Muscles worked
The wrist curl trains the muscles on the inside of your forearm, the ones that bend your wrist. The finger flexors sit in the same area and help out, since you hold the bar the whole time. If you let the bar roll a little way into your fingers at the bottom and close your hand again on the way up, your fingers and grip get even more to do. The back of the forearm, which straightens the wrist, gets hardly any work here.
Common mistakes
- Bouncing at the bottom. With a heavy bar it is tempting to let your wrists drop back and use the rebound for momentum. Pause for a moment in the low position and start each rep from a standstill.
- Letting the bar roll to your fingertips. Only roll it as far as you can safely close your hand again. If the bar feels as if it is about to slip, roll it out less or go lighter.
- Doing them at the start of the session. Tired forearms make it harder to hold the bar in deadlifts, rows and pull-ups. Save wrist curls for the end, once the heavy pulling is done.
Variations and alternatives
- The dumbbell wrist curl lets each hand work on its own and can be done at home with a pair of dumbbells.
- The reverse wrist curl trains the back of the forearm and pairs well with this one in the same session.
- The wrist roller works both sides of the forearm with a single piece of kit.
Sets and reps
To build muscle, 2 to 4 sets of 10 to 15 reps works well, and for endurance you can go up towards 20. Heavy sets of a few reps do little here and usually turn into bouncing. The guide to sets and reps explains how to choose.
Add reps first, and once you can do 15 in every set, add weight with the smallest plates the gym has, as a big jump soon ruins your form in such a small movement. That is progressive overload on a small scale. Two sessions a week is plenty for most people, and the guide on how often to train says more.