It does as long as it isn't as much to the point that it slows you down significantly. You can try it out by punching a heavy bag with and without a 3 lbs dumbbell in your hand. 3 lbs won't slow you down, but your punch will be much more powerfull.
I train with weights and big gloves all the time, that's not the same as having thirty pounds of gut hanging off your belly though. I realize subcutaneous fat distributes itself all around your body but it never looked like he had a ton of fat on his arms to me...
Everybody good, plenty of slaves for my robot colony?