I ran into a couple folk like you, skinny as a rail, had one guy put on 25 pounds of muscle. PT wasn’t all punishment, it was just one more challenge to meet.
The midrats is what got me.. and the food in the barracks dispensers.. 1st MAW .. 1st fed .. 8-]
DI's are some sick mofo's, that's for sure. They pinned me to a guy who was 30 pounds overweight. I was on double rats, he was on half rats.
I thought I was going to have to fight him once to keep him away from my chow. LOL!
He did it, though. He lost the weight and by the time we headed off for AIT we were lean, mean fighting machines.
After I got through Scout School the instructor told me "It's always you skinny, quiet f****** we gotta watch out for. The big weightlifter types drop out in the first couple of weeks, usually."
For some odd reason I was pretty proud of myself that day.
L