所谓脑力劳动是指其职业以脑力劳动或神经紧张性工作为主的人（如含科研、设计、行政管理、新闻、写作、教学、会计等行业）。这些人一般姿势单调，体力运动量少，思维却异常频繁，能量消耗多。大脑生物学研究表明：一个成年人大脑重量仅为体重的２．５％，但却有全身血量... The so-called mental work refers to the occupation of mental work or nervous work-based people (such as scientific research, design, administration, journalism, writing, teaching, accounting and other industries). These people generally monotonous posture, physical exercise less, thinking is unusually frequent, more energy consumption. Brain biology research shows that: an adult brain weight is only 2.5% of body weight, but there is the body’s blood volume ...