Sleep hygiene can be described as practicing behaviors that improve sleep quality and avoiding behaviors that negatively interfere with sleep qualityRIEDEL, 2000Thus, it includes recommendations for improving sleep quality, such as setting aside time to relax before going to bed, and information about the benefits of a regular sleep routine. In this way, it is possible to evaluate and modify the behavior that leads to a possible sleep complaint. The purpose of this article is to briefly explain the basis for some sleep hygiene recommendations and demonstrate how to assess these behaviors.
Behaviors that make up sleep hygiene include:
1. Do not perform strenuous physical exercise close to bedtime
It is well established in the scientific literature that regular physical exercise improves sleep quality, especially aerobic exercises such as running, swimming, and cyclingPASSOS; POYARES; SANTANA; D’AUREA et al., 2011However, the practice of exercises increases the concentration of cortisol and raises the core temperature, factors that, if performed close to bedtime, can negatively impact the quality of sleep. In addition, most gyms have strong lighting, which also contributes negatively to sleep qualityDIJK; ARCHER, 2009).
2. Avoid naps during the day, especially long naps and naps after 3pm
Napping in the afternoon can negatively impact sleep quality by reducing the homeostatic component of sleep regulation. To learn more, read https://www.condorinst.com.br/como-o-sono-e-regulado/Ideally, the duration of the nap should not exceed 100 minutesOHAYON; WICKWIRE; HIRSHKOWITZ; ALBERT et al., 2017).
3. Have a light snack and avoid drinking too much fluid before bed
This helps to prevent glucose levels from being reduced during the night and, as a result, an awakening to ingest food and/or to use the bathroomCRISPIM; ZIMBERG; DOS REIS; DINIZ et al., 2011).
4. Avoid caffeinated products at least 6 hours before bedtime
Caffeine is a stimulant substance in the central nervous system that acts by preventing the binding of adenosine in the basal forebrain. Thus, it contributes to the maintenance of wakefulness. The half-life of caffeine is 6 hours, which is why it is important to avoid taking it close to bedtime. Preferably, it should be avoided after 3 pmDRAKE; ROEHRS; SHAMBROOM; ROTH, 2013).
5. Avoid drinking alcohol close to bedtime
As much as the general population claims that drinking alcohol contributes to improving sleep quality, science does not support this claim. Excessive alcohol intake before bed impairs sleep architecture, causing nighttime alcohol awakeningsCOLRAIN; NICHOLAS; BAKER, 2014).
6. Avoid nicotine consumption
Nicotine also acts as a stimulant in the central nervous system and for this reason its consumption should already be avoided close to bedtimeSAINT-MLEUX; EGGERMANN; BISETTI; BAYER et al., 2004In addition, smokers often have trouble sleeping when trying to quit.
7. Wear ear plugs to reduce outside noise
Even the lowest noises can contribute negatively to the quality of sleep, so it is important to avoid this condition by using earplugs or adopting white noises, such as the sound of the air conditioning or fan.
8. Avoid sleeping with pets
Animals tend to move around during the night, getting up and down from bed, which can cause unwanted movements and, consequently, nighttime awakenings.
9. Make the environment comfortable for sleep induction
Temperature, lighting, and the type of bed are essential for good quality sleep. The room temperature should ideally be between 20-23ºC and the lighting should be as low as possibleSAINT-MLEUX; EGGERMANN; BISETTI; BAYER et al., 2004).
10. Keeping a regular bedtime and waking up time
Keeping regular schedules promotes better circadian response. This can be achieved through the adoption of alarms in the morning, even during weekends and holidaysCHELLAPPA; MORRIS; SCHEER, 2018).
11. Avoid light exposure for at least 2 hours before going to sleep and increase light exposure right after waking up
Light is the main temporal cue for sleep regulationDIJK; ARCHER, 2009In short, when there is light in the environment, the brain “understands” that it is time to stay awake. Therefore, it is important to let your body know that it is morning as soon as you wake up and, during the night, to let it know that it is ready to go to sleep. If it is not possible to avoid light during this period, use a blue light filter present in smartphonesCHANG; AESCHBACH; DUFFY; CZEISLER, 2015To learn more, read https://www.condorinst.com.br/terapia-de-luz-e-ritmos-biologicos/.
Contraindications for sleep hygiene
- The complete darkness of the bedroom can be harmful to the elderly, who are at risk for episodes of disorientation and/or falls (considering situations in which it is necessary to wake up during the night to go to the bathroom/drink water or other activity).
- The use of earplugs may not be possible for patients who work as caregivers.
- The recommendation to avoid smoking, for chronic smokers, can be more harmful to sleep than the actual act of smoking.
How to assess sleep hygiene
Questionnaires may be used for this purposeSleep Hygiene Index) contains 13 items whose subject must report the frequency of sleep-related behaviors and habitsMASTIN; BRYSON; CORWYN, 2006; TONON; AMANDO; CARISSIMI; FREITAS et al., 2020At the end, a global score is generated, and the higher the score, the worse the sleep hygiene of the person evaluated.Athletes Sleep Behavior Questionnaire)This questionnaire contains 20 specific questions for athletes (such as presence of competitions and night training, frequency of sleeping in different rooms, among others). At the end, a score is generated, and the sleep behavior is classified as good, intermediate or poorDRILLER; MAH; HALSON, 2018; FACUNDO; ALBUQUERQUE; ESTEVES; DRILLER et al., 2021).
Sleep pattern assessment
Actigraphy is a non-invasive technique that can be used to assess sleep pattern and sleep-wake rhythm. The actigraph is a wristwatch-like device that contains light, motion, and temperature sensors. Thus, through this information, it is possible to extract data on variables such as total sleep time, sleep onset latency, time awake after sleep onset, sleep efficiency, time awake and variables related to rhythm, such as cosinor, spectrogram, periodogram, and non-parametric variables such as L5, M10, IS and IV. With this data in hand, it is simple to analyze whether a particular intervention is having an effect.