As ironic as it may seem, one of the biggest mistakes people make when trying to get bigger arms is to focus only on their arms.
By focusing on large muscle groups - your back and legs - you can achieve better gains in your smaller muscles (arms), while becoming stronger and bigger overall. After all, friends don't let friends skip leg day.
The testosterone factor
In order to get bigger, more muscular arms, one of the keys is to produce more testosterone.
This doesn't happen through grunting, eating massive amounts of red meat, or pounding down a few cold ones while flipping through Maxim with the guys, it comes from putting stress on your body's biggest muscles.
What does that mean?
Deadlifts, squats, pull-ups - multi joint movements that engage multiple large muscle groups - are essential to building bigger arms. Your body undergoes stress from these movements and produces more testosterone to overcome the stress, which in turn, builds muscle.
It may be hard to believe, but even if never did another bicep curl or tricep extension, but focused on heavy lifts that target large muscle groups, your arms would still get bigger because of the testosterone factor.
Train the whole body
Still living in the late-1990's and working out using a "Back and bi's" and "Chest and tri's" workout schedule, while frequently skipping leg day and not knowing how to deadlift?
If you want to get stronger, bigger, and more muscular, work on making your whole body stronger. If your legs are stronger, they'll enable your arms to be stronger. If your back is stronger, your arms will have the potential to handle heavier weights.
The body is meant to be interconnected, not spot-checked. Just like you shouldn't try and lose weight in one specific body part, your training shouldn't be focused on singular body parts.
By focusing on compound movements (squats, deadlifts, cleans, snatches), rather than individual muscle groups (bicep curls, tricep extensions), you can work on your body's bazookas, while improving your water guns.
Why spend time focusing on the water guns when you could work on both at the same time?
Get bigger arms
For more about how working your big muscles will make your little muscles bigger, visit Rob King Fitness.