Altered Sleep Time Difficult for Body

A study involving sleep for the National Aeronautics andSpace Administration (NASA) indicated that the body has a hardertime adjusting to different sleep times than originally perceived.NASA has been instructing astronauts to begin going tobed 2 hours later than normal over a period of time to prepare fortheir desired sleep schedule. Reporting in Aviation, Space andEnvironmental Medicine (December 2004), lead investigatorTimothy Monk, PhD, said this may not be the best approach.

In the first phase of the study, the participants shifted sleep on 2-hour blocks, but the result was poor sleep quality and not being asalert. The results of this part of the study showed that the body onlyadjusts itself by 1 hour a night—not the 2 of NASA's current recommendations.The second phase of the study altered sleep in 30-minute blocks; the final phase in progress now will alter sleep in oneabrupt movement. Dr. Monk said that the study can be applied toanyone who must change schedules.

"Many of us find that we have to change our sleep schedule,perhaps to accommodate work or school start times, or achange in our commute time," he said. "We often wonder if weshould make the change all at once, or more gradually overseveral days or weeks. This research has the eventual aim ofhelping us make that decision."