Your strong, powerful forearms are your infantry. They’re your grunts. In the U.S. Army and Marines, “GRUNT” stood for General, Replacement, UNTrained. We’re going to turn that last part into “UNTamable!”

I want you to do four sets of each of the movements below, back to back, no rest, switching up the order each time you do them. You’ll finish with three consecutive timed holds (hanging from a pull-up bar) with your rest period being double the time of your hang (i.e., if you hang for 42 seconds, rest for 1 minute 24 seconds, then hang again, and so on).

The Exercises

Here are your movements: wrist curls, wrist extensions, handshake curls (bending your thumb toward your forearm and back) using a dumbbell, and squeeze (Captains of Crush have a terrific selection of hand grippers that can sit on your desk).

For all four moves, start with a weight that stops you in your tracks at 10–12 reps for the first set, 15–20 the second, 20–25 the third, and 25-plus for the final set. You may want to have a friend drive you home after one week of this.