Both Alistair and Jonathan Brownlee will tell you they are better athletes because of how they push and support each other.

British brothers Alistair and Jonathan Brownlee made history today at the Rio Olympic Games on many levels: Alistair, the eldest at 28, is the first triathlete to win back-to-back gold medals, and with Jonny’s bronze in 2012 and silver today, the pair are the first set of siblings to become two-time Olympic medalists in triathlon (only two other men have medaled twice—Canada’s Simon Whitfield and New Zealand’s Bevan Docherty).

The brothers, who stood on the podium together in London in 2012, controlled the race for the majority of the day. Exiting the swim in the lead group, then forming a bike pack of 10 athletes which maintained throughout the entire difficult course, they both started the run at the front of the field. On the last lap, Alistair pulled ahead of his brother to take the top spot, and the two fell to the ground at the finish line for what Jonny calls his most emotional finish ever.

Although it’s rare to see two such dominant brothers in one sport, they’re not the only siblings to race in Rio—in fact, six sets of siblings are on Team Great Britain this year alone.

Yes, the genes and home environment contribute to the Brownlees’ athletic ability, but as both of them will tell you, they are better athletes because of how they push and support each other.

“If I didn’t have Alistair around, I don’t know that I would be here,” Jonny said after the race. “I had to learn how to train from him. There was a time when I was 13 or 14 years old, and I wasn’t sure if I wanted to do the sport any longer, and Alistair made it very easy to come back to, because he was such a good training partner. He was the guy who used to cycle to school and he would get me out of the bed in the morning to cycle to school with him. He was the guy who when coaches said, ‘you’re doing too much training,’ he said ‘oh no, I’m doing the right amount of training.’”

They are the best-suited training partners for one another, known by their competitors as athletes who both train and race aggressively. “I believe they’re the best ITU athletes in history,” says Australian Aaron Royle, who finished ninth in Rio. “People who have raced in the past, people that are racing now, you won’t see many like them in the near future. They’re unstoppable on the swim, mash the bike and they’ve got the run prowess as well. They’re the complete athletes.”

Back in August of 2015, Alistair dealt with a major setback when he had to undergo ankle surgery. He didn’t start running until the beginning of December, and he had his work cut out for him as he got back in shape (“He got fat,” Jonny jokes). Once he was healthy, Jonny was a key part of getting him back into Olympic shape over the last six months.

“Jonny pushed me on sessions that would be harder than races—a few times a week just absolutely killing myself, going to bed at night unable to sleep because my legs hurt so much. Then waking up not being able to walk because my ankles were so stiff I can hardly move,” Alistair says.

They push each other daily, but not in an unsafe way that will destroy either of their chances for success. The key to a good training partner, Jonny says, is one thing: trust.

“Day to day, it’s all about trust,” he says. “When you have someone who you trust, who you know also has your best interest at heart, and you want to make each other the best that you can, it’s very positive. So many people go into training sessions just trying to get one over each other.”

Jonny, 26, has not beaten his older brother at the Olympic distance in the 17 times they’ve raced, but there never seems to be an ounce of resentment or jealously—only respect for his triathlon mentor.

“If I want to get beaten by any athlete, I want it to be Alistair,” Jonny says. “I realize how good he is.” When asked if he ever gets jealous, he says, “Well, I’m 26 now and hopefully I have a few years in me. If it’s at the end of my career and I’m still chasing that gold medal, maybe that’s when I’ll be jealous.”

Will we see the Brownlees return to Tokyo in four years? As you would expect, it’s too soon for that commitment.

“Four years is a long time to Tokyo, and I think we shouldn’t be thinking too much about it happening again,” Alistair says. “I think we should enjoy pulling off what we did today and be really appreciative that the last three months of training went so well, and that we managed to get the race to go our way today.”

RELATED PHOTOS: 2016 Rio De Janeiro Olympic Games – Men’s Race