If you’re a chronic napper, you know that no two naps ever feel quite the same. Some leave you feeling groggy while others energize you.

So, is there such a thing as the perfect nap? And how much time should you nap for? We asked Amy Korwin, MD, a pulmonologist with Hartford HealthCare Medical Group.

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There’s no denying that naps can be beneficial.

In the right setting, naps can bring many benefits to your health.

“Naps can increase your alertness and improve your performance and reaction times,” explains Dr. Korwin. “They can also reduce fatigue or sleepiness and improve your mood.”

But keep your naps short.

Dr. Korwin recommends keeping your naps to no longer than 20 minutes to reap the most benefits, while avoiding the downsides.

“Longer naps reduce your sleep drive, making it harder for you to fall asleep easily at night. They can also lead to sleep inertia, or a groggy feeling and difficulty returning to a fully awake, alert state after the nap,” adds Dr. Korwin.

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And pick the right time of day for your nap.

Under most circumstances, napping should not occur in the late afternoon and early evenings.

Why? Napping later in the day can impact your ability to fall asleep at night.

“In the afternoon, your body experiences a natural circadian dip, or a dip in energy levels, making it an ideal time for napping,” explains Dr. Korwin.

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The potential downsides of napping.

There are potential downsides to consider. Some studies suggest longer naps are associated with more serious health outcomes, such as heart disease, depression and diabetes.

“Although it’s unclear whether napping causes these conditions or if it’s underlying health issues that lead to increased sleepiness and napping,” adds Dr. Korwin.

So, next time you’re in the mood for a cat nap, remember – early afternoon and 20 minutes maximum. Happy napping!