Fatigue Management a Three Part Series – Circadian Rhythms and the Night Shift

Some of our body systems run on a 24-hour cycle known as circadian rhythms. These rhythms are regulated by the light that comes into our eyes from our surrounding environment.

Our body systems that run on circadian rhythms do have a huge impact on us. They impact things like:

  • Memory
  • Alertness
  • Physical coordination
  • Reaction time
  • Decision making
  • Behaviour
  • Emotional stability

The average person is designed to be the most awake and alert between 7am – 10pm. That is when all our body systems are functioning to make us alert and aware of the environment around us. There is a small dip in our energy levels and alertness that occurs between 1 – 3pm but besides that we are designed to be at our most alert and awake between 7am – 10pm.

Between 10pm – 6am is when our body systems are doing everything they can to put us into sleep mode. During this time, we will be less alert and aware of our environment. Also, our coordination and reaction time and our memory and decision making during this time are not at their prime.

So how does this impact workers in the workplace? It impacts workers who work the night shift.

I worked the night shift at a group home and a sandblasting / coating company back in the day and I noticed the impact of my circadian rhythms during those night shifts. I was not as alert, awake or sharp in making decisions as I was during the day.

If you work the night shift, do you notice the impacts on your circadian rhythms?


Source: CSSE