Mid foot cleats = lower HR??

Not sure if this was a fluke or what but in doing my 3 x 10' FTP intervals yesterday, I decided to make a change for the last interval - moved my Look cleats as far back as they would go and compared the data.

Interval #2

Pavg - 264W
Cavg - 86 rpm
HRavg - 152 bpm
SPavg - 20.8 mph

Interval #3 (moved cleats back)

Pavg - 265W
Cavg - 84 rpm
HRavg - 147 bpm
SPavg - 20.5 mph


Hmmmmm........