Are you a morning person, or do you thrive in the evening? Do you take cover in your house all winter only to emerge refreshed when warm weather arrives in the spring? We may know that animals have biological clocks that determine which times of day they're active. These clocks also help geese to know when to migrate and determine when bears hibernate.

But did you know that humans also have biological clocks? Ever wonder why teenagers are cranky about waking up early for school? It's not just to make everyone around them miserable. Teenagers are not wired to go to bed early and wake up early.

Your husband who is so cheerful in the morning may annoy you as you struggle to get out of bed. But when 10 p.m. hits and your spouse is falling asleep watching the news, you have enough energy to tackle a household project.

We do not all function with the same internal clock.

Tick tock

That internal biological clock, also called circadian rhythms, regulates when we feel sleepy and awake each day. According to the National Sleep Foundation, we have internal circadian biological clocks, just like animals. Our circadian rhythms fall and rise at different times of the day, according to the foundation, and cause us to feel especially alert at certain points of the day.

When adults and teenagers get enough sleep, somewhere between 7 to 10 hours, the circadian rhythm is part of a normal, healthy schedule. However, interruptions to the circadian rhythm, like jet lag, can put our bodies at odds with natural sleep patterns.

Set Your Biological Clock

While your internal circadian rhythm operates on its own, you don't have to let it make you tired or irritable. Follow these tips to help you feel your best.

  • Make sure to allow for enough sleep time every night. That means if you're setting the alarm an hour early for a meeting tomorrow, find a way to hit the sheets an hour earlier tonight.
  • If at all possible, let your body sleep when it wants when traveling. If you can schedule your 12-hour flight during the night, you may be able to sleep on the plane and arrive at your destination feeling refreshed.
  • If you can, schedule meetings when you know you and your team members are most alert. If you suffer at 2 p.m., it might not be the best time to schedule a meeting to brainstorm ideas.
  • Know your creative window. When do you usually feel most creative? That's the time to start new projects that require you to think outside the box or test your skills. For example, if you do your best thinking at 9 a.m., start a new project in the morning.
  • Save your tedious projects. No one likes to file or organize and clean up. Save this work for times when you know you won't be creative or times you know are down times. If you hit a slump at 2 p.m., use that time to organize your desk or file papers.