Dolld: I'm not a Marine, but I've been PTing with the Marines at my unit prepping for OCS this semester (3-4X a week from 0600-0730)and here's a word to the wise:
get used to PT with Boots and Utes: In other words, spend 20 bucks on a pair of jungle boots (you can get them at most surplus stores), get some comfortable insoles, and run in them as much as possible. We do a lot of 4 milers, 3 mile pack-runs, fartleks, etc. The Marines on this forum will certainly correct me if I'm wrong, but we do very little in actual PT gear and tennis shoes. That leads me to believe that you won't do much PT in PT gear and tennis shoes at OCS.
The way I get in shape for their humps (they train with a min. 40lbs pack, kevlar helmet, weapon, and full cammies sleeves down) is I practice on a treadmill at a minor incline at about 4.5 mph. That's a shuffle/run for me (I'm 5'4"), but its the pace they take when they do their humps. So far they've done a 6mi, 8mi, 12mi, and they've got a 15 miler scheduled in April. I can barely keep up for the first mile or so, so I'm sticking with the treadmill until I can keep the pace up for at least an hour or so.
Oh...BTW, I'm Navy, I just PT with the Marines for fun. Any questions about boats, water, or scuttlebutt...just ask.
Yut...kill.
<I SWIM 'CAUSE I'M TOO DAMNED SEXY FOR SPORTS THAT REQUIRE CLOTHING>