This weekend, 366 of America’s toughest, gutsiest, most formidable distance runners hit the streets of LA for the US Olympic Trials marathon. And while the men’s race was dominated by 29-year-old Galen Rupp, who cruised to a 2:11:12 victory in his marathon debut without appearing to so much as break a sweat, the real standout performance of the day came from women’s champ Amy Cragg.

Cragg, who scrapped her way to a heartbreaking fourth-place finish in the 2012 Olympic Trials for London, ran the race of her life on Saturday, clocking a solid 2:28:20 in the punishing heat to carry the day. She ran the bulk of Saturday’s race alongside training partner Shalane Flanagan, a three-time Olympian who was favoured for the win. But with about 5K to go, Flanagan began to struggle, and soon after, to falter.

Rather than seizing this late-in-the-race opportunity to open up her lead and drop Flanagan along with the rest of the field, Cragg hung back, coaxing Flanagan to keep going, assisting her through the last aid station, until a surging Desi Linden forced her to finally take off.

“I don’t think I can do this,” the distressed Flanagan cried out.

But she did – collapsing across the finish line into Amy Cragg’s arms, having clung desperately to her third-place position to secure a spot on the 2016 Olympic Team.

Amy Cragg pulled off a redemption marathon of epic proportions on Saturday. And though her time ultimately carried the day, she doubtless could have run an even stronger race had she not clung with such stubborn, unwavering loyalty to a struggling Shalane Flanagan over the final miles.

And Cragg is hardly the first elite marathoner to display this extraordinary level of concern for a competitor. In the 2009 New York City Marathon, Ethiopian Derartu Tulu stunned onlookers by slowing her pace to encourage her longtime rival Paula Radcliffe, who had fallen off the back of the elite pack.

“Come on,” Tulu called out as the pair traversed the Queensboro Bridge. “We can do this.”

Tulu, too, was all but dropped by the surging elites while she repeatedly attempted to coax a flagging Radcliffe back to life. She ultimately caught up to the leaders, overtaking her competition to win the day in 2:28:52. When Radcliffe, injured and in tears, struggled to a fourth-place finish minutes later, Tulu simply embraced her.

Both Derartu Tulu and Amy Cragg demonstrated uncommon compassion for their competitors, ostensibly risking their own races in the process. And these remarkable episodes don’t represent a one-off, for either runner. When asked about Tulu’s behaviour following the race, Radcliffe remarked, “That’s just Derartu. She’s always lovely like that.”

It is tempting to write off an overgenerous disposition like that of Cragg or Tulu as a liability in an elite athlete. But in reality, runners who invest in the well-being and performance of their fellow competitors often outperform those with more individualistic values over the long term.

Which might explain the dominance of athletes like Rachel Hannah, who took home the Canadian title in the 2014 Half-Marathon Championships after defending champ Krista Duchene fractured her femur in the finishing stretch of the race. But Hannah, at the time still a relative up-and-comer on the national scene, declined bask in her post-win glory. Instead, she rushed to the side of the injured Duchene, ignoring requests for post-race pictures and interviews until she could be sure her fiercest competitor got the care she needed.

And the athletic predisposition to an altruistic mindset isn’t limited to elites, either. Both seasoned recreational runners and newcomers to the sport alike can attest to the tremendous benefits of running with a club, team, or crew. Running might be an individual sport, but there’s an undeniable energy and momentum that can be drawn from a collective mindset.

So why do compassionate, team-oriented runners tend to perform so well? The benefits are twofold:

First, running is tough. And marathon running, even tougher. A common (and particularly effective) strategy for pushing through the gruelling miles is to mentally “switch off” – to turn your attention away from your own discomfort and onto literally anything else. So when an athlete’s mind is preoccupied with concern for the well-being of a competitor, it becomes much easier to ignore their own discomfort and push on.

The fact that Amy Cragg or Derartu Tulu were able to win their races, while also mustering the necessary energy to encourage and cajole their struggling competition, is undeniably remarkable. But the strength these women drew upon to pull off such victories existed, at least in part, because of their concern for the well-being of others. Altruistic acts have the effect of drawing us out of ourselves – whether we’re volunteering for a cause, donating to charity, or encouraging a competitor – in turn making us more resilient in the face of pain, hardship, and personal distress.

Second, no matter how hard you train, you are bound to have a bad race here or there. Setbacks and failures are an inevitable part of competition – the devastating lows that make the experience of victory that much sweeter. So when you spend your time encouraging the efforts of others, your own internal monologue – what psychologists call your “self-talk” – becomes correspondingly more positive and encouraging.

Long-term success in distance running depends, more than anything else, on consistency and dedication. Which makes your framework for handling failures and setbacks of critical importance. When we offer encouragement or consolation to a struggling fellow runner, we are also sharpening our own internal coping skills. We teach ourselves resilience by nurturing it in others.

Altruism, as it turns out, has a very practical silver lining.

Like Derartu Tulu or Rachel Hannah, Amy Cragg’s tremendous display of empathy, camaraderie, and sportsmanship in Saturday’s race demonstrates once again the wisdom of that hard-worn proverb: shared joy is twice joy, but shared sorrow is half sorrow.

Chase big dreams.