Ideally, you won’t even need an alarm clock to wake up at the proper time. If you’re getting enough sleep, your body will wake up on its own.

During the night, we cycle through four stages of sleep. Stage one and stage two sleep are considered light sleep, as our bodies prepare to enter a deeper slumber. Stage three sleep is known as slow-wave sleep, when the body carries out repairs and growth. Finally, stage four or rapid eye movement (REM) sleep is when we dream.

It typically takes about 90 minutes to cycle through all four stages of sleep, with time spent in REM sleep increasing as the night goes on. To wake up feeling well-rested, we must get sufficient amounts of both slow-wave and REM sleep.

We feel most refreshed when we wake up during light (stage one or two) sleep. By contrast, waking up during slow-wave sleep can cause feelings of grogginss and waking up from a vivid dream during REM sleep may be disorienting.

In an attempt to time the alarm with the end of a sleep cycle, some people calculate their bedtime by counting backwards from their preferred wake-up time. However, it’s important to note that sleep cycles can vary in length, even within the same night, and disruptions or difficulties falling asleep can throw off the schedule.

A more sustainable way to train your body to wake up at the right time is to keep a consistent routine, practice proper sleep hygiene, and ensure you get enough hours of sleep overall. Monitoring how you feel when you wake up within the context of this routine can help you identify areas that you might need to adjust. A wearable device or smartphone app may help you track your sleep architecture so you can better plan your night.

GIVE THE GIFT OF SLEEP: HEALY WATCH