Spring forward, fall back—even though the clocks change by only an hour during Daylight Savings Time, the effects can be noticeable. This is especially true in the spring, when people lose an hour of the day and that hour is often subtracted from time spent sleeping. If you’re already somewhat sleep-deprived, giving up just one hour of shuteye can negatively impact how you feel and function during the day, perhaps even compromising your alertness and reaction time while driving.
It’s as if you end up with a mild case of jet lag. Your body’s internal clock (or circadian rhythm) may be thrown off course, which can affect how much sleep-inducing melatonin is released and when. Plus, before springing forward, it was probably light outside when you woke up, which helped your body’s internal clock activate brain regions that are involved in stimulating alertness and energy. After springing forward, you get an extra hour of light in the late afternoon but the early morning hours are dark, which means that your body’s internal clock may not be quite ready to wake up when the alarm goes off. These changes can make it harder to get going in the morning and perhaps more difficult to turn in at your usual hour.
Within a few days, you should adjust to the new time schedule naturally as your circadian rhythm catches up to your new reality. If you have the foresight to plan ahead, it helps to prepare for losing that hour of sleep by going to bed 15 to 20 minutes earlier than usual each night in the days leading up to the time change. If you don’t, at least turn in earlier on the night of the time change to try to recoup some of that lost shuteye.
To help your brain and body make the shift more quickly, it also helps to sleep in for an extra half hour on the Sunday morning after the clocks change and expose yourself to sunlight early in the morning. If it’s difficult to get natural sunlight in the morning where you live, consider using a light box or dawn simulator to enhance mental and physical alertness. Think of this as tricking your internal clock into believing that it’s sunny outside and it’s time to get moving. As the weeks progress, this will become less of an issue as the days gain more hours of natural light.