JJ Virgin breaks down how to build arm muscle: progressive overload. Your muscles only grow when you force them to do more than they're used to. Low-intensity familiar movements won't cut it unless you're completely out of shape.
Settle down, it'll all be clear. Here's the important truth about building muscle. It's called progressive overload. In order for you to build muscle, you have to do more than what you're used to so your body adapts and gets stronger and builds muscle. So, just doing this unless you're totally deconditioned is not going to make you stronger or build muscle.
