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.

Although the TRX Suspension Trainer uses nothing more than your body weight for resistance, it can provide some truly brutal workouts. If you need proof, just try the 40/40 Challenge.

Complete the 40/40 Challenge by doing as many TRX Atomic Push-Ups as possible, followed immediately by TRX Rows. The challenge ends if you rest by touching the floor or standing up.

TRX Atomic Push-Up

• Adjust the straps to 6-12 inches off the ground
• Assume the push-up position and put your feet in the straps
• Tuck your knees to your chest, straighten them back out and do a Push-Up
• Keep your body straight during the Push-Ups. If you start sagging, you’re done

TRX Row

• Adjust the straps to belly-button height
• Stand under the TRX anchor, hold the straps and lean back
• Pull your chest to your hands, then lower all the way back down
• Keep your body straight

The Challenge

Do as many TRX Atomic Push-Ups and Rows as possible without resting.

How Do You STACK Up?

Rookie: 25-29 reps of each exercise
Pro: 30-39 reps
All-Star: 40+ reps

How to Win a STACK T-Shirt

1. Complete the challenge by Aug. 10
2. Follow STACK on Twitter (@stackmedia)
3. Tweet your results as Atomic Push-Ups/Rows. So if you completed 35 Push-Ups and 40 Rows, you’d tweet 35/40. To qualify, your tweet must include #STACKChallenge

Congratulations to @twhitey13 for winning a STACK T-shirt by completing last week’s Plate Push Challenge.

Get Better

Looking for more TRX challenges? Start with these articles:

• Drew Brees’ Crazy TRX Single-Arm Pendulum Leg Swings
• 3 TRX Exercises for Athletes
• Antonio Brown’s One-of-a-Kind TRX and Pilates Workout