I have been dancing for cardio workouts and it mostly involves arm movements. Nowadays my arms seem to look slimmer but they feel lighter as well. Also, I feel like I can't throw a punch or perform an elbow. When I try and throw a punch, it feels weak and that I didn't add any force into it. Plus, sometimes I feel that I can't fight at all and I feel less aggressive as well, even I have gotten into a fight once. I don't know what seems to be the problem is. What can I do to fix this? Should I take up a boxing class?