Every week, a new STACK Challenge gives you an opportunity to test your athletic ability and win a STACK T-shirt. Take the challenge and enter to win by tweeting your results with #STACKChallenge.

For a tough end-of-summer workout finisher, hop into the pool and try the SEAL Swim Challenge.

Former Navy SEAL Stew Smith helps his athletes improve their conditioning by challenging them to swim hard for 15 minutes after their workouts. “Swimming after weight training is a great way to add endurance, which will really help in the fourth quarter,” he says.

Complete the SEAL Swim Challenge by swimming as far as you can in 15 minutes, resting as needed. Remember the standard pool is 25 yards long.

The Challenge

Swim as far as you can in 15 minutes.

How Do You STACK Up?

Rookie: 400 yards
Pro: 600 yards
All-Star: 800 yards

How to Win a STACK T-Shirt

1. Complete the challenge by Aug. 10
2. Follow STACK on Twitter (@stackmedia)
3. Tweet your results with #STACKChallenge

Watch next week’s STACK Challenge to see if you won.

Get Better

Learn how you can use swimming to become a better athlete by checking out Smith’s advice in this article.