A Primer on Sleep Restriction Therapy

Disclaimer

I’m not a medical professional and have no medical training. I’m just a guy with insomnia and this is something that helped me out, perhaps it will help you out too.

What is Sleep Restriction Therapy?

Sleep Restriction Therapy (SRT) is a treatment for insomnia developed by Arthur Spielman, PhD. The way I like to think about SRT is that it’s a little bit like a “Couch to 5K” program, only for sleeping. If you not familiar, Couch to 5k is a popular running program and exercise schedule designed to gradually train folks not in the habit of running long distances to slowly build up their stamina and strength until they can regularly run 5KM or longer. SRT similarly tries to train your body to consistently sleep longer and longer amounts through a new customized sleeping schedule. It does this not by reducing the amount of sleep you get, but the amount of time you spend in bed. Also like Couch to 5K programs this is not something that can be accomplished in just a few days. It can take weeks or months to get to where you want to be in terms of how much you’re sleeping, but if you stick with it you should see things slowly improve.

The Limits of Sleep Restriction Therapy

Before we go any further I just want to make sure we’re clear on what SRT can and can’t do. It’s not a magic cure and it may not be right for you. The human body is incredibly complicated and we still really don’t understand sleep all that well. There can be any number of issues and reasons why someone might have trouble sleeping and SRT can’t address all of them. SRT is a program specifically designed to reduce middle of the night awakenings for folks with chronic issues being able to sleep through the night when there doesn’t seem to be any other major factors contributing to this behavior. As always you may want to consult with your medical provider before you take the advice of some guy on the internet.

Sleep Efficiency

The key metric or statistic that SRT cares about is what’s know as your Sleep Efficiency Score. Here’s how it’s calculated:

Sleep Efficiency Score = (Time Asleep / Time in Bed) * 100

Example:

  • You get in bed at midnight.
  • You read and scroll through your phone for 30 minutes before turning out the light.
  • You sleep for 2 hours before waking and having trouble getting back to sleep.
  • You toss and turn for 30 minutes before finally falling back a sleep.
  • You’re up and down fitfully like this the rest of the night, before finally crawling out of bed at 8 am.

Totals:

  • 5 hours actually asleep
  • 8 Hours in bed

Sleep efficiency: (5 ÷ 8) × 100 = 62.5%

This is of course based on just one night. In practice you want to be focused on weekly average sleep efficiency, because we’re more focused on the trend going in the right direction rather than just a single good night. The goal is to get your average sleep efficiency at 85% or higher.

Step 1: Gather data and establish a baseline

The first thing you need to do is gather data on your current sleeping habits for a week or two before you try to change any of them. This can be accomplished by starting a sleep diary. This will be the central place where you track your progress and figure out what kind of changes to your sleep schedule you need to make. You can keep a sleep diary in a number of ways, from a notepad, to a spreadsheet or anything really, as long as you’re consistent with it.

Each diary entry should have the following items:

  • Time you got into bed
  • Time you actually fell asleep
  • How many times you woke in the middle of night
  • How long you were awake in the middle of the night
  • Time of your final awakening
  • Time you actually got out of bed

Personally I recommend the CBT-i smartphone apps. These are free apps developed by the VA Health System that automate a lot of the process of keeping a sleep diary. You still have to manually record each night’s results, but it does a good job of calculating your sleep efficiency from your data and generating charts that make trends easy to spot.

Step 2: Create a new schedule

After you’ve gathered a week or two of results, it’s time to look at your current habits:

Set a Time-in-Bed Schedule:

  • Calculate your average sleep efficiency and your average actual sleep time from the base line data.
  • Based on average sleep time from the baseline data, set a new time-in-bed schedule.
  • For example: if you are averaging only 5 hours of time asleep a night, you should now restrict yourself to only 5 hours of time in bed.
  • This might sound a bit counter-productive, but remember you’re already only getting that much sleep on average, we are not really reducing the amount of time your asleep, we’re reducing the amount of time you’re spending tossing and turning. The goal is to break bad habits and create a positive association between being in bed and being asleep.

Pick a consistent Wake-Up Time:

  • Choose a consistent wake-up time and work backward to determine bedtime.
  • For example: If you need to wake up at 7am, and are only averaging 5 hours of sleep per night, your new bed time is 2am.
  • This may sound a bit extreme and might take some getting use to, but it’s a key part of the program. The goal is to improve your sleep efficiency and then after that we’ll improve your sleep duration.
  • If possible, stick to this wake-up time all week long, even on the weekends. Resist the urge to “make up for a bad night” by sleeping in on Saturday or Sunday. The whole goal of this program is to give your sleep some sorely missing consistency

Step 3: Stick to your schedule

You should now have a “sleep prescription” that you should be following every single night. For example:

  • In bed and lights out at 2am
  • Awake and out of bed at 7am

Stick to the schedule and record your progress in your sleep diary every day. That’s all you have to do for the moment.

If you can’t sleep, get out of bed

  • Even with this new reduced amount of time in bed, you still may find that you can’t always stay asleep the full night. That’s okay, everyone has bad nights sometimes.
  • If you find yourself awake in bed for longer that 15-20 minutes, get out of the bed. Go do something relaxing like reading, or watching something calming on TV for 30ish minutes, then come back to bed and try again.

Step 4: Adjust your schedule

Once a week, review your results and make any appropriate adjustments to your sleep schedule.

What was your average sleep efficiency for the week?

If it was above 80%:

  • It’s time to expand your time in bed by 15-30 minutes.
  • If your sleep schedule was previously in bed at 2am, out of bed at 7am, your new schedule can be in bed at 1:30am, out of bed at 7am
  • When expanding your time in bed it’s usually suggested you update your get in bed time and leave your get out of bed time consistent, but it’s up to you.

If it was below 80%:

  • You may want to think about reducing your time in bed by 15 minutes
  • So instead of in bed at 2am, out of bed at 7am it would be in bed at 2:15am
  • Generally speaking it’s not recommend you reduce your time in bed much below 4 hours

Step 5: Rinse and Repeat

Now that you’ve got your new schedule it’s time to repeat the process:

  • Stick to your schedule for another week, recording your process in your sleep diary
  • Every week, calculate your sleep efficiency and update your schedule based on how well your did

Slowly but surely you will expand how much your sleeping every night. Continue the process until your happy with how much sleep you’re getting. It can be tempting to skip ahead after a few successful nights or weeks, but I promise it’s slow and steady progress that delivers the best results with this process.

Why does this work?

  • Consolidates sleep: By limiting time in bed, SRT helps consolidate sleep into a more continuous and efficient period, reducing fragmented sleep patterns.
  • Realigns circadian rhythm: It helps reset the body’s internal clock by creating a consistent sleep schedule.
  • Breaks negative associations: It helps break the cycle of associating the bed with wakefulness and anxiety about sleep.
  • Increases sleep drive: Restricting time in bed builds up sleep pressure, making it easier to fall asleep and stay asleep.

Basic Sleep Hygiene

Here are some general tips to improving your sleep, regardless of whether your doing SRT or not. No judgments on any of these ideas, this is just the habits that most sleep experts recommend for a better night sleep, especially for someone on a SRT program.

  • Don’t nap during the day
  • Cut out or at least severely reduce caffeine from your diet
  • Use your bed only for sleep. Don’t read or look at screens or do anything else in your bed, just sleep.
  • Avoid bright lights before bed, especially blue lights (like most screens)

Trust The Process

I know all of this probably sounds like a lot, and I was certainly pretty skeptical when I first tried the program, but it really helped me. Anxiety can be one of the strongest sources of insomnia, and as you struggle with insomnia, that anxiety can compound in a vicious cycle. Personally it was really helpful and calming to know that I had a system in place that was going to improve my sleep. Even if I had a bad night, I didn’t need to worry about it, all I had to do was trust the process.