Respiratory rate

What it is

Respiratory rate is the number of breaths per minute. Wearables usually measure it overnight, when exercise, posture and caffeine aren’t pushing it around, and then compare each night with your usual range.

Why it matters for training decisions

For most people overnight respiratory rate changes very little from night to night. That stability is what makes it useful: a clear rise above your normal range is easier to spot than a change in a noisier metric like HRV. WHOOP added respiratory rate to its Recovery score in 2020 and says it mainly affects the score when it’s elevated, rather than every day.

A higher-than-usual reading isn’t a diagnosis. Illness, heat, altitude, alcohol and a hard late session can all play a part. Treat it as a reason to look at your other signals, and how you feel, before a hard day.

How wearables measure it, and the limits

Apple Watch measures respiratory rate while you sleep when sleep tracking is on, and the Vitals app shows it against your typical overnight range. WHOOP derives it from the small rise and fall in heart rate that happens with each breath. Both work best with a well-fitted device worn every night. Apple notes that its Vitals measurements aren’t intended for medical use.

How P247 uses it

P247 reads overnight respiratory rate from Apple Health along with your other overnight data. It isn’t one of the inputs to P247’s recovery score.

This glossary is general information to help you understand your training data. It isn't medical advice, diagnosis or treatment. For injury, illness, medication, blood test results or any health concern, speak to a qualified health professional.

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