Forearm Exercise -- The Rock Climber's Forearm Workout
All athletes--not just rock climbers--who play a sport that demands forearm strength and use of the upper body can benefit from doing forearm workouts. Muscles need to break down in order to improve in order to get stronger. Anytime you exercise for strength you need to make forearms sore. Don't climb or workout with sore forearms. Wait until your muscle soreness has gone away before working on strength again.
Forearm Workout. Three key routines define the rock climber’s forearm workout. As a climber, you need strength and endurance in your grip as well as strengthening individual fingers, especially the thumb. Several forearm exercises below combine to make a very productive forearm workout. This is the key to getting your climbing ability to the next level. Think about it, the first thing to go is your grip. Your grip strength comes from the muscles in the forearm working together as a unit. Workout the forearm muscles in a specific deliberate program and you will see a big improvement in performance. The workout targets forearm strength, endurance, and individual finger strengthening exercises.
Forearm Strength. Static hangs on a bar is the best way to improve the strength of your forearms. Hang until your muscles absolutely fail - Note: I didn't say "hang until you can't stand it". When your muscles fail, you literally peel off the bar through lack of ability to hold a second longer without giving up. You must give it your most intense effort to hang on. Once you "peel" off the bar, shake out for 5 minutes. Then get back on and do it 3 more times. Do at least four sets. This will quickly improve your forearm strength. Since you are working until failure, it will also improve your endurance. You can use the same principle on overhanging bouldering caves (not to high though since you must go to failure). See Chin Ups.
Another good way to improve forearm strength is using a dumbbell. All repetitions should be high enough that you can just do 8 - 10. If you can easily do 10 reps you need to add weight. If you can not do 8 reps you need to decrease the weight. This training will workout the forearms to improve strength. Repeat the workouts for 8 - 10 repetitions. Do 3 sets.
Forearm curls. Do this strength exercise from a seated position. Sit on a bench or chair. Pick up the dumbbell holding it with a fist. Let the bar roll down to your finger tips then roll it back up into your palms again. For strength/endurance, do this for time not repetitions. Start out with 1 minute and work yourself up to 5 minutes or more. Climbing sport routes and indoor climbing routes take 5 to 10 minutes.
Forearm Endurance. Continuous low stress repetitive gripping improves endurance. Another version of above forearm strength exercise targets endurance a little more than you get with the static hang: While hanging, drop one arm and shake out your forearm for 5 seconds, then trade arms. Reach back up, grab with both, then drop the other arm and shake it out. This will add a lot of endurance while improving forearm strength. This is probably the best forearm exercise for rock climbers. This exercise best simulates the actual forces and stress on forearms during climbing.
You can also work strength/endurance on forearms by traversing on near vertical wall. Make sure it is vertical vs overhang to decrease the stress. Stay on the wall 20 minutes straight without a break. Start the 20 minute workout session with a pull up to get blood into your forearms and bump your heart rate up. You can drop one arm at a time to shake, but the key is still continuous low-stress gripping for 20 minutes straight.
Finger Strengthening Exercise. Fingers and forearms are related and perform similar functions in climbing. The difference between working forearms and fingers is with forearm exercises the fingers move together. Strengthening exercises for individual fingers will work the muscles controlling opposing movements. There is value in both types of exercises. Thumb strength is important in rock climbing. Thumbs grip sideways to rock or holds and provide the friction needed to stay on the hold. A forearm exerciser will help strengthen fingers, including the thumb.