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Takeaways for Sleep Recommendations
- You should probably sleep more. Sleeping more is associated with a wide range of benefits, of which quite a few pertain to your ability to get results and live a good life.
- Try sleeping more. This is dependent on your age and how much you train, but try sleeping 9 hours a night. To clarify: this entails you need to spend more than 9 hours in bed per night. You might not fall asleep instantly or might have sleep disturbances.
- Experiment with your sleep duration. Find the sleep duration that best suits your lifestyle while also maximizing your quality of life and gains. You’ll be surprised at how much of an impact sleep can have on you.
- You’re a bad arbiter of how much you sleep and/or should sleep. Try sleeping more for a few weeks and see how it impacts you and your performance.
- Meditation and regular physical activity can also help out a ton with sleep quality and duration. Various supplements may also be useful.
Some suggest that you should just sleep 7 hours a night, and you’ll be golden. They’ll insist that sleeping any more than 7 hours would simply be a waste of time, and that you’d be better served doing something else instead of sleeping. In fact, one could argue that there is a widespread belief that sleeping for more than a certain period of time is regarded as laziness, despite a plethora of research showing that productivity, motivation and cognitive performance are drastically impeded by inadequate sleep. Sleeping insufficient amounts may be becoming increasingly socially acceptable and even desirable, in spite of the many and much documented benefits adequate sleep presents. Some would argue that cultural, technological and social changes have all contributed to making us care less about sleep, despite how beneficial adequate sleep is to our health and well-being.
Now that we know how much sleep, or lack thereof, can affect results when training, it’s time to ask the following questions;
How much should you sleep, and how does one optimise sleep?
How does resistance training impact sleep? “The effect of resistance exercise on sleep: A systematic review of randomized controlled trials” Kovacevic et al. (2017)
- “Chronic resistance exercise improves all aspects of sleep, with the greatest benefit for sleep quality.” Kovacevic et al. (2017)
- The effect of resistance training on sleep was attenuated when concurrent training was employed (both aerobic and resistance training) suggesting that there might not be much additional benefit to sleep of adding resistance training to aerobic exercise. This may be due to a mechanistic overlap in the way these two forms of exercise benefit sleep quality.
- The acute effects of resistance training on sleep were unclear.
- Chronic resistance training also helps with anxiety, depression and stress.
- Overall, the largest benefits of resistance training were observed for higher frequency (defined as sessions per week) and higher intensity (defined as minutes per session) conditions.
- The effect sizes for improvements in sleep quality were moderate-large. Improvements in sleep quality that large are relatively rare in the sleep literature – hence, this review concludes that resistance training may constitute a viable long-term treatment for sleep disturbances.
Overall, resistance training seemed to improve all aspects of sleep. The improvements were smallest in sleep duration, with the most common improvements observed in sleep efficiency (how much of the time spent in bed is spent asleep), sleep latency (how long it takes you to fall asleep), sleep quality (subjective ratings), and mid-sleep disturbances.
There also seemed to be a tendency for improved sleep quality as frequency and intensity of resistance training increased. However, there weren’t enough studies on these topics to test the hypotheses.
Notably, Effect Sizes for improvements in sleep quality (subjective) were moderate (ES=0.5) to large (ES=0.8), while pharmacological management only results in small to moderate (0.2-0.5) improvements.
A small retrospective note on last week’s article
In last week’s article, we primarily looked at 3 studies.
- The first study reviewed the literature on the impact of sleep deprivation on resistance training performance. As a consequence of sleep deprivation, performance decrements were observed across several studies.
- The second study investigated injury rates in adolescent athletes in relationship with sleep duration. This study suggests that injury rates decrease linearly, all the way up to (at least) 9 hours of sleep a night. When extrapolating these findings, however, it must be kept in mind that these subjects were relatively young, meaning they might require more sleep to reduce injury risk than older athletes.
- The final study was experimental and its topic was weight loss in relationship with time spent sleeping. Sleeping 5.25 hours a night resulted in a worse fat:LBM weight loss ratio and RMR than sleeping 7.5 hours a night. This points towards there being a positive impact of sleep on body composition, at least during weight loss, with benefits reaching up to at least 7.5 hours of sleep a night.
We also outlined several mechanistic explanations for the negative impact inadequate sleep has on training results.
In addition to the studies highlighted last week, several other studies suggest that sleep extension (increasing sleep duration) leads to increased performance in various sports:
- Sleep extension from 7.14 to 8.85 hours leads to improved tennis serving accuracy and subjective ratings of sleepiness. This might be taken to mean that increasing sleep from ~7 to ~9 hours increases your ability to perform complex athletic skills.
- Sleep extension from 6.66 to 8.45 hours of sleep leads to improved reaction time, shooting accuracy, sprint times and subjective mood and sleepiness ratings amongst collegiate basketball players. This study is particularly relevant to our purposes as sprinting is an expression of power that is tightly linked to your ability to produce force. Hence, this study suggests that amongst several other performance indicators, power (and force) production are likely increased by extending sleep duration from ~6.5 to ~8.5 hours a night.
When you combine these findings with last week’s discussion, it seems very likely that sleeping at least 9 hours a night will be necessary to optimise performance and results. There is a convincing body of research proposing that at least 9 hours a night are required to optimise performance – keep in mind that’s 9 hours of sleep, not time spent in bed. That means you need to spent at least 9 hours in bed a night to perform near your best. Additionally, it remains to be determined whether the benefits of sleep extension actually stop at 9 hours a night.
Note that there is no “one size fits all” sleep duration. The amount of sleep you need depends on many factors such as training, age and stress, and way too many other things. As such, take this series of articles as an evidence-based invitation, from me to you, to sleep as much as is beneficial to you. This more than likely means you ought to sleep more – although that is not the case for everyone.
I don’t feel qualified enough to talk at length about sleep hygiene. Nevertheless, here’s a link for sleep hygiene recommendations. They *might* help with sleep duration and various sleep quality aspects.
A final addendum for those currently sleeping relatively little (ie. less than the recommended amount for their age): you’re probably not aware of just how much your lack of sleep is messing you up. You tend to be a bad judge (1, 2) for how much you’re sleeping. So, even if you think you’re sleeping sufficiently to maximise quality of life and results in the gym – try sleeping more. You just might find you benefit from it.
Sleeping more offers a wide range of benefits. If you’re not sleeping as much as you should be, which can be over 9-10 hours depending on the demands of your sport and daily life, the overwhelming majority of your life will be enhanced as a consequence of sleeping more.