Ever since I started slinging my right arm and shoulder have been stronger than ever. I'm also more agile in that arm. I need to start working my left arm more now because my parents can actually tell the difference in size between my arms. Slight but still there.

I've also been building alot more. So that helps my arm and my hand strength. I play mercy better than ever!!
Start doing more sit-ups and pull-ups and I'll be the champ!

Anyone else experiance this and other positive things?

P.S. Sorry if this sounds real vain, but hey, it's pretty cool  8)

I have noticed some bulking-up of my slinging arm...nothing too visible...but a difference nonetheless.

If you see an army of bulky-armed, lopsided soldiers you better look out!!

Iv'e noticed as well that my right arm is a tiny weiny bit bigger and also the accuracy of my right arm has improved a lot.  In every paper ball fight i am the Champ

One day while helping to move furniture at the house, my mom looked over at me, and saw my right bicep, and said "Jesus Christ, boy, what happened to your arm?" I thought maybe I cut it or something so I checked it over, and didn't see anything. She said ,"With muscles like that, maybe you ought to be lifting the table by yourself." I smiled and told her, "It's the slinging." She laughed at that one. As well, I've found that my hand-eye coordination has improved, if slightly. Still can't hit anything worth a d*** with the sling, though. Oh well, practice makes perfect, eh?

I haven't noticed a deference in arm size from slinging, but i have a phiysical active job and i lift weight too.