- Sit on a flat bench with your legs spread, knees bent and your feet flat on the floor with a dumbbell between your feet.
- Use either arm to pick the dumbbell up and hold it with an underhand grip.
- Place the back of that upper arm on the top of your inner thigh on the same side. Your palm should be facing away from your thigh.
- Keep your arm fully extended downwards without letting the dumbbell rest on the floor. This is the start position.
- Curl the dumbbell forward and up in a smooth arc, contracting your biceps and exhaling.
- Continue curling the dumbbell upward until your biceps are fully contracted and the dumbbell is at shoulder level. Hold for a count of one while squeezing your biceps.
- Return to the start position in a controlled, smooth arc inhaling as you do so. Do not swing the dumbbell down.
- Repeat for all the repetitions for that arm then switch and repeat the movement with your other arm.
Throughout this exercise, only your forearms should move. This exercise can be performed standing in a bent over position. Here there is no upper arm support so it's important to ensure there is no movement or swinging of the upper arm. This harder version of concentration curls isn't recommended for people who suffer lower back issues.