Think it also depends on whether you had open or laparoscopic surgery.
I had open surgery and even prior to my J pouch creation, I decided I’d take a year off from all activity, including weight training but even after my takedown, there was no way I could return to training within 2 months, especially as I had a open wound at my old stoma site.
It was at least 8 months after takedown before I felt well enough to return to training.
Prior to surgery, i had good a core condition which helps reduce the risk of a hernia.
I had a colostomy bag for 9½ years and for at least 5 years before the J pouch surgery , as well as core strength workouts & weight training, I also participated in an intense form of self defence training.
I think the concern in regard to weight lifting after j pouch surgery, is performing Olympic style deadlifts due to the internal bearing down pressure that’s required during such a lift, which can even cause embarrassing accidents to those not even afflicted with a bowel condition.