Inside a US Men's Gymnastics Team Training Session With the Olympians Making the Internet Swoon

— -- The contenders for the U.S. Olympics men’s gymnastics team are aiming for gold at the upcoming Summer Games in Rio, but these guys have already found fame as Instagram stars.

The star athletes have won the hearts of thousands of fans by posting photos of themselves, often shirtless at the gym.

Or in their leisure time.

Or at the beach. This photo of the crew in Rio, which team member Danell Leyva posted in January, has more than 4,000 likes.

“Nightline” was invited to the U.S. men’s gymnastics team’s training sessions in Colorado Springs, Colorado, to get a peek at what it takes to prepare for the upcoming Olympics.

The 16 athletes, an eclectic bunch, are contending for five spots on the team. The youngest is 19 years old, and the oldest is 29.

“We don’t go into this competition expecting anything but greatness, essentially,” Sam Mikulak said. “We’re training to be the best in the world.”

And Dennis McIntyre, vice president of the men’s gymnastics program, said deciding who makes the team is “really difficult.”

“It’s a puzzle piece, a little bit because we’re looking for five guys that fit best together on the events to maximize the team score,” he said.

These guys spend more than 30 hours a week in the gym, with thousands of flips, spins and jumps — and falls.

“When I first started to do crazy flips on p bar, it definitely hurt a lot,” Donnell Whittenburg said. “But once you get used to it, you know when to kick out and when to land safely.”

“And you build up a callus and strength too,” said Jake Dalton.

And when they say callus, they mean the whole hand is one giant callus. “Hands of a man,” C.J. Maestas said.

Four of these men competed in London in 2012, but only one, Danell Leyva, brought home a medal, the bronze in the individual all-around event. Despite winning a medal last time, he said he’s not nervous about placing again at Rio.

“I don’t think that [medal] gives me any pressure at all, honestly,” Leyva said. “It’s a completely clean slate ... Guys are constantly getting better, constantly improving, especially these guys.”

Most of these guys can’t — and don’t — make a living off the sport. Three of them are still in college, including Akash Modi, who is studying mechanical engineering at Stanford University.

“It’s really just time management,” Modi said. “I sat down with some people at Stanford to talk about which classes to take and when for each quarter and not overload myself.”

Unlike its women’s counterpart, the U.S. men’s gymnastics team has won the Olympic all-around gold medal only once, at the controversial 1984 games in Los Angeles, when 15 Soviet-bloc countries boycotted.

“Winning a medal is a dream, an honor, but ... we don’t work this hard and shoot this far to win anything other than gold,” Chris Brooks said.

“I think we’ve got an incredible chance,” Dalton said. “We have so much depth. When you look at these young guys, they’re not only pushing themselves to get on that team, but they’re pushing us as well.”

Some of the men on the team come from families with a long gymnastic tradition. Leyva’s parents were on the Cuban national team. Others catapulted into it by chance. John Orozco said his father realized his potential after watching his years of practicing taekwondo, but the kids in the Bronx neighborhood where he grew up weren’t as welcoming to his doing gymnastics.

“Kids are not very nice at all,” Orozco said. “In the Bronx, gymnastics isn’t a well-known sport to begin with. With all of these stereotypes and preconceived notions, everyone thinks it’s a girls sport and it’s feminine. And it’s not really what society says the norm is for men. So I struggled a little bit through middle school and high school.”

But these days, it’s mostly injuries that these men struggle with.

“Microfracture on my ankle,” Brooks said, rattling off his injuries. “I blew out my right forearm, had five surgeries on that to get it fixed. Tore some ligaments, had those repaired. I’ve had 10 surgeries total now.”

“Like I said, gymnastics is very hard,” Leyva said. “Even if you like it, you’re crazy.”

But ever the athletes, they said even injuries aren’t an excuse to slack off on training.

“When you’re injured, there are so many things you can work on when you’re doing gymnastics,” Orozco said. “There should be no reason why you shouldn’t come into the gym and do something.”

It’s a team that keeps on fighting, so it seems fitting that Orozco starred in Gym Class Heroes’ music video for “Fighter” before the 2012 London Games. The video, which has had more than 46 million views on YouTube, has become the anthem for Team USA.

“You look at all the components — talent-wise, hard work, organization — and you put all of those things together, and we have the best in all of those areas,” Brandon Wynn said. “The last part of it that we have more of than anyone else is heart ... We fight to the end, no matter what happens.”