The brain has its own waste removal system which is similar to the bodies lymphatic system called the Glymphatic system.
When we fall into a deep sleep, the hippocampus part of the brain will shrink by 200%. This leaves room for cerebral spinal fluid to wash beta-amyloid and other metabolic waste out of the brain.
This happens during the deep non rem sleep cycle which is the early stage of sleeping. It’s important not to wake up or disrupt this process as it will affect how much fluid is released into the brain cavity.
The Glymphatic system operates most efficiently when the body is horizontal. Falling asleep or dozing off upright will severely limit the release of spinal fluid.
For optimal results sleeping on your side with legs slightly raised will increase the Glymphatic wash process.
Zone 2 training, where you are training at a low-level heart rate (being able to talk but not sing) has also been shown to support the Glymphatic system.
This can be done on a stationary bike or cross-trainer for 45mins to an hour, 3 times per week.
You will also get the added benefit of making your mitochondria more efficient in utilising fat oxidisation for energy.
Each night if you are not getting enough sleep the waste product (beta-amyloid) accumulates, leading over time the risk of Alzheimer’s Disease.