the standard bicep curl grip (supinated grip) targets the visible muscle on your upper arm, but if you reverse the grip with your palms facing down (pronated grip), it primarily targets your forearms.

But these changes bring other benefits too. "Firstly, the shift from an overhand grip to a supinated one means you are moving ...

A bicep curl uses a supinated grip (also known as an underhand grip), while the hammer curl uses a neutral grip (where your palms are facing each other). It’s a subtle change, but it makes a big ...