Influence of jet lag and cabin floor vibration by transmeridian flight on air crews

Research Project

Project/Area Number	08670404
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Hygiene
Research Institution	Nippon Sport Science University
Principal Investigator	SAKURAI Tadayoshi Department of Physical Education, Nippon Sport Science University, Professor, 体育学部, 教授 (80122620)
Project Period (FY)	1996 – 1997
Project Status	Completed (Fiscal Year 1997)
Budget Amount *help	¥1,600,000 (Direct Cost: ¥1,600,000) Fiscal Year 1997: ¥600,000 (Direct Cost: ¥600,000) Fiscal Year 1996: ¥1,000,000 (Direct Cost: ¥1,000,000)
Keywords	jet lag / cabin vibration / circadian rhythm / acrophase / surface EMG / surface body temperature / body activity / サーカディアンリズム / 頂点移動 / 機体振動 / 活動量 / 低周波騒音 / 機内湿度 / 自律神経機能 / 体温頂点位相変動
Research Abstract	The air crews who worked in the transmeridian flight are influenced by in-flight work and the work environment in addition to the time lag by their flight. After returning from the eastward flight (North American route from Japan), the acrophase of their body temperature moved 2-3 hours forward, and those moved 4-6 hours backward in the westward flight (European route from Japan). The acrophase in the eastward flight returned in 3-4 days after returning to home, and that recovered about four days in the westward flight. Head heaviness, skin dryness, tiredness and cervicobrachial pain exceed 70% as a symptom. Their body activities were longer in eastward flight than in the westward flight time during in-flight work. The heart beat increased and decreased by the activity of in-flight work. The low frequency noise under 50Hz was about 93dB in the passengers cabin and the vibration on the cabin floor was about 102dB.Though the cabin temperature was between 24-26ﾟC, cabin humidity became 20% or less 1 hour after departure, and decreased down to about 10% at 2 hours later. Their surface body temperature rose and the integrated surface electromyogram (EMGs) increased with the body activity. The crew activity time in the eastward flight was longer than that in the westward flight because of leaving in daytime at the eastward flight. In general, the working hours and the working time influenced on in-flight workers though it was relatively unsuitable in the westward flight by rephase of the body rhythm with the time lag rather than in the eastward flight. As for the vibration of cabin floor, main components was seen by frequency 30-125Hz. 30-40Hz vibration was generated by the rotation of the turbine of the engine. EMGs grew according to the shake of the plane floor though a main EMGs activity was chiefly caused by the body action of in-flight work.