To maximize forearm development, you need to train them in all their available movement patterns. This means going beyond a few sets of wrists curls and extensions at the end of your workout. With a sledgehammer, you can train pronation, supination, ulnar deviation, radial deviation and a host of circumduction patterns.

Think about people with the best forearms: mechanics, rock climbers, and strongman competitors. What do they have in common? They use their forearms in a number of complex patterns with high frequency and a long time under tension.

1. Pronation and Supination

2. Radial and Ulnar Deviation

Aim for 3 to 4 sets of 10-20 reps, pausing slightly at the top on each rep. And make sure you perform the exercise from both directions.

Always strive to get stronger or do more reps over time. You can make the exercise more difficult by simply moving your hand further away from the sledgehammer head. Mark out inches on the handle so you can accurately track your progress.

And if you're up for a challenge, try some front face levers:

The forearms can handle a lot of volume, and respond well to variety. So you could structure your week as follows:

  • Day 1 – Wrist flexion and extension (using dumbbells and barbells)
  • Day 2 – Radial and ulnar deviation
  • Day 3 – Supination and pronation

Once you've got a big pump after your final set of the day, stretch your forearms for 60 seconds per arm.

Related:  More Forearm Training Tips

Related:  Build a Strongman Grip and Big Forearms