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.

Test your endurance and anaerobic capacity with a brutal rowing challenge.

For this week’s challenge, you’ll row as fast as you can on a rowing machine for 500 meters. Be sure to maintain correct form throughout the challenge by following these two rules:

1. Keep your heels flat on the pad throughout the movement.
2. Extend with your legs first, then finish with your arms.

The Challenge

Complete a 500-meter row as fast as possible.

How Do You STACK Up?

Rookie:  1:33 or more
Pro: 1:20 – 1:32
All-Star: 1:19 or less

How to Win a STACK T-Shirt

1. Complete the challenge by June 29
2. Follow STACK on Twitter (@stackmedia)
3. Tweet your results and include #STACKChallenge

1. Congratulations to Kristen Avvento for winning a STACK T-shirt by reaching All-Star level in last week’s 300-Yard Shuttle Challenge.

Get Better

Not an All-Star yet? Use these workouts to get better.

• 4-Minute Tabata Circuit
• Todd Durkin’s Jump Rope Workout
• 6-Week Conditioning Plan