Step Workouts

Hi everyone!

It might be a silly question, but am I the only one struggling to lift heavy for step strength workouts because my arms can only take so much weight? I end up lifting hardly any more weight for step ups than I do for curls because my arms get so tired after a couple of sets. That's so frustrating! My legs could lift heavier but my arms won't let them...

I do a lot of upper body routines and like to challenge myself with "heavy" weights, but my arms (and my hands) somehow can't stand more than 50 lbs total for more than a couple of sets of step exercises...

Any tips to solve this problem? Thanks.

Edited