How much sleep do I need?
This is the age-old question. I’m sure most of you reading this would have heard somewhere that you need 8hrs of sleep, or if we were to believe Arnold Schwarzenegger, we only need 6hrs of sleep and should just sleep faster as he recommends. However, most recommendations for sleep will range from 7-9 hours sleep per night. While many people will claim to function perfectly fine on less then this the research couldn’t be clearer for the need to have at least 7 hours sleep each night. There have been studies conducted where the same duration of sleep between 7-9 hours was maintained, but the timing of it was shifted. Instead of going to bed at say 9pm, subjects were going to sleep at 11pm or 12am instead.
The reality is, what we may recognise as our typical sleep pattern of sleeping late or sleeping less then 7 hours per night, these things are classified as being sleep deprived in the research. Sleep deprivation brings with it a bunch of potential negatives, particularly when it’s compounded over an extended period of time. In the brain there is a significant decrease in coordination, motor skills, memory, attention, decision making and a loss of inhibitions and even changes in personality. Metabolically there are also significant decreases in the body’s ability to tolerate glucose. (carbohydrates) Some studies show that with only one night of impaired sleep can give you the similar blood sugar management of a type II diabetic.
In terms of muscle performance & strength, as you could imagine there is a decrease in strength, power output, force production and aerobic endurance. Not to mention the decrease in motor skills and coordination that have already been mentioned.
From a practical results point of view, being sleep deprived really works against you. Not only will your ability to train effectively decrease, but your recovery will also be impaired, your body’s ability to take in nutrients will be impaired, your subconscious activity levels may decrease and your decision-making ability around food, motivation and consistency may also be affected, making it that much harder to achieve your goals. Even if you stick to your diet and training routines long term, research does show that in weight loss studies while subjects who are sleep deprived vs not sleep deprived will still lose similar amounts of weight, there is a higher % of fat free mass (muscle, bone etc.) being lost in sleep deprived subjects. Whilst those who sleep an optimal amount lose a greater amount of fat mass.
If you care about your physique and body composition goals, as well as your overall health and well-being, sleep is extremely important and we should be doing everything possible to improve and maintain sleep quality.
How to improve sleep?
There are endless ways and options to consider when it comes to improving sleep. To help you understand things better we can categorise strategies into environmental, lifestyle and nutritional factors.
Environmental
Environmental factors refer to things in your own environment that might be causing disrupted sleep at night. Light and noise are the two most obvious, even the faintest amount of light from a television on standby or radio clock is enough to disrupt sleep quality. The ideal situation is to have your room dark enough so that you can’t see your own hand in front of you. If this is not possible due to where you live, then the use of a sleeping mask is a good option here.
Noise is similar, whilst you might not even be waking up from noise during the night it can be enough to disturb your sympathetic brain regions throughout your sleep, and get in the way of you being able to fall into deeper stages of sleep. An obvious solution is to wear ear plugs, or you might want to consider having some kind of white noise like a fan or even white noise machine, to drown out all inconsistent noises and give your brain a constant sound to focus on.
Temperature is an important factor, as your body needs to decrease its core temperature to be able to fall asleep. The ideal room temperature for this to happen is roughly 16-18 degrees Celsius. One of the less talked about environmental factors is humidity and dryness in the air. If you are someone who uses a lot of air conditioning, heating or if it’s just particularly dry in the air where you live. All these things can dry out your sinuses and create inflammation in these structures called the turbinates. Once inflamed these can block your nasal passageways and make it difficult to breath through your nose, as a result this can cause you to snore and have disruptive sleep. A solution is to use a humidifier at night in your bedroom to keep the humidity at roughly 50-70%.
Lastly the bedding that you use is of vital importance to ensure that your airways are aligned to allow for proper breathing when you sleep. This will depend not only on comfort but also your body shape and size, and whether you sleep more on your side or your back. Generally speaking, you want to avoid having your neck compressed or bent, that should give you some idea as to what kind of mattress and pillow combination is best for you.
Lifestyle
Lifestyle factors can become a very long list, for arguments sake we’ll focus on the obvious around timing exercise, light exposure and general routines. One of the best things you can do for your sleep at night is to ensure you get at least 10min of light exposure when you wake up in the morning. Ideally this would be outdoors and come from natural light because that’s the brightest. However, depending on where you live in the world and what time you wake up, you might have to rely on artificial light. This exposure helps us set off the suprachiasmatic nucleus and all of your body’s internal circadian rhythms. In a similar way some light exercise like a light walk first thing in the morning and in the evening, are also useful ways to promote better quality sleep.
In regards to more intense exercise you want to try to keep this away from the last few hours before bed, as this has been shown to disrupt your ability to fall asleep, especially if stimulants are involved. The body thrives off routine, try to avoid sleeping in on days off to “catch up on sleep” as this can lead to more of a jetlag feeling and make it difficult for your body to align itself into a proper routine with sleep wake cycles. Having a consistent bedtime is a good idea along the same lines of this as well.
Nutritional Factors
Nutritionally there are a lot of different strategies out there that people swear by such as having carbs before bed or a spoon of honey or milk or nothing at all. From a circadian perspective digestion usually slows down in the evening and throughout the night. You probably want to avoid having anything heavy right before bed as it will be difficult for your body to digest that food and will disrupt your sleep. As a rough guide try to avoid eating anything large 2-4hrs before bed. If you are someone who struggles with sleep, It is recommended trying this. It doesn’t mean that you eat less or change what you eat, but simply shifting it forwards slightly can make a big difference to your overall sleep quality.
Lastly you want to avoid using stimulants if possible, the half-life of caffeine is between 4-6hrs. What this means is if you have an espresso shot or pre-workout containing 100mg of caffeine at 7am. 4-6 hours later at 11am-1pm you would still have 50mg of caffeine in your bloodstream. Then 4-6hrs later after that you would still have 25mg in your bloodstream. Which is enough to disturb sleep onset and sleep quality. This is from just one dose at 8am, if you are having several doses or larger doses and having it later in the day the effects will be magnified. The less you can rely on stimulants to get you through the day the better.
References
- Ganbaru Method, Eugene Teo, Published November 2021, Accessed November 13th Introduction (ganbarumethod.com)
