Sit on a bench, preferably one with a back support. Place your feet on the floor shoulder-width apart. Sit up straight with a dumbbell in each hand at arm’s length. Keep your elbows close to your sides and rotate the palms of your hands until they are facing inward.
Curl the dumbbell towards your shoulders making sure your palms are facing away from you. As you curl the dumbbells upward make sure your biceps are fully contracted. Hold the contraction for a second before lowering the dumbbells back to the starting position. Your forearms should be the only moving part of the exercise.
Perform 3 sets, 12 to 15 reps. Resting approximately 30 to 40 seconds between sets.