Including one arm dumbbell preacher curls in your workout routine is a smart choice if you want to build well-developed biceps.
It is an effective movement that is used to gain not just mass but strength in the bicep muscles.
One of the biggest factors that makes one arm dumbbell preacher curls effective in increasing the bulk of the biceps is the exceptional isolation of the upper arm through stabilization when it is on top of the preacher curl bench.
Added stability is seen through the shoulder joint and front deltoids, and more particular on the forearm muscles along with the wrists and hands to keep a firm grip on the dumbbell.
Performing this exercise provides a high concentration to target and develop the upper arm muscles since the flexion and extension from the muscles is optimized.
How to do
Using a regular preacher curl bench, hold a dumbbell in one hand with a secure underhand grip (palms facing upwards).
Lock your elbow firmly in place against the pad of the bench and keep it in a fixed position throughout the entire movement.
Using a slow and controlled tempo, curl the dumbbell up while focusing all of your attention on a peak contraction in the biceps.
Slowly return the dumbbell back down to the starting position and repeat for the desired number of repetition and then switch to the other arm.
Make sure to lower the weight full way, If you can only lower it half way it is usually a sign that the weight is too heavy. Don't use too much weight When not using correct form, the preacher curl can be a very dangerous exercise. Using too much weight can have a severely negative effect on biceps tendon and shoulder joint strain. The preacher curl is designed for lighter weight, perfect form and a large range of motion.