I had a great Chief Petty Officer who was a senior enlisted advisor in college; went through Hell Week 3 times and Dive Phase twice before he finally became a SEAL, tough SOB. His advice to the aspiring SEALs on BUD/S and Hell Week was, "How do you prepare for a kick in the nuts? You don't, you just brace yourself and take it as it comes." The guys I went to college with who did well at BUD/S were just fucking tough.

I would suggest these focus points:

-Swimming and running for conditioning is important, but make sure you focus on swimming more efficiently (combat side-stroke or breast stroke, whichever is your stronger stroke), and water confidence: ditch and don drills and bobs in a deep (15 ft +) pool.

-Strength train 2 days out of the week doing the standard A/B split and 3 sets of 5 instead of 5. Make modest increases if you can, but your strength is probably pretty good for most guys starting BUD/S already so don't get greedy.

-Conditioning is important, obviously, I would suggest 3x a week doing hard conditioning (one week do 2x in the pool and 1x running, the next week do 2x running and 1x in the pool) and spending time in the pool every day.

-Use short, fast repeats after working on your stroke (say 1-2,000 m working the side stroke as a slow pace, then 10x100 m or 5x200 m as fast as possible with 3-5 min rest) for swim conditioning.

-A heavy ruck run every other week (5-6 miles) and run/swim/run routines work well for run conditioning.

Just make sure you're rested and have some decent padding (~2 wks) before Indoc (being overly lean does you no good at BUD/S, you won't keep it on, but you gotta EAT at BUD/S like your life depends on it). You don't need to be at the front of the pack during Indoc; just don't be last and don't give up. Good luck, too.