Credit: BrilliantEye
Time for Sleeping (2 of 2)
LaMar Sheppard, DC, CSCS, QME
Sleeping is a dynamic process that consists of integrated stages with each supporting key functions in the body and brain. The stages are broadly divided into two categories: non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep.
1. NREM Stage 1: The initial stage where individuals sleep lightly and are easily awakened. It lasts for a few minutes and serves as a transitional phase between waking and deep sleeping.
2. NREM Stage 2: In this stage, the body progresses to slightly deeper sleeping while internal temperature and heart rate decrease, brain activity slows down and eye movement ceases. NREM Stage 2 plays a role in memory consolidation and cognitive processing while describing a major portion of total sleep time.
3. NREM Stage 3: The deepest stage of NREM sleep that is characterized by slow delta brain waves. Brain activity reaches its lowest frequency during this stage while the body undergoes important restorative processes including the release of growth hormones and tissue repair. This stage is critical for physical recovery and feeling energized upon waking.
4. REM Sleep: A distinct stage marked by vivid dreaming, increased brain activity and rapid eye movements. REM sleep fosters emotional processing, memory consolidation, and cognitive function.
The sleep cycle transitions between these stages throughout the night. On average, a cycle consumes 90 to 120 minutes before the next begins with most individuals completing four to five cycles within eight hours nightly. Many lifestyle interventions recognize individualized variables such as food sensitivities and injury history. In contrast, sleeping routines are invariable because everyone benefits from at least seven hours of sleeping to complete up to five cycles.
Allied fields provide evidence that supports the impact of sleep quality. In coordinated shifts, industrial workers produce and transfer goods throughout an entire day. Occupational health recognizes that working outside daylight hours increases the risk of diabetes, heart disease and obesity. This cohort experiences partial sleep normally while their routine disrupts the body’s internal clock which manages waking and sleeping states. Sleep maintenance bolsters the quality of life and our capacity to accumulate meaningful experiences.