If you wake up feeling tired when your alarm clock rings, chances are you are right in the middle of a sleep cycle.
Sometimes, it's better to set your alarm clock just a little earlier or later in order to enjoy a fully recuperative night.
One night's sleep typically includes between four and six sleep cycles, of about 90 to 100 minutes each.
The frequency and length of these cycles vary between individuals.
Age, gender, diet, exposure to screens, and physical fitness are all factors which will affect the quality of rest you get.
To be at the top of your game, you should ideally rack up five full cycles, or a seven-and-a-half hour sleep.
To figure out the exact duration of your sleep cycles, the best thing to do is to write down the time when you fall asleep and the time when you wake up.
It's much easier to remember to do this very helpful assessment on a holiday or a long weekend.
When you have a few days' times down, you will be able to work out the time that you should head to bed, based on the time you need to wake up the next day, calculating in 90-minute segments.
If you plan to wake up at 8 a.m., for instance, the ideal bedtime hour would be 11 p.m. or half past midnight, in order to enjoy a recuperative nine-hour or seven and a half-hour night.
SLEEPING EARLY DOESN'T ALWAYS WORK
Some people insist on going to bed early, to avoid being tired the following day.
But unfortunately, this may prove to be counterproductive, especially for night owls.
Instead, pay attention to actual signs of tiredness: yawning, frequent blinking, or a general loss of muscle tone.