Is "HR Lag" actionable?

Training
1

Hello,

I usually don’t think about it much but today my HR Lag was ~45s vs. the typical ~30s for similar intervals workout.

Is this something to keep an eye on? What might it indicate?

Thanks,
Alex

2

Personally I tend to think of heart rate as a response metric, so a delay in lag can indicate fatigue or illness. Your best to compare it with RPE and go from there, so did the workout feel harder in which case something to worry about. If not more coffee tomorrow :wink:

3

Funny thing: I just noticed now that Garmin’s software has marked today as “Peaking” (not sure at all they take HR Lag as a parameter - my guess would be just Power/HR ratio).

I am really confused. I could see two conflicting scenarii:

  1. HR Lag is increasing: your heart doesn’t need to pump nearly as hard when you start an effort.
  2. HR Lag is increasing: you’re tired and your heart is struggling to perform when demand arises and stays elevated after an effort.

I am thinking like you, @Adam, that scenario #2 is more plausible but I don’t know if there are exceptions.

1 Like
4

Hmm, I’ve never heard of scenario 1 as a possible explanation but I’ve also never researched it. I’d be more inclined to think its #2. CNS fatigue leading to a delayed HR response.