Your sleep is broken down into three stages and REM sleep. Stage one is that time between being awake and falling asleep where you can easily be disturbed.
If you wake up during this stage, it’s likely you never fell asleep to begin with. Stage two is considered “average sleep.” We tend to spend half our night of sleep in this stage. Brain waves are slow and your heart rate and blood pressure regulate by slowing down. This means your heart and vascular system are resting. Stage three is our deepest sleep where our brain waves transform into slow, restorative, high-amplitude waves. Our body repairs itself during this stage. REM sleep is where we experience our most vivid dreams. The body is resting during this time but the brain is active as if we were awake.