economy class syndrome 经济舱综合征

Economy class syndrome: The formation of blood clots in veins deep within the legs -- deep vein thrombosis -- occurring during (or just after) a long airplane flight, especially in economy class (tourist class) where there is the least space allotted per passenger and one's legs tend especially to be immobilized for lack of leg room. 

“经济舱综合征”指的是在乘飞机长途飞行后，或刚刚下飞机时，腿部形成深静脉血栓，特别是乘坐经济舱旅行时，因为经济舱的座位非常狭小，由于缺少腿部空间，人们的腿部无法活动开来。

The economy class syndrome is not confined to that class on a plane. It is recommended that all persons traveling on air flights, irrespective of which class they are in, drink lots of water and move their legs by walking whenever possible and by periodically flexing and extending their ankles, knees, and hips to minimize the risk of economy class syndrome. Deep vein thrombosis is potentially serious and can even have fatal consequences. 

在搭乘飞机旅行时，并非只有经济舱的乘客才会面临这种问题。一般建议所有搭乘飞机的乘客，不管是头等舱、商务舱还是经济舱，都要多喝水，有可能时就要走一走活动双腿，定时扭扭脚踝，转转膝盖和臀部，尽量减少患上经济舱综合征的风险。深静脉血栓有很大的潜在危险性，甚至有可能致命。