You may think that guzzling cups of coffee is the answer to staying awake, but as it turns out taking those short power naps is a more effective way of not falling off to sleep, especially for young people.
The finding is based on a study conducted by Patricia Sagaspe, PhD, of the Clinique du Sommeil at CHU Pellegrin in Bordeau, France, who studied 24 people, 12 young (between 20-25 years of age) and 12 middle-aged (between 40-50 years of age).
As a part of the study the volunteers first drove 125 highway miles in the daylight, between 6:00 and 7:30 p.m. Then, in a test of the effects of coffee and napping on night-time driving, participants drove another 125 miles between 2:00 and 3:30 a.m. after having a cup of coffee with 200 mg of caffeine, a placebo (a cup of decaffeinated coffee with 15 mg of caffeine) or a 30-minute nap.
Dr Sagaspe then kept a check for inappropriate line crossings, self-perceived fatigue and sleepiness and polysomnographic recordings.
Once analysed, the results showed that the number of inappropriate line crossings was significantly increased when driving in the evening.
She also found that compared with a placebo, both coffee and napping reduced the risk of inappropriate line crossings in young and middle-aged participants.
A significant interaction between age and condition showed that napping led to fewer inappropriate line crossings in younger than in middle-aged participants. During napping, young participants slept more and had more delta sleep than middle-aged participants.
Self-perceived sleepiness and fatigue did not differ between age groups, but coffee improved sleepiness, whereas napping did not.
"The potential effect of age on response to sleepiness countermeasures should be considered in populations exposed to extended wakefulness. According to their age or individual physiology, subjects should implement their best countermeasures to sleepiness at the wheel," said Dr. Sagaspe.
On average, most adults need seven to eight hours of sleep each night to feel alert and well-rested.
The study is published in the December 1 issue of the journal SLEEP.