The farmer's walk may look simple, but it's a super-hard, core-crushing exercise if you carry enough weight. "Every muscle from your shoulders to your hips has to stabilize as the weight shifts with each step," says BJ Gaddour, C.S.C.S., creator of Men's Health StreamFIT. And holding a heavy load for a long time taxes your grip and forearms, which are often neglected during your regular routine.

The downside: After a while, walking back and forth with the weight by your side can get boring. But Gaddour came up with 31 unique variations that will not only carve your core, but also test your strength, endurance, and willpower.

Check out the video below for demonstrations of each move.

MH Standard Player for WordPress
600x338
Theme: Light

Gaddour recommends hauling 75 to 100 percent of your bodyweight for 30 seconds or 25 yards to start. After you nail one variation, try your hand at another, trickier version of the exercise. If that's too difficult, choose a lighter load, but walk for 60 seconds or 50 yards. Perform multiple carries for a full workout, or try one or two for a quick, hard-hitting finisher. (Add these 4 Post-Workout Moves That Burn Fat to your regimen, and that extra belly roll will be gone soon.)

And for more than 200 follow-along workouts from Gaddour, check out Men's Health StreamFIT today!