You want to go through a full range of motion—if you feel discomfort in the elbow then what you would do is lower the weight ... sure there's not too much flexion in the wrist.

which require more lat strength and elbow flexion. Your biceps are guaranteed to be popping after you've done a couple of chin up sets. Plus, you can increase the difficulty by wearing a weight ...

Hinge joints allow flexion and extension only. Flexion – bending a joint. This occurs when the angle of a joint decreases. For example, the elbow flexes when performing a biceps curl.