Readiness score (Oura), Recovery score (WHOOP), and Body Battery (Garmin) all answer the same fundamental question: how well did your body recover overnight? Unlike a raw sleep score, readiness reflects a multi-day picture of your physiological state. Here's what's behind it and how to improve it.
What Readiness Actually Measures
Readiness scores are designed to measure preparedness for physical and cognitive load — not just whether you slept. The inputs vary by device:
Oura Readiness Score (0–100):
- Previous night's sleep score (most weighted)
- HRV balance (your overnight HRV vs. your personal 30-day baseline)
- Resting heart rate (vs. your baseline)
- Body temperature deviation (from your baseline; fever or illness shows up here)
- Recovery index (how quickly your heart rate recovered during sleep)
- Sleep history (how you've slept over the past 2 weeks, not just last night)
- Activity balance (whether you've been too sedentary or too active recently)
WHOOP Recovery Score (0–100%):
- HRV (most heavily weighted)
- Resting heart rate
- Sleep performance (% of sleep need met)
- Respiratory rate
Garmin Body Battery (0–100):
- Overnight HRV stress
- Sleep quality and duration
- Daytime activity and stress depletion
- Heart rate metrics
The critical insight: readiness is not just about last night. HRV balance (Oura) and WHOOP HRV are compared against your recent history. One great night won't save a readiness score that's been suppressed by a week of poor recovery.
Why Readiness Scores Drop
Alcohol (Most Common)
Alcohol suppresses HRV, elevates resting heart rate, and fragments sleep — hitting readiness through every major channel simultaneously. One night of drinking can drop an Oura readiness from 80 to 55. Repeated drinking across a week produces chronically suppressed HRV balance.
Sleep Debt
If you've been sleeping 6 hours per night for three nights, your readiness score will reflect that accumulated deficit — even if you sleep 8 hours on night four. Sleep debt is a real physiological state that takes multiple good nights to resolve.
Overtraining
High training load without adequate recovery keeps resting heart rate elevated and HRV suppressed. WHOOP specifically tracks daily strain and factors it into whether your sleep adequately recovered you. An athlete who trains hard every day without rest days will see chronically low recovery scores.
Illness
Body temperature deviation (Oura) and HRV suppression both respond to illness before symptoms appear. A readiness score that suddenly drops with no obvious behavioral explanation often precedes illness by 1–2 days.
High Psychological Stress
Chronic stress keeps cortisol elevated, which keeps the sympathetic nervous system activated, which suppresses HRV — the primary readiness input for Oura and WHOOP.
How to Improve Readiness Consistently
Priority 1: Sleep Duration
Nothing produces readiness gains faster than simply sleeping more. Go to bed 30 minutes earlier. The HRV, RHR, and recovery index improvements from adequate sleep show up within 3–5 days.
Priority 2: Eliminate Alcohol
The most dramatic short-term intervention. Most people who track readiness and stop drinking for two weeks see their scores increase by 15–25 points on average. The HRV rebound from alcohol elimination is usually visible within 3–4 days.
Priority 3: Consistent Schedule
HRV balance (used heavily by Oura) requires a stable baseline to compare against. An irregular schedule disrupts that baseline and keeps HRV from reaching its natural ceiling. Going to bed and waking at the same time every day — including weekends — is the most reliable way to stabilize HRV balance.
Priority 4: Exercise Balance
Exercise improves readiness long-term but can temporarily suppress it after hard sessions. The pattern: low readiness the day after a hard workout, higher readiness after a recovery day. If you see chronically low readiness despite sleeping well, check whether your training load exceeds your recovery capacity. Add a rest day or easy day.
Priority 5: Stress Management
Consistently high overnight HRV stress (Garmin) or low HRV balance (Oura) that isn't explained by alcohol or training is usually psychological stress. Structured wind-down, paced breathing before bed, and longer-term stress reduction practices (regular exercise, social connection) improve this over weeks.
How to Use Your Readiness Score
Oura and WHOOP both give daily activity and training recommendations based on readiness. Green (high readiness) = go hard. Yellow = moderate. Red = rest.
Using these recommendations reduces overtraining risk and improves long-term performance and sleep quality simultaneously. The athletes who see the best readiness scores over time are those who respect low-readiness signals rather than pushing through them.
Track your readiness alongside your habits in SleepBetter.ai — log what you did yesterday, how you slept, and see the pattern that explains your score. Free on iOS.