Fall is here, which means it's also marathon season.
If you're running any races in the next couple of months, you could win some free shoes thanks to the company behind Strava, a tracking app used by runners and cyclists.
But getting the free swag is not going to be easy.
Strava announced it has partnered with New Balance to award those who can pull off a difficult feat -- not just running a marathon in itself, but accomplishing what's called a "negative split."
It means you have to run the last half of the marathon faster than the beginning half.
Runners who embark on the #StravaBackHalf challenge have to run a USA Track and Field certified race between October 9 and December 4.
If you succeed, you have to upload the race to Strava and submit a form on the company's website by December 12.
Strava says after submitting, runners who have completed the challenge will be rewarded with a code for free running shoes.
According to the company, runners will get to pick any pair of running shoes from newbalance.com.