Understanding recovery

I’ve noticed a recovery pattern that I cannot explain. Any thoughts?

The pattern is:

  • in the first two easy sessions following a hard session, the power to heart rate ratio in the first session is higher than in the second one.
  • the duration i can hold HR zone 2 comfortably is shorter during the first session.

I don’t understand why my power/hr ratio is better in the first easy session.
The only theory i could produce was: type II kicks in right from the start because type I’s are fatigued. Glycogen is low, so the uncomfortable feeling kicks in quickly.

This pattern emerged both when the 1st easy session was on the same day as the hard session, as well as when it was planned on the next day.

Practical example:

  • sprint training on Monday
  • easy on Tuesday (10 min z1 warmup, z2 for as long as it feels good, 5 min z1, another z2 for as long as it feels good, 5 min z1, cooldown)
  • easy on Wednesday (same structure).

Any thoughts?

Are you taking about Aerobic Decoupling in training peaks? Or just HR at a given power?

Power at given hr. This is not a case of decoupling.

Could you share examples. Power + HR?

If you’re saying HR is higher closer to the harder session, that makes sense. You’re more fatigued (nervous and muscular). When this happens it’s a sign I should reduce effort to keep HR in zone or that my hard session the day before was too hard. To me, if I can’t hit easy zone ranges and HR targets, I did too much the day before or over the last couple days

However I’ve seen it go the other way as well. Depressed HR following a hard session. For me this is an indication I need to really back off my training and fully take the day off or go short and super easy.

Here is the data:

Left: the sprint training on Monday
Middle: dynamic duration z2 on Tuesday (felt heavy after 5 min, but better power/hr)
Right: dynamic duration z2 on Wednesday (can sustain, but low power/hr)

Everything looks pretty close. Your avg power is lower the first easy day, but your first z2 interval is 10% higher than on the second day and your second is 10% lower than the second day.

However what I can’t tell from the charts is how long your doing each interval.

Maybe try to duplicate the same power / duration over the two easy days (even better if you use ERG). If your HR is lower the first day, then that tells me you’re likely pushing too hard overall or the day before.