Effects of flying and of time changes on menstrual cycle length and on performance in airline stewardesses.

摘要: Log books for recording menstrual cycles were issued to 119 stewardesses joining British Overseas Airways Company. None had previously irregular and none was taking oral contraceptives. Cycle lengths recorded on their 1st year of flying transmeridian routes. The irregularity cycle length significantly greater than normal in 8 subjects abnormally short only 1 (p less .05) . In another study 7 from the preceding experiment other subject temperatures times a day away meal times. Later they divided into 2 groups. group time zone change (TZC) immediately advanced hours later hours. On release test after 4 days third 8-hour advance made resynchronize with local time. groups there no (NTZC). Both kept controlled environment unit where temperature humidity constant. No natural lighting present contact outside world permitted. Work-load tasks carried out sessions duration during study. these work-load efficiency TZC lower NTZC group. usual diurnal body but clear apparent Average daily loss sleep 1.07 grou p 2.99 This difference considered sign ificant .05). degree deprivation may have caused inferior performance this subjected TZCs. disturbance circadian rhythm also been factor. These findings be important scheduling cabin crew so that remain at best operational duty