Sleep is an active process consisting of multiple stages that repeat throughout the night. Most people experience five to six sleep cycles per night, with each cycle lasting approximately 90 minutes.
Deep sleep: physical recovery
During deep sleep:
- Heart rate slows
- Blood pressure decreases
- Muscles relax
- Physical recovery takes place
Deep sleep is particularly important for tissue repair, immune function, and overall physical restoration. Research suggests that insufficient deep sleep may contribute to higher blood pressure and poorer cardiovascular health.
REM sleep: mental recovery
REM (Rapid Eye Movement) sleep is the stage most closely associated with dreaming.
During REM sleep:
- The brain becomes highly active
- Memories are consolidated
- Emotions are processed
- Learning and cognitive function are supported
REM sleep plays an essential role in mental wellbeing and emotional resilience. A lack of quality sleep can make people more sensitive to stress and emotional challenges.