What is (Pw:Hr), Aerobic Decoupling?
Aerobic Decoupling is a ratio between Normalized Power and Heart Rate between the first and second part of your workout.
(NP1/HR1) - (NP2-HR2)/(NP1/HR1)
NP1 – Normalize Power from first half part of the workout
NP2 – Normalize Power from second half part of the workout
HR1 – Heart Rate from first half part of the workout
HR2 – Heart Rate from second half part of the workout
How to Use it?
It can be used as a “rate of fatigue”. It could be used during long aerobic workouts, long climbs or time trials. Aerobic Decoupling reflects how heart rate is reacting to our input which is power.
For the best result in tracking Pw:Hr it is good to check it during steady, below threshold workouts, going over your FTP is not the best reflection because the reaction of power and heart rate is way different timewise.
A good example can be endurance 2,5 hours workout with 1-hour tempo zone interval. Going as steady as possible, we can check the results of Pw:Hr. The goal is to be below 5%, if it is lower then 5% it is good information that our body can handle this type of effort and we can move to zone 4 workouts. If it is higher then 5%, we still should spend more time on improving our endurance and tempo zone or take a little break it can be a sign of being overloaded. If you did this type of workouts before at this period of preparation and your Aerobic Decoupling was lower then 5% it is a sign of being tired and overloaded with your training plan. Take a break!
1. In most cases, it’s very difficult to control or make the riding only ‘aerobic endurance’ Because we meet uphill or downhill. Then, we cannot measure EF or Decoupling?
2. Whenever I check Training Peaks analysis, I can see those figures even if my workout was not totally ‘aerobic’ Then, how should I understand the figures? Does TP calculate EF or Decoupling only as extracting my aerobic riding during the whole workout? or are the figures calculated simply considering my whole workout performance?
Actually, I got a chance to hear from Joe about it and yes this is true, but we can “extend it” to zones 3 and 4 as long as a workout is steady. This is the most important thing, it should be as steady as possible (VI should be 1 or very close).
If it is interval training, group ride or race, you shouldn’t be even looking at EF or Pw:Hr!
Another thing we could use it are longer steady uphills, so if you are doing 4×20 min uphill you can compare EF from those intervals, but something they have to be as steady as possible.
No, unfortunately, TP in not pulling just your aerobic zone, that is the way those numbers are not accurate during interval rides, group rides, etc.
I hope it helps with a better understanding of the subject.