Even when people who usually sleep for short periods extend their time in bed by 2 hours every day, their actual sleep does not increase by 2 hours. In a 2026 study, actual sleep among 30 healthy young adults increased by an average of about 47 minutes according to wrist-based measurements, while subjective sleepiness and sleep quality improved.[1]
The number may seem small, but the key point is that this was not a failure. Sleep does not fill in like an empty space on a calendar. The opportunity to sleep needs to be expanded gradually, and we need to consider not only “what time did you go to bed?” but also “how long did you actually sleep, and how did you feel during the day?”
How was the 30-person sleep extension study conducted?
The participants were 30 healthy adults with an average age of 23.1, whose usual nighttime sleep was under 6 hours 30 minutes. After measuring their usual sleep for 2 weeks, the researchers asked them to increase the amount of time they spent in bed by 2 hours every day for 4 weeks. It was a small study comparing the same people before and after the intervention, without a randomized control group.[1]
Baseline sleep averaged 5.5 hours. During the intervention, time in bed increased by about 61 minutes on average, while actual sleep measured by a wrist activity monitor increased by about 47 minutes. A home electroencephalography device recorded an increase in actual sleep of about 62 minutes. Bedtime became earlier by about 52 minutes on average, but sleep regularity did not improve significantly.[1]
Why did 2 extra hours in bed result in only 47 more minutes of sleep?
There is a gap between the time you get into bed and the time your brain falls asleep. When the schedule is moved earlier, it may initially take longer to fall asleep, increasing the amount of time spent awake. In the study, total sleep time increased, but sleep efficiency did not improve noticeably, and time awake during the night increased slightly.[1]
So it is difficult to conclude that you got enough sleep based only on a record showing that you spent 8 hours in bed. Conversely, a 47-minute increase is not a small change. If someone who slept 5 hours 30 minutes every weekday increases that to 6 hours 17 minutes, it could be a starting point for reducing daytime sleepiness. However, because the participants were young and healthy, the same figures cannot be applied to shift workers, older adults, or people with chronic insomnia.
In everyday life, how many minutes at a time is realistic?
Rather than moving bedtime 2 hours earlier all at once, create 30 minutes of additional sleep opportunity during the first week. Keep your wake-up time the same and begin your bedtime routine 30 minutes earlier. For 7 days, record four lines: your actual bedtime, estimated time of falling asleep, wake-up time, and daytime sleepiness.
In the second week, add another 15–30 minutes if actual sleep has increased and your morning functioning has improved. If you are only spending more time in bed and it continues to take more than 30 minutes to fall asleep, stop trying to go to bed earlier. Spending long periods awake in bed can reinforce insomnia and may require a different approach.
What two things should you look at before aiming for 7 hours?
The US Centers for Disease Control and Prevention recommends that adults aged 18–60 get at least 7 hours of sleep per day.[2] In a 2024 US survey, 30.5% of adults slept fewer than 7 hours on average.[3] But 7 hours is a population-level recommendation, not a finish line. Even with the same 7 hours, frequent awakenings or daytime sleepiness mean sleep quality and the possibility of a health condition should be considered separately.
The first measure is consistency in wake-up time. The second is daytime functioning. Look at whether you hit the snooze button repeatedly, feel sleepy during morning meetings, or compensate by sleeping more than 3 hours later on weekends. In the study, sleep regularity did not automatically improve even when sleep duration increased.[1]
Who may not be suited to going to bed earlier?
If you become more tense after getting into bed, have difficulty falling asleep at least 3 nights a week for more than 3 months, or experience snoring and pauses in breathing, uncomfortable legs, or sleepiness while driving, do not simply keep repeating sleep extension. Conditions such as insomnia, sleep apnea, and restless legs syndrome may require evaluation and different treatment.
FAQ | Does sleeping two extra hours on weekends have the same effect?
This study involved increasing sleep opportunity every day for 4 weeks, so it was not the same as catching up on sleep at the weekend. Although weekend recovery sleep may reduce fatigue, it cannot be assumed to fully offset both weekday sleep deprivation and a large shift in schedule.
FAQ | Is it enough to look only at my sleep app score?
Look at trends in the raw data rather than the score. Check whether bedtime and wake-up time, estimated total sleep, and daytime sleepiness improve in the same direction over 2–4 weeks. Consumer devices do not replace medical sleep testing.
How to design 30 minutes for tonight
Set your bedtime alarm 30 minutes earlier, dim the lights and turn off screens from that time onward. Keep your wake-up time fixed. In the morning, write one line about whether you feel less sleepy rather than simply whether you slept more. If actual sleep and daytime functioning have both improved after 2 weeks, add the next 15 minutes then. Sleep extension is not about forcing a number to be filled; it is a process of widening the margin your body can accept.
