Recovery
How to read your daily readiness score
By VivFit TeamPublished Updated 8 min read
A daily readiness score is a single number, usually out of 100, that estimates how recovered your body looks this morning compared with your own recent normal. It blends overnight signals such as sleep, heart rate variability (HRV) and resting heart rate. Use it as a prompt to adjust today's effort, not as a verdict on you and not as a medical measurement.
That is the whole idea. The rest of this guide is about reading the number sensibly, because a score only helps if you know what moved it and what you are going to do about it.
What is a readiness score?
A readiness score is a summary. Your phone or watch gathers a handful of signals from the night, compares each one with your personal baseline, and folds them into one figure so you do not have to inspect three charts before breakfast.
There is no standard formula. Every app weights the inputs differently, which means a 78 in one app and a 78 in another are not the same statement. The useful comparison is always you against you: this morning against your last few weeks.
Most scores draw on some mix of these inputs:
- Heart rate variability overnight, compared with your usual.
- Resting heart rate, compared with your usual.
- How long and how steadily you slept, and whether the last few nights have added up.
- Recent training load, so a hard week counts.
- A short subjective check-in: how tired, sore or stressed you feel.
VivFit's readiness score uses signals of this kind, built from whatever you choose to share from Apple Health or Health Connect plus a quick daily check-in, and it shows the reasons beside the number so you can see what moved it.
The three signals behind most scores
Heart rate variability (HRV)
HRV is the variation in the time between consecutive heartbeats. A healthy heart is not a metronome: the gaps between beats shift constantly, and that variation reflects how your nervous system is adjusting to physical and mental demands (Shaffer and Ginsberg, 2017 (opens in a new tab)).
Two things matter for reading it. First, baseline HRV differs between people with age, sex and how it is measured, so your number means little next to a friend's. Second, a single night is noisy. The same review notes that recording length, age and sex all affect baseline values, which is one more reason trends over days beat any single reading.
Researchers who study training status make a related point. A review of heart-rate-based monitoring concluded that changes should be judged against measurement error and the smallest change that is worth caring about, and that these measures work best alongside training logs and questionnaires rather than on their own (Buchheit, 2014 (opens in a new tab)).
Resting heart rate
Resting heart rate is how fast your heart beats when you are calm and still. The NHS says most adults sit between 60 and 100 beats per minute, that the fitter you are the lower it tends to be, and that athletes may be at 40 to 60 beats per minute or lower (NHS, how do I check my pulse? (opens in a new tab)).
Notice how wide that range is. What matters for readiness is your own baseline. If you usually wake at 54 and today you are at 61, that gap carries more information than whether 61 is inside the textbook band.
Sleep
Sleep is the input people understand best and manage worst. A joint consensus statement from the American Academy of Sleep Medicine and the Sleep Research Society says adults should sleep seven or more hours per night on a regular basis to support optimal health (Watson et al., 2015 (opens in a new tab)).
The word that matters is "regular". One short night usually dents a score a little. A run of short or erratic nights moves it a lot, which is exactly what it should do.
How to read the number
Start with the direction, then look at the reasons. A score that is a few points off is noise. A score that sits well below your normal for several days, with the same signals pointing the same way, is worth acting on.
| What you see | What it may mean | A sensible response |
|---|---|---|
| Score near your usual; HRV and resting heart rate at baseline | You are recovering as normal | Train as planned |
| Score down, but only sleep is short | One poor night, not a trend | Keep the session, trim volume or intensity if you feel flat |
| Score down for several days; HRV lower and resting heart rate higher than usual | Accumulated load, stress or a poor sleep run | Ease off for a few days, protect sleep, favour lighter sessions |
| Score up after a few easy days | You have recovered | A good day to push, within the plan |
| Numbers far outside your normal and you feel unwell | Not a training question | Rest, and speak to a doctor or pharmacist if it persists |
Two signals pointing the wrong way together are a stronger cue than either one alone. That is a rule of thumb rather than a research finding, but it matches the advice above to read measures in combination.
Four habits that make a score useful
- Compare weeks, not mornings. Look at the last seven days against the last few weeks. A single bad morning tells you almost nothing.
- Measure the same way. Wear the watch the same way, at the same time, and check in at a similar point each morning. Inconsistent measurement creates movement that is not physiology.
- Add how you feel. The score can be high while you are heavy-legged, and low while you feel fine. Your own check-in is data too, and the monitoring research above recommends pairing numbers with questionnaires.
- Do not chase it. Going to bed anxious about tomorrow's number is worse for your sleep than a mediocre score. If tracking starts to feel stressful, switch the number off for a fortnight.
What a low score does not mean
A low score is not a diagnosis, and it is not a reason to feel behind. These measurements are estimates from consumer devices, and accuracy depends on the device, how you wear it and how much you move in your sleep.
It also does not mean "do nothing". The NHS recommends adults aim for at least 150 minutes of moderate activity a week, plus strengthening work on two or more days (NHS physical activity guidelines (opens in a new tab)). A low-readiness day can still be a walk, some mobility work or a shorter session at an easier effort. The point is to match the day, not to cancel it.
If your resting heart rate is unusually high or low for you, your pulse feels irregular, or you feel unwell, that is a conversation for a doctor, not an app.
How VivFit uses readiness
On VivFit's Today screen the readiness score sits beside the reasons for it, so you can tell whether sleep, recent training or your check-in did the moving. The rest of the plan then follows: slept badly and the session eases off, busy week and it gets shorter. You can see how a day adapts on the home page.
The same principle is behind progressive overload: you want enough challenge to keep improving and enough recovery to absorb it, and a readiness score is one way to check the balance. VivFit is coming soon to iPhone and Android, and you can join the waitlist for launch news.
Frequently asked questions
What is a good readiness score?
There is no universal good number, because scores are built from your own baseline and each app uses its own formula. A good score is one that is at or above your usual range. Learn what normal looks like for you over a few weeks and treat movement away from it as the signal.
Is HRV or resting heart rate more important?
Neither is more important on its own. Heart-rate-based monitoring works best when several measures are read together and set alongside how you feel and what you have trained. A change in HRV and resting heart rate in the same direction is more convincing than either alone.
Should I skip training when my readiness is low?
Not necessarily. A low score is a reason to consider a lighter or shorter session, more sleep or an extra rest day, depending on how you feel. Staying active still counts towards weekly activity guidelines, so an easy walk is a fair swap for a hard session.
Do I need a wearable to get a readiness score?
You need some signals. VivFit can read sleep, steps and heart data from Apple Health or Health Connect when you allow it, and the daily check-in works without any extra device. Which signals feed your score depends on what you choose to share.
Is a readiness score medical advice?
No. It is general wellness information built from estimates. It cannot diagnose or treat anything. If something feels wrong, or a number worries you, speak to a health professional.
Sources
- Shaffer F, Ginsberg JP. An overview of heart rate variability metrics and norms (opens in a new tab). Frontiers in Public Health, 2017.
- Buchheit M. Monitoring training status with HR measures: do all roads lead to Rome? (opens in a new tab) Frontiers in Physiology, 2014.
- Watson NF et al. Recommended amount of sleep for a healthy adult: a joint consensus statement of the AASM and SRS (opens in a new tab). Journal of Clinical Sleep Medicine, 2015.
- NHS. How do I check my pulse? (opens in a new tab)
- NHS. Physical activity guidelines for adults aged 19 to 64 (opens in a new tab)
This article is general wellness information, not medical advice. Check with a doctor or other health professional before changing how you train or eat, especially if you have a health condition. Reviewed against the linked sources on 9 October 2026.
