Sleep: The Missing Link
by Tiago Vasconcelos, RP Research Editor |
Aug 03, 2022
If there’s anything that every person involved in fitness knows, it’s the training, diet and sleep triad. Focusing on these three factors is what will bring you results. Naturally, there are thousands of articles, websites and books on maximizing either your training or nutrition. And rightfully so. But information on sleep is much rarer. This article will give a very broad overview of how to maximize your sleep.
First of all, why does sleep matter? Because sleep deprivation seems to make almost everything worse, and it’s very common in the modern world. So common, that most of us don’t even realize we’re living in a chronic state of sleep debt. Health-wise, it increases your disease risk for almost everything you can think of. It makes dieting worse by making you hungrier, more easily succumb to cravings, and losing more muscle mass. Training wise it makes your performance worse and significantly hinders recovery. It also negatively affects your mood, memory, motivation, and quality of life.
There is no magic number on how many hours of sleep you should get, but the traditional 8h guideline is a good rule of thumb, and larger training volumes likely require more sleep. Everyone’s sleep needs are different, but not by a ton. Many people claim they only need to sleep 6h for instance. But in reality, research has shown that very often they simply have gotten used to that level of energy and they do not notice how affected they are. There are some genes that somehow make people not need as much sleep as the average, but they are very, very rare. If you think you only need 5 or 6h of sleep, then you should be able to get that amount of sleep every day while not having an alarm and waking up naturally while also feeling refreshed in the morning. This is very uncommon.
There is also a normal variation with age, with people reporting needing less sleep as they get older. Although it’s possible that they do need the extra sleep, they just aren’t able to get it since as you age there is a natural calcification of the pineal gland which regulates melatonin. Older people also tend to nap more, which might be a natural response to try to compensate for the sleep gap.
Sleep is regulated by your circadian rhythm, which is your body’s natural clock. While we do have an internal clock, we also depend on external cues to calibrate it. Many people’s circadian rhythm is a complete mess, harming their health, performance and diet, most often because they unknowingly allow external cues to harm it.
The most important thing you can do to avoid messing your circadian rhythm is to have good sleep hygiene. Most crucially, going to bed at the same time and waking up at the same time. While I am going to give several recommendations in this article, if you have to take one thing away from it it is this: have a consistent sleep schedule. It will help you more than you can imagine.
Ideally, the consistent sleep schedule includes the weekends as well. Many people oversleep at the weekends because they are trying to catch up with sleep deprivation during the work week. Catching up is better than nothing, but you still remain with the harmful effects of sleep deprivation. You should try your best to not let that happen. If it’s truly unavoidable, then make the compensation small, for example instead of waking at 7 AM, you wake up at 8 AM. But avoid making an extreme difference, such as from 7 AM to 11 AM.
Using naps is also a good solution. Both during the workweek (although that might prove logistically difficult) and the weekend. This will allow you to recover some lost sleep in a much healthier manner, as naps have been proven beneficial. Ideally, they should be taken after lunch, which is when the body naturally gets sleepier, part of the normal circadian rhythm. Avoid late naps which will make falling asleep more difficult. You should also try to limit naps to 20-30 mins, as longer durations will make you enter deeper stages of sleep which will make waking up difficult and induce lethargy.
Another important feature of good sleep hygiene is a good bedtime ritual. You should try to have a consistent ritual that gets associated with going to sleep. This may include preparing tomorrow’s clothing, taking a shower, brushing your teeth, reading, or journaling. There isn’t a magic recipe, you should try to find something that works well for you. For instance, I find reading to be very beneficial in order to induce a sleepy state, but some do not. Many find that taking a shower helps, while for me it makes me more alert.
I mentioned external cues that calibrate sleep, and the most important one is blue light (although it does a bit into the green zone as well). You might have heard that electronic devices at night are bad for sleep, and this is why. The LEDs produce a significant amount of blue light which disrupts your sleep. It makes your body think that it’s daytime when it’s not, suppressing melatonin production which is needed to fall asleep. Therefore, limiting blue-light is ideal by using blue-light blocking glasses or by using blue-light blocking filters on all your electronic devices. I would try to limit all electronic device usage 2 hours before bedtime.
It’s also worth mentioning that the effect of blue light is sometimes overrated. While it is indeed harmful, generally this light comes in the form of smartphones. However, another factor that is very likely disrupting sleep as well is the mental stimulation from using your phone, and this is completely unrelated to the blue light itself. The true effect of the two factors, light and stimulation, is still being debated and more research is needed to tease them apart, but it’s clear that both are detrimental. Hence the above recommendation of not only avoiding blue light but ideally avoiding all electronics altogether. If possible, try to pick activities that are not stimulating, as discussed in the bedtime ritual.
The problem of electronics has made many people think blue light is harmful to sleep. This is not correct, and in many ways, it is the opposite. Rather, blue light at the wrong time is bad. Blue light is a crucial aspect to regulate your circadian rhythm, as you need it in the morning to fully wake up. Therefore you want to expose yourself to light. Unfortunately, in-door lighting is not sufficient, and to achieve a significant effect you need natural sunlight. One of the best practices you can incorporate is having a morning walk. This way not only do you get sunlight each morning, but also some additional exercise.
Unfortunately, going on a morning walk is not always feasible for everyone. Sometimes there is no time (although very rare, you can usually make time), and sometimes the weather isn’t very conducive to either getting sunlight. The best-case scenario would then be to use a light therapy box, sometimes called SAD light since they help with seasonal affective disorder. While regular in-door lighting is not powerful enough for the effect desired, this box has a much more intense light and is often limited to the blue light spectrum as well. Unfortunately, many of these lights are bad, poorly constructed, and are borderline gimmicks. Nevertheless, getting an ok one is likely better than nothing at all in case you can’t get natural sunlight. Get one with the highest lux possible (generally 10,000), and place it close to you at an angle where the light is coming from slightly above your eyes. Have the light on for 10-20 minutes. A simpler, although not as effective alternative, is to turn on all the lights in your house, as bright as possible, and open all the windows.
Two other factors that often ruin sleep are both caffeine and alcohol. Caffeine keeps you awake, so avoid taking it too late. It’s generally best to avoid taking it after ~6-8h after you wake up, although this is a bit individual and there are genes that regulate caffeine metabolism, affecting how influenced you are by late caffeine. The dose and habituation also play a role. Alcohol is also harmful to sleep. While it may make you fall asleep faster, the quality of sleep is effected in a dose-dependent manner. Ideally, avoid alcohol at night if possible, at least as a frequent occurrence. But if you want a more specific guideline, the body clears around 1 drink of alcohol (1 beer, 1 glass of wine, and 1 shot) per hour. So you can try to plan the timing accordingly.
While exercise is beneficial for sleep, doing it too close to bedtime is harmful, as it induces arousal, making it difficult to fall asleep. Avoid exercising too late in the day, ideally doing it 3-6h before bedtime. If that’s the only schedule where you can fit it in, aim to relax as much as you can as fast as you can after you’re done with training.
If you want some extra boosts for your sleep, you can try having your room pitch dark. However, this often isn’t possible by default with most room setups, light tends to always creep in. There are some blackout curtains available if you want to buy them. An alternative is also using a sleep mask. If you use it and you like them, I recommend getting a good one, I’ve personally used Manta Sleep for many years and it was one of the best things I ever bought. Earplugs might also be helpful if you tend to wake up from outside noise, and you can also have some white noise running in the background, either from your phone or from a white noise machine. If you’re like Dr. Harrison and Michelle Howe, (RP consultants), you can step up the white noise game substantially by using a bluetooth speaker and blasting it on high with whatever consistent noise you find in a white noise app. They use “Ambience” for android. (no affiliation, just sharing!) Lastly, try to have a cool room temperature, somewhere between 16º and 19º. If you don’t have AC, you can turn off the heating, open/close the window, change bed clothing and personal clothing, and have a fan.
There is much more to cover regarding sleep, such as chronotypes, sleep cycles, hormones, sleep disorders, the role of nutrition, beds, dawn simulators, sleep anxiety, sleep supplements, sleep drugs, and more. It's a very complex yet fascinating topic. However, all these more advanced factors are quite meaningless unless the very basics of sleep are covered. By following the advice given in this article, the overwhelming majority of people will never have to worry about anything else.