Go get your gunz on:
Base strength
It's likely that a few extra inches on your pipes would be most welcome, but before you can pack pounds of muscle onto your biceps, you'll need to build up a decent strength base. "To achieve superior results, muscles and joints should move through a full range of motion," says personal trainer Chris Bathke. "Both bicep heads attach to the scapula and assist in shoulder movements, so relying only on single joint isolation movements that don't involve the back or shoulder shortchanges muscular development." Bathke recommends this simple self-test to determine whether your base strength is up to scratch.
The close grip chin-up
Hang from a bar, palms facing toward you with arms fully extended, and pull yourself up until your upper chest is even with your hands. If you can successfully perform 10 reps with strict form then you have decent arm strength. If not, then forget bicep curls for now and work on chin-ups.
Build it up
"Chin-up negatives are a good movement to improve strength, even for those that can't do a chin-up," says Bathke. Chin-up negatives are easier as they consist only of the second part of the chin-up movement: start at the top position of a chin-up, and slowly lower yourself down to the bottom in a five-second count. Do three reps at the end of each set of your usual chin-up work, or if you can't do a chin-up then start with three sets of five negatives and each week try to add a rep each set. Retest your chin-ups every four weeks and note the improvements.
Raise the bar
After you've built up your base strength you can start on the curls and lay down some serious muscle. Once a week after your chin-up or row work, try curls with dumb-bells that you can lift for a maximum of 10 reps. "Start with three sets of eight and add one rep each week until you can do 12, then move up to a heavier weight and start back at eight," advises Bathke. Use strict form with knees locked and no torso momentum.