By Eric Astrauskas, Spec. Hons. B.A. (Kinesiology), P.T.S.
Weak forearms can limit your strength training in the gym. Most of the big lifts require strong forearms. If they are weak links they will hinder your progress. Forearm and grip strength is very important in many sports (martial arts, football, and powerlifting are good examples). Here are some quick tips to build massive forearms and bone-crushing grip strength.
1. Train your forearms at the end of your workouts at least 3x's per week.
2. Do finger pulls and handshake exercises with kettlebells. Also, add kettlebell training to your general workouts. Martial artists and strongmen have been using these tools for centuries and they have some of the best forearm strength and grip.
3. Avoid using lifting aids (lifting hooks or straps) as much as possible (even when doing deadlifts, pullups, or shrugs).
4. Do your hanging leg raises free-style without ab straps.
5. Perform towel pull-ups if you can. Or just hang from the towel.
6. Standard weight exercises that are great include; behind the back wrist curls, and reverse curls.
7. Use Fat Gripz (they make your lifting bars thicker and are much cheaper than buying fat bars).
8. Use Heavy Grips. These grippers are the best. They go from 100lbs. all the way up to 500lbs!
9. A forearm developer is also a great forearm tool. It is essentially a broomstick with a rope attached to it. You attach your weights and roll it up.
10. Last, but not least, the simple and highly under-rated/unused exercise of towel wringing. Soak a towel and wring out the water.
Forearm Training Video
Here are some good reference materials for improving grip strength and building bigger forearms:
Mastery of Hand Strength
Hand and Forearm Exercises: Grip Strength Workout and Training Routine