A note before you dive in: This is an invite-only Early Access feature.
Early access features are still being tested and refined. While we continue to improve it, you may occasionally experience bugs or issues. For example, on some days, your band may not capture your overnight data.
You can opt out at any time via the Early Access hub in the Profile tab.
Stability Score (overnight mode) measures two metrics: overnight heart rate (HR) and overnight heart rate variability (HRV), while you sleep wearing your Visible Band 2.0. It uses a four-hour period that starts 30 minutes after you fall asleep. It looks at readings when you are still and ignores times when you are moving. Studies suggest the early hours of sleep are more sensitive to reflect recovery than the whole sleep period.
Why overnight instead of morning?
Overnight measurements are often more consistent because:
They're measured over a longer time period (4 hours vs. 1 minute)
Your body position is more stable during sleep
Sleep provides a controlled environment: consistent posture, mental state and signal quality
Morning measurements require more consistency (same position, same time after waking) which is not always easy
We believe overnight measurements should be more reliable over time for Visible members.
Your overnight HRV may look different from your morning HRV. This is normal. The Stability Score algorithm accounts for these differences when working out how stable your HRV is compared to your recent baseline.