a quick follow up on the data I shared last week covering HRV responses to back-to-back high-intensity workouts

for the first three double sessions (high intensity run followed by high intensity ride), I had increased load (e.g. I went from 12 to 24 minutes of high intensity) and had a suppression in HRV following the second hard session, showing difficulties in re-normalizing from this harder than normal stimulus

nothing to worry about, as data re-normalized the day after an easy workout, hence there was no chronic suppression and no need to further adjust my plans. However, we do expect changes over time as we get fitter or better at dealing with a certain stressor

at the fourth double high-intensity session, once I had maximized the volume of the stimulus and therefore kept it the same as in the prior session, I had a positive response. These are simple ways to use the data without necessarily making adjustments, but allowing us to learn how the body is dealing with training, and how it is progressing in its ability to assimilate it

see also this blog that I have updated: marcoaltini.substack.co…

needless to say, we need to look at the physiology to appreciate these changes, not at made-up scores (e.g. readiness or recovery, which confound the response with behavior, such as sleep time or activity level, and therefore do not reflect our body’s response)