CBT-i
Jul 29, 2025
Medically Reviewed by
Dr. Elaine Blank, PhD
Sleep restriction might sound like the last thing someone with insomnia needs, but this evidence-based approach is actually one of the most powerful tools for improving sleep quality. Unlike sleep deprivation, which occurs accidentally and disrupts your natural sleep patterns, sleep restriction is a deliberate therapeutic technique that harnesses your body's natural sleep drive to create more efficient, restorative sleep.
Rest, an app based on Cognitive Behavioral Therapy for Insomnia (CBT-I) principles, incorporates sleep restriction as a core component to help users achieve better sleep quality through strategic time management rather than simply spending more time in bed.
What Is Sleep Restriction Therapy and How Does It Work?
Sleep restriction therapy is a behavioral intervention that limits the time you spend in bed to match your actual sleep time [1]. Rather than lying in bed for 9-10 hours hoping to get 6 hours of sleep, you would only allow yourself 6.5 hours in bed initially. This approach strengthens your sleep drive by ensuring you're genuinely sleepy when you go to bed.
The therapy works by increasing sleep pressure throughout the day. When you limit your sleep opportunity, your body produces a stronger drive to sleep, leading to faster sleep onset and deeper, more consolidated sleep [2]. This creates a positive cycle where quality sleep becomes more achievable and sustainable.
Why Does Limiting Time in Bed Actually Improve Sleep Quality?
The counterintuitive nature of sleep restriction lies in its focus on sleep efficiency rather than sleep duration. Sleep efficiency is calculated as the percentage of time you're actually asleep while in bed [1]. A person sleeping 6 hours out of 8 hours in bed has a 75% sleep efficiency, while someone sleeping 6 hours out of 6.5 hours in bed achieves over 90% efficiency.
Research shows that sleep efficiency improvements occur within the first week of implementing sleep restriction [3]. The technique works because it eliminates the frustrating hours of lying awake in bed, which can create negative associations between your bed and wakefulness. Instead, you develop a strong connection between being in bed and actually sleeping. It also strengthens the sleep drive and makes the sleep you get feel more restorative. This teaches you that you are able to sleep well and your anxiety about sleep is often reduced, leading to a greater ease in falling and staying asleep.
How Is Sleep Restriction Different from Sleep Deprivation?
While both involve getting less sleep initially, sleep restriction and sleep deprivation are fundamentally different:
Sleep Restriction:
Deliberate and controlled reduction in time in bed
Maintains consistent sleep and wake times
Focuses on improving sleep efficiency
Temporarily reduces sleep quantity to improve sleep quality
Includes gradual sleep extension as efficiency improves
Sleep Deprivation:
Accidental or forced reduction in sleep time
Often involves irregular sleep schedules
Typically results from external demands or poor sleep habits
Leads to decreased performance and health issues
No systematic approach to recovery
The key difference is that sleep restriction is a therapeutic tool with built-in recovery mechanisms, while sleep deprivation is simply inadequate sleep without a structured plan for improvement.
What Is the 85% Sleep Efficiency Rule?
The 85% benchmark is crucial in sleep restriction therapy [1]. Once your sleep efficiency reaches 85% or higher for a week, you can extend your time in bed by 15 minutes. This gradual expansion continues weekly as long as you maintain good sleep efficiency.
For example, if you start with 6.5 hours in bed and achieve 85% efficiency, you can increase to 6 hours and 45 minutes the following week. This systematic approach ensures that sleep quantity is restored only after sleep quality has been established, preventing a return to inefficient sleep patterns.
Can Sleep Restriction Make Sleep Worse Before It Gets Better?
Yes, sleep restriction sometimes causes temporary sleep loss during the initial weeks of implementation, though many people find that their average sleep loss is quite a bit smaller than they were fearing. [1]. This temporary worsening is expected and necessary for the therapy to work. The initial sleep loss increases your sleep drive, making it easier to fall asleep and stay asleep in subsequent nights.
Most people experience improvements in sleep quality within the first week, even though total sleep time may be reduced, and often feel better rested despite the reduction. The key is maintaining consistency with your prescribed sleep schedule, regardless of how much sleep you actually got the night before. This consistency is what ultimately retrains your sleep system.
Who Should Consider Sleep Restriction Therapy?
Sleep restriction is particularly effective for people who spend excessive time in bed relative to their actual sleep time [2]. Common candidates include those who:
Lie awake for long periods trying to fall asleep
Wake up frequently during the night
Wake up early and can't return to sleep
Spend 8-10 hours in bed but only sleep 5-6 hours
Feel unrefreshed despite spending adequate time in bed
However, sleep restriction should be implemented under guidance, as it requires careful monitoring and adjustment based on individual response patterns.
How Long Does It Take to See Results from Sleep Restriction?
Research indicates that sleep restriction typically produces measurable improvements in sleep efficiency within the first week of implementation [3]. However, the full benefits, including restored sleep duration, usually take 4-8 weeks to achieve.
The timeline depends on several factors:
Initial sleep efficiency levels
Consistency with the prescribed sleep schedule
Individual response to increased sleep pressure
Adherence to other CBT-I components like stimulus control
Studies show that people who maintain their sleep restriction schedule consistently achieve better long-term outcomes than those who frequently deviate from their prescribed bedtimes and wake times [4].
Citations
[1] Edinger JD, Arnedt JT, Bertisch SM, et al. Behavioral and psychological treatments for chronic insomnia disorder in adults: an American Academy of Sleep Medicine clinical practice guideline. J Clin Sleep Med. 2021;17(2):255–262.
[2] Williams, J., Roth, A., Vatthauer, K., & McCrae, C. S. (2013). Cognitive behavioral treatment of insomnia. Chest, 143(2), 554–565.
[3] Muench A, Vargas I, Grandner MA, Ellis JG, Posner D, Bastien CH, Drummond SP, Perlis ML. We know CBT-I works, now what? Fac Rev. 2022 Feb 1;11:4. doi: 10.12703/r/11-4. PMID: 35156100; PMCID: PMC8808745.
[4] Beaulieu-Bonneau et al., "Long-Term Maintenance of Therapeutic Gains Associated With Cognitive-Behavioral Therapy for Insomnia," Sleep (2017)