Performing two exercises back-to-back without resting—in what’s called a superset—is one of the best ways to squeeze a lot of muscle-building work into a short period of time. That’s how Sean De Wispelaere, an expert trainer for Men’s Health Thrive, could perform 7 rounds of this movement pair in just 2 minutes. Going from a powerful medicine-ball slam to a fast-paced mountain climber hits every muscle from head to toe—including your heart and lungs—but it zeros in on your abs.”First, you need to use your core muscles to stabilize yourself in the plank position as you quickly run your feet underneath you,” says De Wispelaere. “And then, right away, you need to pop up and use those same muscles to forcefully throw the ball into the floor.” Even though the challenge only lasts for two minutes, performing rep after rep of these intense exercises without resting will test your endurance, too. Here’s how it works: Perform 10 reps of the mountain climber. (Draw your left knee to your chest, and then your right knee. That’s one rep.) Then immediately perform 10 reps of the medicine-ball slam. That’s one round. Resting as little as possible, repeat as many rounds as you can in two minutes. Try it and let us know your score in the comments below. And for more fitness guidance from Sean De Wispelaere, check out his thoughts on Why the Exercises You Hate Are the Best Ones For You.