Have you ever shoveled snow or gravel, or dug a big hole? Where were you sore the next day? Your abs work hard to rotate your torso-and prevent it from rotating too much-and when you make them work with a lopsided load, such as a shovel with its scoop full, you’re activating just about every muscle fiber the core has to offer.

The macebell gravedigger simulates this exactly-but you’ve probably never had a chance to try it, because your gym doesn’t carry a macebell, a bar with a round ball fixed on one end. You can pick one up at macebell.com, or rig one up yourself with a barbell, a weight plate, and a sturdy collar or clamp.

How to Do It

■ Grasp the bar as you would a shovel. The closer together you place your hands, the harder the move will be. Push your hips back and bend forward until you’re in the position of a man about to shovel. Explosively extend your hips and raise your arms as if you were shoveling dirt over one shoulder.

■ You can perform the gravedigger as a strength exercise with, say, three sets of 8-10 reps, or use the macebell for conditioning, with a light weight and higher reps. Each set, switch the hand that’s on top and the side you shovel over.

■ An equally great gravedigger variant is to make a lateral shoveling motion. Set up the same way, but place your bottom hand on the butt end of the bar. Wind up to one side, then rotate to the other without pivoting either foot (like bailing water).