Select the appropriate dumbbell weight matching your type of training. Sit back on an incline bench (about 45 degrees), lean against the backrest and push your feet to the floor in a shoulder-width position. Grab both dumbbells with the palms facing your torso (inwards) all through the motion.
Initiate the movement by flexing at the elbow (concentric bicep contraction) towards your shoulders without rotating your wrists. Keep your elbows locked in one position perpendicular to the floor. Go back to the starting position in the same way. Breathe regularly throughout the entire motion; breathe in as you start and breathe out with each elbow flexion on the way up.
Select the appropriate weight matching your condition, type of training and your fitness level. Start with lighter weight to master the technique well. Maintain your shoulders, knees and feet in one virtual line. Focus on abdominal breathing. Make sure your torso is straight and firm all the way through to avoid straining your lower back. Try to lock your elbows in one position.
Choose the number of repetitions to match your training type. Watch yourself in the mirror to eliminate using your trapezius muscles. Repeat the exercise with a frequency matching your breathing cycle and make sure to maintain the correct technique.
Incline hammer curls are a variation of hammer curls. What’s the incline position good for? First, you are sitting and thus your ability to cheat is greatly limited. Second, the biceps and brachialis muscles are stretched.
Some (especially the proponents of X-rep training) believe that stretch position triggers increased anabolism (this is very questionable and based on a clinical study involving birds but why not try it).
Hammer curls are curls in which the palms are facing each other. This is the most natural position of our hands thus causing least wrist problems.
Another advantage of hammer curls is that they build brachioradialis muscle that gives the appearance of volume to the forearm.
Hammer curls are usually done with two dumbbells, there is also a special barbell designed for hammer curls (unfortunately not available in every gym).
Notice: do not completely extend your arms. Always keep some pressure on the muscle. This is not only beneficial for the workout but will also prevent elbow injury.