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Sleep and exercise: why it matters


It’s a pretty well-known fact that sleep is one of the most important things when it comes to maintaining good overall health. It’s also not a secret that many of us aren’t getting anywhere near enough of it.

The 2013 Great British Bedtime Report found that 40% of Britons were getting less than the 6-9 hours of nightly sleep recommended by the NHS.[1]

That’s bad news, considering the NHS warnings that regular sleep deprivation increases the risk of obesity, heart disease, and diabetes, in addition to lowering sex drive, causing depression, harming immunity, and much more.[2]

But how about the importance of sleep for fitness and exercise?


Sleep is when the body really recovers

Any type of exercise works by placing a strain on the body and inducing micro-injuries which will need to be repaired. If the repairs go according to plan, the body will come back stronger and more able to handle the strain the next time around.

Sleep seems to be the time when your body really kicks into recovery mode. Studies have found that a massive spike of Growth Hormone occurs during the nocturnal hours, but only when the subjects are properly asleep.[3]

Whether you’re a runner or a weight lifter, the fact is that sleep is essential for recovery and progression.


Poor sleep promotes fat gain

A 2009 review[4] of the scientific data noted that sleep deprivation is directly tied to increased levels of the hormone ghrelin (responsible for hunger), decreased levels of the hormone leptin (responsible for satiety), decreased insulin sensitivity (meaning fat is stored more easily), and more.

What this means at the end of the day, is that sleep deprivation creates a perfect storm of bad conditions which lead directly towards obesity, and which will sabotage even the best-laid weight loss plans.

More hunger, combined with more fat storage, is not what you’re after.


Sleep deprivation means hitting the wall faster

Research has found[5] that, although moderate sleep deprivation doesn’t appear to impact cardiovascular response or muscle strength directly, it does reduce the time it takes to experience exhaustion.

Additionally, perceived exertion is always higher in sleep deprived individuals – meaning that regardless of your physical state, any exercise you do will feel much more difficult and uncomfortable.

The bottom line of all of this is that being sleep deprived means you’ll have less energy for a prolonged workout – which is especially bad for endurance athletes – and will also feel much worse about getting up, heading to the gym, and doing your workout in the first place.

None of that sounds like a recipe for success.







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