LodestarYour Fitbit already records the signals a recovery score needs: overnight heart rate variability, resting heart rate and detailed sleep. What it doesn't do is pull them together into one clear answer to "how ready am I today?" Here's how that works.
What goes into a recovery score
- Heart rate variability (HRV) while you sleep. Higher than your usual generally means your nervous system has recovered. More on HRV.
- Resting heart rate. A few beats above your normal can have many causes, from fatigue, alcohol or heat to feeling run down. Why it rises.
- Sleep: how long you slept against what you need, and how much of it was deep and REM sleep.
- Supporting signals like breathing rate, skin temperature and blood oxygen. They rarely move, so when they do, it's worth noticing.
Why your own baseline matters more than the formula
The most important design choice in any recovery score is what it compares you against. Population averages don't work well for HRV and resting heart rate, because healthy people differ so much. A score that compares you with your own recent weeks is far more useful. A 45 ms night is great news if you usually sit at 35, and a warning if you usually sit at 60.
It also takes a couple of weeks of nights before a baseline is reliable, so any honest recovery score will be a bit tentative at first.
A score you can check
A single number with no explanation is hard to trust. If your score is low, you want to know why: was it the short sleep, the low HRV, or both? A good score shows its working.
Getting one with Lodestar
Lodestar is an iPhone app that turns your Fitbit data into daily Sleep, Recovery, Effort, Stress and Energy scores, each against your own baseline. Tap "What Moved This Score" on any of them to see every input and how much it moved you, and read the Methodology screen for each formula.
- Works with the Fitbit you already wear, through Google Health. No new band.
- Read-only access. Every score is worked out on your iPhone, and nothing is sent to us.
- Core scores are free.