hammer curls

when doing hammer curls is it better to cross in front of your chest or keep your fists straight up and down?

It depends on what muscle you plan on targeting. Because the position of the palms the bracjialis muscle is the prime mover rather than the biceps when yup do hammer curls… If you want to target more biceps with the hammer curl then do cross body hammer curls such as crossing in front. If you want to stick to more traditional and target more brachialis then go straight in front.