I read a Frederic Delavier’s book « Strength Training Anatomy » and there is good stuff.
Standing with your legs apart and your arms outstretched. Hold the barbell in a pronated grip ( thumbs inside) :
Inhale and flex your arms
Exhale at the end of the movement
Back to the starting position by controlling the barbell’s descent
This exercice works the extensor muscles of the wrists : Extensor carpi radialis longus, extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi, extensor carpi ulnaris. And it works also the biceps, brachioradialis and brachialis.
Note : This an excellent exercice to strengthen the wrist joint, often weakened by an imbalance caused by the predominance of the flexor’s wrists muscles over the extensor’s wrist muscles. For this reason a lot of boxer and bench press champion do this exercice to prevent the wrists from vibrating with extreme weights.
P.S. : Do you want a free training program ? Click here