3 months ago, I received a brand new seabag from a coworker. I took it to the wash by my house, filled it with sand, took it home, and got it to weigh 45 pounds. Now I use it to ruck around with. Are there any other workouts I could be doing with this? Any other similar "penitentiary" or I guess "FOB" -style workouts you guys have used that worked out well?