Interval ride

The main set of today's ride included 40 minutes at 160-165 bpm with a few minutes rest inserted. A few minutes into the first interval I decided to break it up as 4 x 10 min., with 1 or 2 minutes between intervals. During the third intervals, I though my power was dropping a bit, so I added another rest minute 5 minutes into the fourth set. I felt good, although I kept a slightly higher than normal cadence that tired out my hip flexors. I swear a high cadence on the trainer is tougher than the same cadence out doors.

Stats:
0-10 - 160 bpm, 285 W, 86 rpm (I worked my HR up so it was 157 at the start of the set)
10-20 - 161 bpm, 272 W, 85 rpm (HR started low from rest from for the rest of sets)
20-30 - 162 bpm, 259 W, 84 rpm
30-35 - 160 bpm, 264 W, 84 rpm
35-40 - 161 bpm, 251 W (ugh), 84 rpm

Basically it went from great to sub-par over the course of the set. Still, I feel good and rested.