About Sleep Debt

What is "Sleep Debt"?

If your daily healthy sleep time requirement is 7 hours but you don't reach it, a sleep time deficit is created, which is called "sleep debt." For example: If you need 7 hours of sleep but only get 5 hours, you accumulate 2 hours of sleep debt. If this continues for 5 days, you'll accumulate 10 hours of sleep debt.

Accumulating sleep debt can lead to fatigue, anxiety, and difficulty concentrating.

However, occasional sleep deprivation is not a big problem by itself; it's the chronic, long-term lack of sleep that can have serious consequences.

How to Repay Sleep Debt?

First, aim to get the full amount of sleep needed each night; then, you can catch up on the sleep debt by sleeping extra when needed.

Here are some sleep tips to help you get enough sleep and pay off your sleep debt sooner:

  • Sleep when you feel tired—don't force your body to stay awake;
  • Keep a regular sleep schedule, avoid staying up late;
  • Maintain a consistent exercise routine to improve sleep quality;
  • Turn off your phone before bed, keep a calm mind to help your brain enter sleep more quickly.

How Does PeakWatch Define Sleep Debt?

PeakWatch defines sleep debt by measuring the difference between the user's actual sleep time and their target sleep time. Specifically, sleep debt reflects the cumulative sleep deficiency over a set period (typically 7 or 14 days). When your actual sleep time is less than the recommended target, this deficit adds up to sleep debt. PeakWatch calculates sleep debt over a 14-day cycle.

For example, if your target sleep time is 8 hours per night but you only sleep for 6 hours on a given day, that day's sleep debt is 2 hours. As time goes on, if sleep deprivation continues, the sleep debt will grow and could negatively impact recovery and overall health. PeakWatch tracks your sleep debt to help you understand your sleep deficiency and provides recommendations to improve your sleep habits for better recovery.

How to Customize Target Sleep Duration?

In PeakWatch, you can set a personalized target sleep duration under "Settings" → "Sleep" → "Sleep Duration" to account for individual differences.