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Sleep stages and their importance to your health

  • Published
  • By Kevin Egger
  • Hill AFB Health Promotion Coordinator
(Editor’s note: This is part three of a four-part series on the importance of sleep. Next week’s commentary will focus effective ways of enhancing your sleep hygiene and ways to help start your day off physically and mentally refreshed.)

Through the night your body should follow through 4-5 cycles of predictable stages of sleep, designed to optimize your mental and physical recovery.

One sleep cycle will follow the basic pattern of: stage 1, stage 2, stage 3, stage 4, and back up to stage 2. After stage 2, you will progress into the final step of a complete sleep cycle, which is called your Rapid Eye Movement, or REM, stage.

Each of these stages are necessary for your body to efficiently recovery both physically and mentally. One stage is not more important than another and any failure to repeatedly pass thorough each stage will result in some form of imbalance.

Stage 4 and the REM stages are currently the most researched as they are thought to play a vital roles in your physical and mental recovery.

During stage 4 your body releases key growth (anabolic) hormones and scientists believe this is when we physically repair and rebuild our bodies. In addition, during this stage your brain conducts repeated cleansing/detoxification cycles.

In studies where mammals are prevented from getting sufficient stage 4 sleep scientists have seen a significant increase in the prevalence of Alzheimer’s disease. Initially you will spend about an hour in stage 4, and each time you revisit this stage throughout the night the duration gradually decreases.

However, sleep disruptions during the night can result in resetting this timer and lead to inefficient durations for all different stages of sleep.

The REM stage is known for helping you learn and memorize. Unlike stage 4, the duration of REM gradually increases each time you cycle back to it.

Unfortunately, like Stage 4, sleep disruption can cause your REM duration to reset and likely prevent optimal mental recovery/memory collection. Effective REM duration accounts for about 25 percent of a good nights’ sleep.

One of the major ill effects of alcohol is that it inhibits REM stages from occurring. You might be asleep, but your recovery quality of sleep will be poor.

Insufficient sleep results in an increased level of mental and physical stress. More stress can mean more alcohol and more alcohol again will lead to an amplified amount of poor sleep and insufficient mental recovery.

Efficient sleep will result in cycling through all stages 4 to 5 times each night. As discussed, a disruption in sleep can negatively impact your ability to recover both mentally and physically.

If all goes as designed, you will awaken naturally every morning after having cycled through each of these stages. Optimally, you will awaken at the end of your final REM stage.

If you use an alarm to wake up each morning and, it goes off during your deepest state of sleep (stage 4), you’ll likely start your day off being very drowsy and a little grumpy.

There are many different devices on the market today that can generically assess our sleep efficiency and sufficiency resulting in a general overview of how well you are sleeping.

For sleep scientists the jury is still out on how well these devices work. They are diligently using the results of their sophisticated sleep study labs to help program these electronic devices to give users the best information possible.

Your Hill Air Force Base Health Promotion department offers Healthier Sleep, Healthier You classes on the fourth Tuesday of each month. In addition, our team is available to conduct flight- and squadron-level briefings on sleep and various other healthier lifestyle topics.

Call 801-777-1215 for additional information.