The Importance of Sleep for Learning, Body Composition, and Strength

Essentially a good training regime boils down to 3 things. Training, Nutrition and Recovery.

When it comes to a fitness overhaul most people start with the training element. We feel strongly that when it comes to training everybody should be basing their program around strength, which we provide a rationale for here. Find a knowledgeable trainer who tailors the training program to your specific needs, work hard, fit in some high intensity intervals and you’re on the right path.

Of equal importance is nutrition. There are many studies that show that when it comes to improving body composition and performance, exercise alone just doesn’t cut it. It has to go hand in hand with a well constructed eating plan for significant results. That’s why we invested a huge amount of time in developing our Primal Guide to Eating. We are currently working on edition 2 of the book which will contain a far more detailed recipe section. The book goes out free of charge to all of our members. 

But recovery is a critical piece of the pie that is often glossed over. After all, our training is only as good as our recovery from and adaptation to each session. There are several options for recovery - some are more practical than others but may include:

  • good sleeping patterns / extra sleep / 20 minute power naps etc
  • massage / self massage
  • hydrotherapy (hot / cold / deep water immersion)
  • light aerobic type work (walking / light running / cycling etc)
  • stretching / mobility work

For us sleep is the foundation of recovery. If you are not sleeping for the correct amount of time in an uninterrupted fashion then forget about all of the other recovery strategies. They are the nice to haves but sleep is the must have!


In order to understand just how important sleep is we need to understand what happens when we go to sleep. According to Dr. James Maas, author of power sleep and professor of psychology at Cornell University, sleep can be broken down into 5 distinct stages.

Stage 1 - Drowsiness (Duration 10 seconds to 10 minutes).

The transition from being awake to falling asleep characterized by shallow irregular breathing. During this stage you respond quickly to disturbances since you’re still aware of your surroundings.

Stage 2 - Light Sleep (Duration 20 minutes approx.)

Heart rate begins to slow, eye movements stop, blood pressure drops, muscles relax to a greater extent. You are no longer aware of your environment.

Stages 3 & 4 - Deep Sleep (Duration 50 minutes approx.) 

Stage 3 represents a transition from light sleep into stage 4 deep sleep. During these stages your body begins to regenerate and repair from the days stressors. For example it is during stages 3 & 4 that human growth hormone is released to repair and regenerate muscle tissue. The immune system is also given a boost and energy stores are restocked during this time. If you are woken during deep sleep it will take you around 15-20 seconds to fully wake up. 

Stage 5 - Rapid Eye Movement (REM) (Duration begins at 9 minutes but doubles each time REM stage is entered)

REM gets most of the publicity when it comes to sleep stages. This is the sleep stage that is critical for learning because information gathered during the day is transferred from the short-term memory region of the brain into long term memories. For example if you take a tennis lesson and learn a new skill it will only be consolidated into a long-term “muscle memory” if you experience adequate periods of REM through that nights sleep. 


It’s important to note that a sleep cycle does not go through stages 1-5 consecutively. After passing into light sleep (stage 1 to stage 2) the cycle progresses into stage 3 and then stage 4. After stage 4 sleep returns into stage 3 and then stage 2 before entering into a period of REM. This means that we enter a period of REM approximately every 90 minutes. The first period of REM is short, lasting only around 9 minutes before sleep goes through another 90 minute cycle. However every time we enter into a period of REM its duration doubles, up to a maximum of around 60 minutes, which we only experience if we are able to sleep for 4-5 cycles uninterrupted. For most people this means getting 8 - 9.25 hours of continuous sleep per night. Any less than this and we miss the later and longer periods of REM. This obviously has profound implications on our learning. For example if we manage 8 hours of sleep a night we can expect around 4 periods of REM totaling 130 minutes. 9.25 hours would buy you 5 periods of REM totaling almost 200 minutes. But if you only manage 6 hours, which is common for many of us you will only be exposed to 2 periods totaling 70 minutes of REM.

Also of importance is the fact that certain processes only occur after several hours of continuous sleep. For example only after around 6-8 hours do “sleep spindles” occur. These are calcium cascades (which are impossible to replicate with supplementation) in the brain that help to consolidate the step-by-step athletic motor sequences into automatic, fluid and fast movements. This is thought to be so important to future athletic performance that some NFL players have been required to sleep under controlled conditions if they have had an outstanding game in order to make similar performances in the future more likely to happen. Just what you want after the game of your life!


Similarly though the more we can cycle into the restoration stages (3 and 4) the more the body produces human growth hormone and the more we are able to repair, restore and increase lean, metabolically active muscle mass. On the other hand if we deprive ourselves of even 1 hour of sleep per night there is an effect on the activity of the hypothalamus resulting in higher levels of the stress hormone cortisol, which in short has been shown to increase appetite, cause oxidative stress, promote fat storage and blunt the effects of resistance training. Similarly testosterone production, which is critical for growth and repair is also blunted with a lack of sleep.

The hormone grehlin is released in higher concentrations when sleep deprived, which is known to increase a persons appetite and promote overeating. Similarly the hormone leptin, which promotes satiety after eating is suppressed. And it’s not just a loose relationship. In fact a joint project between Stanford and the University of Wisconsin, which studied about 1000 subjects, investigated the effects of sleep on circulating grehlin and leptin as well as body-fat percentage. It was found that those who slept less than 8 hours per night had higher circulating grehlin, lower circulating leptin and had higher body fat percentage. What’s more there was a strong trend towards the heaviest subjects in the study being the ones who slept the least and vice-versa. 

Another negative effect is that a lack of sleep has been shown to affect the bodies ability to metabolise glucose resulting in insulin resistance, and fat gain. The immune system is also impaired by a lack of sleep and a chronic lack of sleep has been shown to bring about changes in heart rate variability and blood pressure and can lead to inflammation. A vicious cycle can then begin because a pro-inflammatory state can cause hormone imbalance, the effect of which is often difficulty sleeping!


Here are a list of tips and tricks to try, which will hopefully get you off to the land of nod and keep you there for that target 8-9.25 hours sleep.

Limit Caffeine and Alcohol Consumption Before Bedtime 

Caffeine is considered to have a stimulating effect for up to 9 hours post consumption. Work out your target sleep time and work backwards from there to calculate when you should have your last cup. For most people having your last cup around lunch wont affect your sleep. While alcohol may seem to help you fall asleep, studies have shown that the quality of that sleep is badly affected and most people wake up several times through the night with restlessness and dry mouth.


Watching tv, playing on the ipad, iphone, etc is known to have a stimulating effect, which delays the process of falling asleep. Aim to switch off all electrical goods at least 30 minutes before lights out. There is also some research that suggests that electrical fields from appliances can negatively affect sleep - even when they are switched off at the appliance. Juries out on this one but it may be worth switching off major appliances at the wall all the same. 

Perform a Brain Dump

This is one of the best tips around and genuinely works. Always have a paper pad and pencil by your bed. Every night before lights out write down everything you need to do the next day or things that need your attention. Often people can’t sleep because little issues or ‘to-do’s’ pop into their head. Generally if you can get them down on paper you can stop thinking about them. Some people also like to write down a few good things about the day passed like people they may have helped or things they are looking forward to the next day so that they go to sleep having looked at the world in a positive way. 

Get a Sleep Routine 

This can sometimes be difficult to do and requires a bit of discipline but try and go to sleep at the same time and get up at the same time every day. If you can achieve this your body will get used to winding down for sleep at the same time daily. Through the week this is often easily manageable but then Friday night rolls around...if you can make it work without losing friends then give it a go.


This is another top tip that really (really) works. If you can make the bedroom a place where you go to sleep and nothing else then sleep will come much much easier. Some even suggest renaming the bedroom the 'sleep room' to encourage people consider that to be the sole purpose of the room. Get rid of the TV in the bedroom and make your room as dark as you possibly can (any new parent will back us up with the positive effects this has on juniors sleep). Get rid of LED alarm clocks, get heavy black out blinds, get the room at the right temperature and even consider a towel for under the door to block out light completely. If you wake up in the middle of the night and you need twenty seconds or so for your eyes to adjust to the darkness, then you have yourself a bat cave!

Shower and Stretch

After you have had your evening shower consider performing a round of simple static stretches as part of your routine. This helps to alleviate any pent up muscular tension and also has a calming effect on the nervous system. We're not talking about a yoga session here - keep it simple and non-taxing, holding each stretch for around 15-30 seconds each time.

Take a Daily Multi-Vitamin

A recent study in Nutrition Journal found that over 8 weeks, young adults of average weight who took a multivitamin had much better mood, mental acuity, energy levels, and sleep than a placebo group. Interestingly the beneficial effect on energy levels and more restful sleep was particularly evident in the female participants. Although not statistically significant, a few participants also reported a decrease in appetite. Better sleep and more energy during the day to work-out is a winning combination but never consider a multi-vitamin to be a magic bullet against a poor diet. Sort your diet first then support it with a multi-vitamin. 

Consider Adding Some White Noise

This one seems to work wonders for some people and have little effect on others. White noise is that indescribable sound that you might use to mask other sounds e.g the hum of a washing machine or fan. Nowadays you can download white noise apps for your smart phone. I tried this and it didn’t appear to do anything whereas others can’t live without it. Try it and see and let us know what you think. 

And Finally

Studies have shown that in 1910 people were getting an average of 9 hours sleep per night. Nowadays that figure is considered to be closer to 7. If you are interested in trying to quantify how well you are sleeping then have a look at the sleep cycle app for smartphones. It’s an alarm clock app that not only gives you feedback on how well you slept through the night (by using the accelerometer built into your phone to clock how much you moved through the night) but also claims to wake you up during the last light sleep period before you need to get up, which is claimed to prevent that ‘getting out of bed on the wrong side’ feeling. Again worth a try.

Anyway hopefully you haven’t stayed up late to read this saga of an article, but we really feel it’s an important message to convey. If you have any strategies of your own that have worked for you then please share them on our website comments section or on our facebook page.

Sleep well!



Dettoni, J., Marciano, F., et al. Cardiovascular Effects of {partial Sleep Deprivation in Healthy Volunteers. Journal of Applied Physiology. 2012.

Taheri S, Lin L, Austin D, Young T, Mignot E (2004) Short Sleep Duration Is Associated with Reduced Leptin, Elevated Ghrelin, and Increased Body Mass Index. PLoS Med 1(3): e62. doi:10.1371/journal.pmed.0010062

Yi, s., Nakagawa, T., et al. Short Sleep Duration in Association with CT-Scanned Abdominal Fat areas: The Hitachi Health Study. International Journal of Obesity . February 2012. 

Kobayashi, D., Takahashi, O., et al. High Sleep Duration Variability is an Independent Risk Factor For Weight Gain. Sleep Breath. February 2012.

Sarris, J., et al. Participant Experiences From Chronic Administration of a Multivitamin Versus Placebo on Subjective Health and Wellbeing. Nutrition Journal. 2012


4 comments (Add your own)

1. wrote:
Hello friends, its great post regarding teachingand fully explained, keep it
up all the time.

Fri, May 19, 2017 @ 5:33 PM

2. wrote:
I'm so happy to read this. This is the kind of manual that needs to be given and not the accidental misinformation that is at
the other blogs. Appreciate your sharing this greatest doc.

Sun, July 2, 2017 @ 11:45 PM

3. wrote:
Incredible quest there. What occurred after? Good

Mon, July 3, 2017 @ 12:52 AM

4. wrote:
I go to see everyday some sites and websites to read articles, except this
blog offers quality based content.

Sat, January 6, 2018 @ 3:05 AM

Add a New Comment


Comment Guidelines: No HTML is allowed. Off-topic or inappropriate comments will be edited or deleted. Thanks.