Not a gym exactly, but sport...
Dry Ski Slope, West Midlands, about 1989. I am seven years old, and my parents have forced me out on a rainy Saturday to repeatedly snow-plough down about 100m of dirty carpet. I'm going with them to Italy a week later on only my second ski trip, and they insist on me getting some practice.

Much as I liked skiing in the mountains, this was not my idea of fun as I was soaked through and would far rather have been at home. So there I am, mind elsewhere, when I let slip one of my ski-poles.

I don't know if any of you have seen a dry ski-slope, but the surface is made of a sort of grid, like this

www.farminguk.com/images/news/4282_1.jpg

The pole fell forward, the handle went into one of the holes, the tip end flicked up in the air, and I skied straight onto it, with the handle braced in the hole providing resistance, and managed to rip open my scrotum.

My mum thought I was just moaning because I wanted to go home and made me do another 2 runs before I pulled out my salopettes to show her that my pants had turned red and the blood was running down my leg. She relented and took me to hospital, where I waited in pain for 45 minutes before a very tired and nonchalant looking Doctor stitched my ballbag closed again.

Yes, it hurt. The salt-baths I had to take for weeks afterwards hurt too. Plus the fact you don't get many opportunities to show off the fairly cool scar (the most memorable exception being the Doctor I later had a fling with, who stopped mid fellatio to commend the quality of the stitching)
(SnowyTheWereRabbit the Leporid from Hell, Thu 9 Jul 2009, 14:11, 2 replies)

fellatio?
on a seven year old?

shocking!!
(Cancer Joy was short lived, Thu 9 Jul 2009, 14:17, closed)

That
gets a click for the doctor comment alone!
( Jimbuktu See? Right here, Thu 9 Jul 2009, 14:58, closed)