Sleep is essential for our physical and mental health, but did you know that there are different stages of sleep? Let's explore the four stages of sleep and what happens at each stage. We'll also discuss how much sleep people need determined by age.
The Stages of Sleep:
There are four stages of sleep: NREM (non-rapid eye movement) stages 1, 2, and 3, and REM (rapid eye movement) sleep. Each stage is important for different reasons, and a complete sleep cycle lasts around 90 minutes.
NREM Stage 1:
This is the lightest stage of sleep and typically lasts for around 5-10 minutes. During this stage, our body starts to relax, and our brain waves slow down. We may experience hypnic jerks or sudden muscle contractions during this stage, which may cause us to wake up temporarily.
NREM Stage 2:
This stage lasts for around 20 minutes and is characterized by a further drop in brain activity and body temperature. Our heart rate and breathing rate also slow down during this stage. We spend the most time in this stage of sleep, and it's crucial for consolidating memories and learning.
NREM Stage 3:
This is the deepest stage of sleep, also known as slow-wave sleep. It lasts for around 30 minutes and is crucial for physical restoration and repair. During this stage, our blood pressure drops, and our breathing becomes slow and regular. Our muscles relax, and our body releases growth hormone, which is essential for tissue repair and growth.
REM Sleep:
This is the stage where we dream and is essential for cognitive restoration and emotional processing. REM sleep typically occurs 90 minutes after falling asleep and lasts for around 10-20 minutes. During this stage, our brain activity increases, and our eyes move rapidly back and forth. Our muscles become paralyzed, which prevents us from acting out our dreams.
How Much Sleep Do You Need:
The amount of sleep people need varies depending on age. Here's a breakdown:
- Infants (0-3 months): 14-17 hours
- Babies (4-11 months): 12-15 hours
- Toddlers (1-2 years): 11-14 hours
- Preschoolers (3-5 years): 10-13 hours
- School-age children (6-13 years): 9-11 hours
- Teenagers (14-17 years): 8-10 hours
- Adults (18-64 years): 7-9 hours
- Older adults (65+ years): 7-8 hours
Conclusion:
Sleep is essential for our physical and mental health, and understanding the different stages of sleep and how much sleep we need is crucial for our overall well-being. By getting enough sleep and ensuring that we go through all the stages of sleep, we can improve our memory, concentration, and mood, and reduce the risk of health problems such as obesity, diabetes, and heart disease.