Regardless of how you slept the night before, some days, you can just take a quick nap to reenergize and get the most out of your day. However, the length of your nap can determine how you feel when waking up from your nap and how quickly you fall asleep at night. A perfectly timed nap won’t leave you feeling groggy and unfocused or disrupt your natural sleep-wake cycle.
In this article, we outline what science has to say about the best nap length.
What Is a Sleep Cycle?
To better understand the effects of napping, it is important first to understand the stages of sleep and how they work together to create one full sleep cycle.
One sleep cycle lasts about 90 to 120 minutes. If you sleep between 7 to 8 hours a night, you experience 4 to 5 cycles.
In stage 1, also known as “light sleep,” brain wave activity slows, and muscle tension decreases. This stage lasts about 5 to 20 minutes. In stage 2, the heart rate and core body temperature drop, brain activity continue to slow, and we become less aware of environmental stimuli. Stage 2 lasts for about 30 to 60 minutes.
During stage 3, also known as “deep sleep” or “slow-wave sleep,” delta waves work to clean out the brain and consolidate memory. HGH (human growth hormone) repairs and rebuilds muscle tissue. This stage lasts between 20 and 40 minutes.
Next, REM sleep begins. During REM, the body becomes immobile, brain activity increases, and the eyes begin a quick side-to-side motion known as rapid eye movement. This stage only lasts about 10 minutes, but it gradually lengthens throughout the night.
It is also important to note that sleep stages are not linear. REM sleep can begin at any time in the sleep cycle, and we may not always start each cycle at stage 1. Additionally, we may not move from stage 3 to REM automatically, but, instead, go back to stage 2 or 3 before entering REM.
However, in most cases, REM sleep starts about 90 minutes after falling asleep. We typically start each cycle in stage 1 or 2 and move through to stage 3, with intermittent periods of REM sleep taking place throughout. However, because REM sleep lengths each time, the longer you sleep, the more REM sleep you experience.
Different Nap Lengths
Now that you understand the ins and outs of the sleep stages, let’s look at how they work during a nap.
The Power Nap: 10 to 20-Minute Napshow that 10 to 20 minutes is the perfect nap length, often referred to as a “power nap.” Sleeping for no more than 20 minutes means that you will likely stay in the 1st stage of sleep, light sleep, and you will still be somewhat aware of your surroundings as you nap. Therefore, you will wake up feeling refreshed but not groggy.
The Groggy Nap: 30-Minute Nap
If you nap for longer than 20 to 30 minutes, you will likely enter stage 2 of sleep. During stage 2, K-complexes (large brain waves) reduce the effects of environmental stimuli on the brain, helping us become detached from our environment so we can slip into the deeper stages of sleep.
If you wake up from a nap in the middle of stage 2, you may experience what experts refer to as “sleep inertia.” This is defined as a period of extreme mental and physical grogginess, lethargy, and disorientation.
The Longer Nap: 60-Minute Nap
During a 60-minute nap, you will spend some time in stage 3 (deep sleep). Stage 3 sleep is incredibly beneficial. Memories and impressions are consolidated during this stage, and pertinent information is moved to the neocortex, the brain’s long-term memory storage.
However, waking during stage 3 will have similar effects as waking from stage 2. You may experience sleep inertia and feel groggy for a period of time after waking.
The REM Nap: 90 to 120-Minute Nap
Napping for 90 to 120 minutes means you will get some REM sleep and potentially experience a full cycle of sleep. With a long nap, you will get all of the sleep cycle benefits without the risk of sleep inertia or grogginess when waking. If you are suffering from sleep deprivation and need to take a daytime nap, it is best to opt for a 90 to 120-minute nap if possible.
Although a longer nap can help you reenergize, it may interfere with your ability to fall asleep quickly at night. Therefore, if you notice that a long nap results in poor quality sleep at night, it is best to opt for a shorter nap between 10 to 20 minutes long. It is also best to take longer naps before 3 p.m.
Frequently Asked Questions
Why am I more tired after a nap?
If you feel tired after a nap, it is likely because you woke up from your nap during stage 2 or stage 3 of sleep. A 10 to 20-minute nap will ensure that you wake up in the lightest stage of sleep, stage 1, and wake up feeling refreshed. If you need a longer nap, try to sleep for at least 90 minutes. This length of time will allow you to get some REM sleep and wake up without feeling disoriented and overly exhausted.
Are naps good for your heart?
Evidence suggests a daytime nap once or twice a week could lower your risk of heart attack, stroke, or heart failure by as much as 48 percent. One study followed participants between the ages of 35 and 75 for 5 years. They found that, even though nap length varied, those who reported napping once to two times a week had a lower risk of heart disease than those who didn’t nap.
What is the best nap length when you are sick?
When you are sick, your body is working to heal itself. Therefore, it is best to nap as much as possible and not worry about limiting your sleep time.
What is the best time of day to nap?
To avoid disturbing your nightly sleep schedule, most sleep experts recommend napping before 3 p.m. Naps later than this could make it difficult for you to relax and get to sleep on time.
Why do I need to nap every afternoon?
If you frequently feel the need for an afternoon nap, it may be because you are not getting enough sleep at night. However, for healthy adults, daytime napping offers many benefits. Naps can help reduce fatigue, promote relaxation, improve mood, and increase focus.
Adequate sleep is vital for your overall health and wellbeing. If you cannot get proper sleep during the night or find yourself overly tired during the day, an afternoon nap could help you feel your best.