What happens when you sleep? How much sleep do you really need?
Sleep is vital for recharging your batteries and staying healthy. It’s for your mind as well as your body. While humans might one day evolve to a point where sleep isn’t necessary, for now it’s absolutely essential. Anyone who says ‘I don’t seem to need more than a few hours’ sleep every night’ is kidding themselves. For optimum performance of body and mind, 7 to 8 hours of sleep a night is the goal.
Working when you’re tired is dangerous
When you don’t get the required dose of shut-eye, it’s harder to be productive, work safely and make good decisions. Like a quad bike with faulty spark plugs, your brain’s neurons aren’t firing properly. Fatigue is a risk factor in farm injuries – statistics show that most farm accidents happen between 2 and 4pm, when a poor night’s sleep shows up as the ‘afternoon slump’.
What happens when you sleep?
- Your muscles get a chance to repair themselves and grow stronger
- Your brain rests and recovers, so that it can focus the next day
- Memories are consolidated, making it easier to remember and learn new things
- Hormones are released to regulate energy, appetite and growth
Your body is run by a clock
Sleep patterns are dictated by your biological clock (circadian clock), which works on a 24-hour light-dark cycle. It’s natural to be awake during daylight hours and sleep when it’s dark. The hormone melatonin is released after dark, causing drowsiness. Levels of melatonin reduce as sunrise gets closer, preparing you to wake up and be alert.
Three types of sleep, then repeat
People sleep in 90-minute cycles and during a good night’s sleep you can expect 4 to 5 of these cycles. Sometimes you will wake between cycles; at other times you seamlessly start a new cycle. Each cycle consists of several parts:
1. Light sleep
2. Deep sleep – this is when the good work is done – repair and growth work for your bones, muscles and immune system
3. REM sleep – the dreaming stage that stimulates the brain regions used in learning