If you want to get wider biceps you'll have to focus on another muscle in the arm called the brachialis. The brachialis is situated beneath the biceps and is slightly visible if you flex your arm.
This muscle is responsible for elbow flexion and thus is an essential muscle for mountain climbing. By exercising this muscle you are building up the outer side of your arm. This creates a fuller appearance overall.
One exercise to attack this muscle is the hammer curl, as I performed this morning at the Y. This lift allows you to target the brachialis instead of the biceps.
Other muscles I targeted this morning were the:
Delts.
Biceps.
And back.
There is no final destination when it comes to lifting. It's a lifestyle. And we're always trying to improve.
Have a wonderful weekend!