When Should Overnight or Shift Workers Measure HRV?

You may have read that we recommend taking your Morning Readiness reading first thing in the morning after waking up. But what if you don't wake up in the morning? While there is no official recommendation on when to measure, there are a few options. 

You could choose to always measure after the longest sleep. It will likely show some big swings when going on/off shift or when the shift schedule changes. But you'll get to see a longer-term trend this way.

Or if, for example, you're a night shifter and do 4 days on/4 days off, then you could choose to only measure HRV on the days off (natural day morning) and skip the 4 days on.

It's worth picking one method and sticking with it for several weeks to see how it works for you before trying the other.