My HRV is low — should I still run today?

Why one reading doesn't decide anything

HRV is noisy by nature. A late dinner, one glass of wine, a hard workout the evening before, or simply a slightly different measurement position can push a single morning reading below your normal band without meaning anything about your recovery.

That is why the comparison that matters is never today versus yesterday — it is today versus your own rolling 7-day average. A single dip below that average, with everything else normal, is a yellow flag at most: run, keep it conversational, and look again tomorrow.

When a low HRV is a real signal

The pattern that deserves respect is persistence plus agreement. Watch for these together:

• HRV below your 7-day baseline for 2–3 consecutive days
• Rising variability between readings (your numbers swinging more than usual)
• Sleep under 6 hours or badly fragmented the night before
• Resting heart rate 3–5+ bpm above your normal

What to actually do

One low reading: run as planned if the day is easy; if it's a hard day, do it but be honest about effort. A 2–3 day cluster: keep the run, remove the intensity — the workout isn't wrong, the timing is. Move the quality session 48 hours and the training week still works.

If low HRV comes with feeling run-down, a scratchy throat, or a resting heart rate that keeps climbing, treat it as illness knocking: take the rest day. One easy day costs you nothing; pushing through the start of an infection can cost weeks.