Barbell biceps curls are perhaps the best mass building exercise for the biceps.
Since both wrists are supinated the biceps are being effectively isolated for
the duration of the motion. The bar biceps curls are one of the most common
exercises for those just starting out in weight training because the biceps are
probably biggest vanity muscle. While strong biceps have their benefits, barbell
biceps curls are primarily for those looking to aesthetically improve the shape
of their biceps and can be left off most workout routines where weight loss is
the primary goal.