HRV, sleep and readiness: when to push and when to back off

Your watch or ring probably shows a readiness or recovery score every morning. Behind it are a few signals: heart rate variability, resting heart rate and sleep. They're useful, but only if you know what they can and can't tell you.

What the signals mean

• Heart rate variability (HRV): the small variation in time between heartbeats. Higher than your normal usually means you're well recovered; a clear drop can mean stress, illness, poor sleep or a hard training week.
• Resting heart rate: a few beats above your normal for several days often means you're run down.
• Sleep: the simplest one. Less than you need, and your strength and focus suffer the next day.

Compare against yourself

HRV numbers vary hugely between people, so your number against someone else's means nothing. What matters is today against your own last few weeks. One low morning is noise. Several low mornings in a row, together with a high resting heart rate, is a signal.

What to do with it

• Signals good, you feel good: train as planned, or push your main lift a little.
• Signals low, you feel fine: train, but keep the first heavy lift a step lighter and see how it moves.
• Signals low, you feel bad: make it an easy day: fewer sets, lighter weights, more reps in reserve.
• Low for a week: check sleep, stress and food, and consider a deload week.

Tip: Your logbook is a readiness signal too. If the weights feel heavy and your reps drop, that matters more than any score.

How Liftsmith uses it

Liftsmith builds a daily readiness score from your training first: how recovered your big muscles are, how many days since you last trained, whether you hit your target reps and how your sets felt. With Pro, it also reads sleep, HRV, resting heart rate and breathing rate from Health Connect or Apple Health. Today then shows a push, as planned or go easy call with the top reasons behind it, and you can always override it.