.
In fact, the great-grandfather-of-two rides on a recumbent bike every day for 30 minutes at the Collins & Katz Family YMCA in Sawtelle, California, to keep in shape.
Born in Yokohama, Japan, but living in Los Angeles since 1975, Tseng has been exercising for most of his life.
In his 80s he could perform yoga headstands and in his 90s he participated in 6.30am aerobics classes.
Tseng believes his secrets to staying fit are quite textbook and says that anyone - as long as they keep a daily gym routine and stay positive - can follow them to achieve success.
Tseng, a retired entrepreneur, has been active all his life and joined the YMCA in 1978.
His daughter, Linda Hsia, told Daily Mail Online that, when her father was younger, he used to enjoy swimming and playing outdoor sports.
"My parents have always lived a healthy lifestyle," she said. "They did not do drinking, smoking drugs, none of those things."
Hsia said that in the 1950s, when they were living in Hong Kong, Tseng and his wife Annie - who passed away in 2013 at age 100 - had a yoga master come to their house and teach them how to yoga.
"Literally, into his 80s, he could do yoga headstands and he was doing shoulder stands into his 90s," she said.
Currently, he pedals on a recumbent bike for half an hour, does yoga poses in his wheelchair or works on strengthening his grip by squeezing stress balls.
"He does 30 minutes on the bike and he watches the clock, making sure he gets his whole 30 minutes and no less," Michelle Dodson, the assistant director of Healthy Lifestyles at the Collins & Katz Family YMCA, told Daily Mail Online.
"And he makes sure the caretakers who bring him get on the ellipticals and treadmills too. They're not allowed to just sit there and wait for him."
Up until Tseng was 102, he would partake in the 6.30am adult fitness class three times a week that Dodson taught.
"He was driving there himself into his 90s and we had to get him to stop," she said.
"I'd sometimes go dragging in there, barely making it in at 6.30 in the morning, and there would be Henry and all my energy would suddenly come back."
Hsia says that she's had members of the class tell her that her father was their inspiration for attending.
"They would say: 'I would wake up in the morning and didn't want to get out of bed but then I thought that your father was going to be there so I can too'," she said.
Dodson says the class is a low-impact fitness class interweaving cardio, weights, free weights, and then stretching at the end.
"I remember one time, we went down on the floor to stretch - and I think Henry was about 100 at the time - and he just went up in a full-blown shoulder stand," she said, laughing.
"He was clearly showing off but there are these 80-year-olds and 90-year-olds looking at him and thinking: 'Hey, I've got a lot of time left yet'."
Most would assume that intense exercise is difficult to perform as we age.
In general, VO2 max, a measure of how well our bodies can use oxygen and the most widely accepted scientific indicator of fitness, begins to decline after about age 50, even if we frequently exercise.
But Dr Veronique Billat, a professor of exercise science at the University of Evry-Val d'Essonne in France, told The New York Times last year that if older athletes exercised intensely, they could increase their VO2 max.
Tseng's next piece of advice is on diet - and it's quite simple. He eats little junk food and lives by the adage of eating "breakfast like a king, lunch like a prince, and dinner like a pauper".
A 2013 study conducted by Tel Aviv University found that those who made breakfast their largest meal had lower levels of insulin, glucose and fat in their blood than those who made dinner their main meal.
The researchers say these low levels can help lower the risk of both diabetes and heart disease.
Hsia said her father's breakfasts currently consist of two soft-boiled eggs, half a grapefruit, half a banana, bread with butter and jam, half a bowl of cereal or oatmeal, a cup of coffee and a glass of orange juice.
Lunches differ between Chinese, Italian and Mexican, and occasionally a trip to McDonald's.
His dinners are much simpler and rotate between baked chicken, ground beef, pulled pork, omelets or soup, the LA Times reported.
"He eats a ridiculously scrumptious breakfast, but I think it's because he didn't eat much dinner so in the morning he eats all of it," Hsia said.
He doesn't cut any foods out of his diet and, in fact, goes to Starbucks after every workout session to get a mocha latte.
Lifestyle may also play a factor. Tseng says he's "very positive" and he loves being around people and talking to them.
A 2005 study found that older people with a large circle of friends were 22 percent less likely to die than those with fewer friends. And a 2007 study revealed that chronic loneliness can actually cause disease at the cellular level.
However, there could be other factors at play in his ability to live past 100.
A study from September 2016 found that some people are destined to age quicker and die younger than others - regardless of their lifestyle - due to an 'internal genetic clock'.
But Tseng shows no signs of slowing down and says his best kept secret to his long life is to put on a smile every day.
"I have lots of small troubles like everybody, but I just say, 'forget about it,' Tseng told the LA Times last month. 'Nothing is impossible.'"
Dodson said this positivity has changed her mental approach to how she views life and living.
"He is my example that if you live that long, you can live with quality," she said.
"When I asks him what's his secret, his answer is: 'I smile.' I've never seen him upset. He's just pure joy."
HENRY TSENG'S DAILY ROUTINE
Two soft-boiled eggs, half a grapefruit, half a banana, bread with butter and jam, half a bowl of cereal or oatmeal, a cup of coffee and a glass of orange juice
Lunch: Italian, Chinese or Mexican food - sometimes a trip to McDonald's
Exercise: 30 minutes on a recumbent bike at the Collins & Katz Family YMCA
Snack: Starbucks mocha latte
Dinner: Rotation between baked chicken, ground beef, pulled pork, omelets and soup