To nap or not to nap? Whether napping will work for you depends on a range of factors, such as lifestyle, sleep cycle length, culture, and, most importantly, the length of your snooze. If you like to nap, you are not alone. Napping is part of the culture in many countries: around 51 percent of people worldwide habitually enjoy 40 winks in the daytime.
When it comes to napping. one size definitely doesn't fit all. If you are sleep deprived, a nap can be helpful or even essential for making it through the day. However, for those with other sleep issues, a nap may make it harder to fall asleep at night. For most of us, the timing and length of our nap will largely determine how beneficial it is to our sleep routine.
Between 1 p.m. and 4 p.m., most people experience an increase in sleepiness, triggered by a slight drop in core body temperature. A nap of 30 minutes or less around this time allows you to benefit from a burst of Stage I and 2 sleep, which is good for mental and physical alertness.
Napping for 30 minutes or less can reduce stress and lower the risk of cardiovascular problems like heart attacks and strokes. One study showed that napping three times a week for 30 minutes led to a 37 percent decreased risk of dying from heart disease.
A brief nap can be beneficial for those with excessive daytime sleepiness, including people suffering from sleep apnea(呼吸暂停) or narcolepsy, shift workers, and people with jet lag. Studies show that short naps can help improve or reset a disrupted circadian rhythm (昼夜节律).
Naps can interfere with insomnia(失眠) treatment, which involves restricting daytime sleep to increase the likelihood of sleeping solidly at night.
Be cautious about naps of more than 30 minutes. Waking from the deep-sleep stages results in sleep inertia, a super-dizzy state where brainwaves are slow and it takes longer to adjust to the awake state.
A recent study has found that napping for more than 60 minutes a day increased the risk of type 2 diabetes by 50 percent.
