Would you give up a chance at winning a race to help a fellow competitor instead?
London Marathon runner Matthew Rees did just that.
Rees stopped meters short of the finish line to help runner David Wyeth finish his race after he saw him struggling to stand.
"I took the final corner thinking 'right, it's nearly done, time to sprint', and I saw this guy and his legs just crumbled below him," says Rees.
"I saw him try to stand up again and his legs just went down again, and I thought 'this is more important, getting him across the line is more important than shaving a few seconds off my time".
The gruelling 26-mile course has a history of taking its toll on runners.
Now the video of the moment it happened is going viral with the internet dubbing Rees as the ultimate sportsman.
Social Media Presenter Aziz takes a look at the biggest online trends of the day.
Watch the video for the full interview.
