Intense Couplet Workout

This was a pretty intense workout this morning.  Here it is, several hours later, and my shoulders are still fatigued feeling.  There were several intervals throughout the workout where I cheated and quick a second or two early.

Workout: 5 Couplets, Each couplet repeated 3xs before proceeding to the next, Intervals 10/30

Couplet 1:
1a. Explosive Star Jump
1b. Walk Out Push Ups

Couplet 2:
2a. Pike Leg Switch
2b. Elbow Plank Hops

Couplet 3:
3a. Side to Side Lunge Jump Touch Downs
3b. Super Girl Push Ups

Couplet 4:
4a. Triple Sumo Squat Jumps
4b. Elevated Cross Knee Tucks

Couplet 5:
5a. Super Low Oblique Hop Squats
5b. 1- Arm Pike Press Ups

Workout Stats:20 Min.
Avg HR-149
Max. HR- 177
Min. HR- 85
Time Above- 16:52
Time In- 1:32
Time Below- 2:13
Burn- 14g, 111.3Kc

Hmm, I'm kind of surprised at the HR stats as I recorded them here.  They aren't as high and intense looking as I thought they would be.  I think it may be because this workout was really fariguing my muscles but not necessarily my heart???