Roadking- My son is also prepping for Beast, and now that Track and Field is over he is on "two a days" also, we get up together at 0530 and he runs, and I walk. we are putting in ruck work 2x a week, mostly to break in boots and for him to see what it feels like. He does Push ups and Sit ups (Core) work out in the afternoons, with Bench press. The Push Up work out is a pyramid of sets, starting with regular, wide arm, one set of "diamonds" then back down with Wide arm and then regular. I will tell you that the Army Standard for all Combat Skill badges (except Airborne school) is a 12 mile Road March in 3 hours with Ruck (normally 35-45 lbs depending on Badge), this includes Helmut, Weapon (8-10 lbs) and Vest or "load carrying equipment" which has the canteens, hydration system or whatever they call it now. These are the schools or Qualifications such as Air Assualt, Expert infantry Badge, Expert Field Medical Badge, Ranger etc. If he is going to build up to the 12 miler, most Cadre will tell you to be at the 6 mile mark no later than 1 hour and 20 minutes. WHen I went to Air Assualt School we had a Lieutenant "run" the 12 mile in 1 hour 43 minutes! but He was a Tri-athlete. I don't reccomend running in boots at all. Don't know if you have access to a Kevlar Helmut, or fashioning some type of Stick with weights on it to simulate a weapon, but these two items alone bring a whole new level of pain and discomfort and challenge to just "rucking" with pack on your back...... Having done 12+ of these when I was a Basic Training Drill Sergeant at Fort Jackson back in the day (part of the reason I don't run anymore! LOL!) It' was always interesting to watch which Soldiers would just gut it out and which ones would just fall apart. As some of the others posted, I would really be careful with that Cross-fit, pick the right exercises, I would imagine that Rope Climbing would pay dividends at Beast, but stay away from back lifts, And a Strong core (Abs) really helps for Rapelling and Push ups, as you have to be in a good "L" shape to rapell. That's my 2 cents, Good Luck and we'll see you at USMA!!