How Much Sleep Do We Really Need?
According to the US Military Each individual nap(A short sleep) should be long enough to provide at least 45 continuous minutes of sleep, although longer naps (2 hours) are better to acquire a daily total of 8 hours of sleep.
This means that it is possible to use a longer nap in order to get the required 8 (or 7, if you wish) hours of sleep.
NASA performed a study in which they tested whether taking longer naps in conjunction with a few hours of regular sleep would work better in the long run.
Research found that it was not danger to go all week long with only 5 hours of sleep and then take a longer sleep on weekends for 7 or 8 hours. And it should be happen occasionally but not regularly.
At a minimum you need to listen to your body. Look for changes in your energy level throughout the day, bedtimes, how easily you get up, unplanned naps, dreams, and sleep quality.
