21’s is an intense arm burning exercise! This involves 3 variations of the bicep curl to give you an extremely good burn. This works best using a straight bar and a wide grip but may be done close grip as well. Remember a wide grip focuses more on the inside of the bicep while a close grip concentrates on the outside. The choice is yours! Subscribe to keep informed and notified of all my new workouts. Also please “LIKE” on my videos if you do 🙂