1 (Also called) civil year the period of time, the calendar year, containing 365 days or in a leap year 366 days. It is based on the Gregorian calendar, being divided into 12 calendar months, and is reckoned from January 1 to December 31.
40 FACTS ABOUT SLEEP YOU PROBABLY DIDN'T KNOW... (OR WERE TOO TIRED TO THINK ABOUT). - The record for the longest period without sleep is 18 days, 21 hours, 40 minutes during a rocking chair marathon. The record holder reported hallucinations, paranoia, blurred vision, slurred speech and memory and concentration lapses.
The National Sleep Foundation's sleep guidelines recommend seven to nine hours for the average adult. One night of missed sleep will probably do little harm, but the cumulative effect of poor sleep will have a negative impact on your muscles.