Training hard and eating well… but still not seeing results? If you’re skimping on sleep, it could be the reason:

First, inadequate sleep lowers growth hormone production. As it’s responsible for metabolic rate,
lean muscle mass and muscle restoration, to compromise it’s full potential equally compromises post training gains -
your body burns less fat, your muscles don’t grow and you don’t appear as taut.
And even if you are sleeping those precious 7-9 hours, you could still be facing an uphill battle if you’re not sleeping at the right time:
Journal of Endocrinology and Metabolism reports growth hormone is primarily synthesised between 10pm-2am.

Next factor to discuss is (hormone) cortisol: research shows it increases by 37% after one night of inadequate sleep.
Catabolising (eating) muscles, this contributes to poor muscle tone, slows metabolism and encourages the storage of fat.

As a result of the two factors above, scientists have found fat loss heightens by 55% when you sleep 8.5 hours vs 5.5.
As all those tested were on a calorie and exercise controlled plan, admittedly, participants in the 5.5 hour group still lost weight -
however, they lost muscle rather than fat. In addition to lowering your metabolism, losing muscle
also restricts your ability to train at your peak in following sessions.

Finally, for those in a competitive sport, a Stanford study found a 9% increase in accuracy after adequate sleep
- quite possibly the difference between winning or losing. As sleep impairs your frontal cortex,
this could be due to a lack of concentration, slower processing speed or indecision - all adversely affected by poor sleep.

Further to the above, there are long term consequences of sleep deprivation too:
Clinical Journal of Sports Medicine reports injury risk to double for those sleeping less than 8 hours;
and for those chronically sleep deprived; they have a 40% lower longevity of sporting careers -
as noted by American Academy of Sleep Medicine.
Possible explanations include an increased injury likelihood, ongoing fatigue
or lack of motivation - all a direct result of sleep deprivation.

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