One of the surest ways to make guitar playing easier is to supplement your practicing with grip strength training. There are several popular methods for improving your hand strength, and they’ll all help your guitar playing in subtle ways no matter what your style is.
Several years into my own guitar playing adventure, I spent a complete summer practicing scales with difficult left-hand stretches for a couple hours every day. I emerged a master of a bunch of scales that I couldn’t play anymore because I’d developed tendinitis in my wrist and hand. I took it easier on the scales after that, but I also started a long-term hand strength training project in order to fend off any future tendinitis problems. I soon discovered that the benefits of increased grip strength extend beyond perpetually healthy hands. Each finger gets stronger, not necessarily more dexterous, but more able to accomplish all the fretting and bending tasks you give it with ease.
The most popular grip-strengthening tool is the simple gripper. Don’t let its ease of use fool you; they’re only for wimps if you do two reps per day. Try doing a thousand.
My favorite way to use this device is to do one squeeze with the left hand, then one with the right, two with the left, two with the right, etc. until I can feel some fatigue. (I usually get up to 15.) Then I turn around and descend back to one squeeze each. It’s quick, painless, and I can definitely feel the effect in my forearms.
Professionals might opt for a heavy-duty gripper. They make these at various levels of resistance, high enough to challenge expert phone book rippers and grip athletes (griphletes?). My brother gave me one of these after many years of attempting to crush each other during handshakes. He suffered.
Dynaflex makes the most popular hand-held gyroscope exerciser. These things are a ton of fun. They get your forearm muscles coordinated in ways you never dreamed of. I’ve found that while I’m using mine once a day, I never feel any inkling of overuse injury, no matter how many hours of guitar practice I put in.
Pullups might be a little overkill, but they are awesome for grip development, and they give a nice balance in developing the whole arm and more, beyond just the grip. (Alternatively, you could just hang from a bar for as long as you can. You might hate me for suggesting it.) Anything you can do with dumbbells is also great for your hands. Just don’t hurt yourself.
You don’t need to become a huge master phone book ripper in order to gain some guitar advantages from hand strength exercises. Even the slightest supplement to your practice routine can give you serious long-term payoffs. You’ll be less prone to overuse injury, and your hands will feel more confident overall. You can spend more time focusing on the music instead of squeezing every ounce of strength out of your hand to nail that F barre chord.