Bodyrock.tv: My Buns Hurt Workout-2

My buns definitely hurt after this workout. First time did it in April so it was time to revisit it again!

Workout breakdown:

Part 1: 40 sets of sandbag lunge back, press up and squat leg lift (alt.side) (Time Challenge)
I used my 15lbs dumbbell b/c the backpack was too bulky for doing press up. I didn't beat my old time, because I think I might sprain my left shoulder sometime this week..not sure what I did though.
Time: 4:34 (old : 4:07)

Part 2: Interval training 5 sec off/15 sec on for 12 rounds of Rocket Launchers

(1-2-3 Jump up)
4-7-7-7-7-7-7-7-7-7-7-6 (old :6-6-6-5-5-5-5-6-5-5-6-5)

Part 3: 20 sets of Kick Ups (Time Challenge)
Time: 3:31 (old 4:10 - incorrectly)
This time I did it correctly!

Part 4: Interval training 10 sec/10 sec for 12 rounds of Jump Lunge/Mountain Climbers non stop

Roughly I did 9 jump lunges at first interval and between 3-5 afterward (mixed with step back but I kept myself moving and did about 15-15 Mountain Climbers. This one is still a super burn out!
(old: I did roughly 5 Jump lunges at first intv and only between 1-3 afterward and 5-10 Mountain Climbers. Super burn out! I think I took way too many breaks, especially for jump lunges)

Plus:
5-5-5 1 leg assisted reverse push up - I am working on doing reverse push up with both legs straight instead bent.
10 Burpees