Here's a super simple rule to follow when you do your next set of curls.
To work biceps, nothing beats the curl. But to work your muscles in the most complete way possible, feel free to change the movement, to rotate, or to make the movement in reverse. The more your muscle works from different angles, the more likely it is to grow in the way you want it to.
Beyond this little tip, this video shows us that it is very important to know your body. By simply analysing which muscle moves when you do a movement, you can predict which exercise will work the right muscles.
Check out the video above to see this neat trick in action!