The sleep cycle takes about 90 minutes and will be completed 4 or 5 times during the night.
If your sleep is broken before reaching stages 3 and 4 (the most restful and restorative stages) your body probably won’t feel the benefits of sleep, and you might notice some of the effects of sleeping problems.
The Four Stages of Sleep
Stage 1- Falling Asleep.
Our brain waves begin to slow down and our muscles relax.
Stage 2- Light Sleep.
Brain waves slow even further
Stage 3- Transition to Deep Sleep.
Body temperature drops and our muscles relax fully.
Stage 4- Deepest Sleep.
A full stage of the deepest sleep where the body remains in the state it reaches in stage 3.