Toning Arms

I love Orange Theory because it has gotten me to LIFT HEAVY and push my limits. But now I am finding myself (mostly my arms) bulking up. Now I need to be in the toning phase and while I have a gym at work with weights and some machines, I am curious if the theory "more reps, less weight" is really going to help me tone my arms. Any suggestions on certain work outs that can help tone the arms without lifting heavy? I also have a peloton at my apt complex and when I do the 45 min spin and arms, after I get done with the workout , my shoulders are usually burning and I am only using 2lbs! Any advice is welcomed :)