Can I reset my body clock to run earlier or later?

Whether you have to get up earlier for a new job or you want to start exercising first thing for your health, it will take persistence to reset your sleeping pattern.

Your biological clock controls when you naturally sleep, wake, and feel most alert in any 24-hour period. The rhythm is influenced by external factors, but it is also programmed by your genes; each of us has a “chronotype” that we can’t simply override.

Scientists are discovering more about how genes affect our sleep/wake behavior. For example, early bird chronotypes appear to have a longer “PER 3” gene than night owls, which also hardwires early bird types to need more sleep. Most of us are intermediates who lean slightly toward either morning or night.

As you can’t beat your biology, it’s better to work with your body’s natural sleep/wake pattern rather than against it. For instance, will getting up an hour earlier for yoga class suit your chronotype? (to find out more.) If the answer is yes because you’re naturally an early bird, bear in mind that you will still need to go to bed an hour earlier to ensure your body gets enough restorative sleep.

Routine is critical, too; maintain any new sleep/wake schedule seven days a week. Unless you are an extreme chronotype, your body should gradually adapt to the new timetable as long as you consistently get enough rest.

MAKING THE SHIFT

• Introduce changes gradually. See below for a four-week plan to bring your body clock forward or back by an hour.

• To help your system fire up earlier, go outside into the daylight as soon as possible after you get up. And to reinforce an earlier body clock reset, try eating something right after you wake up. You may not feel like it at first, but do it every day and your biological clock will in time change its circadian pattern so that hunger will help wake you at the new earlier time.

• It isn’t possible to make major changes in your hard-wired clock—an hour either way is the most you can realistically aim for. A major lifestyle change, like permanent night shift work, will be more challenging. (See link for more on managing shifts and night work.)

Earlier reset for owls

To wake an hour earlier, set your morning alarm 15 minutes earlier than usual and go to bed 15 minutes earlier every night for a week. Repeat for three more weeks.

Later reset for birds

To wake an hour later, set your morning alarm 15 minutes later than usual and go to bed 15 minutes later every night for a week. Repeat for three more weeks.

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