最近の米作農民のエネルギー消費量と疲労に関する実証的研究

抄録

It is considered that the physical load of the farmers in our country is being decreased according to the progress of mechanization in the agricultural works. However the actual conditions of the physical load of them are not yet confirmed enough. In the present study, the author aimed to determine experimentally the energy expenditure throughout the year and the grade of fatigue in busy seasons on the rice farmers in the present time. The experimental subjects in the study consist of six marriged couples who mainly engaged in rice farming in a district of Nagasaki. In the farming fields and their homes a series of the time atudies were carried out during 3 days monthly through the year, energy metabolism was measured for their agricultual activities on the method of Douglas bag, and daily energy expenditure was determined. In the busy seasons for rice planting, flicker fusion frequency, threshold of tendon reflex, near point, Donaggio's reaction and Na/K in urine were repeatedly determined, in order to evaluate the fatigue in the seasons. The results were compared with those obtained by Sekiguchi and others in the former time of 1949-1950 when the rice farming work was less mechanized.
(1) Daily farming times were about 5hours in men, and 3.8hours in women, on average in year.
(2) The obtained values of relative metabolic rates (RMR) on many farming activities were almost the same as those recently reported by other authors. RMRs were determined by the author on some of the new works, which in mordern rice farming had appeared.
(3) On some typical farming works being done seasonally, the values were calculated for mean RMR during a few hours when the subjects were in successive different elementary activities for farming and at times in rest, from the result of time studies and determined RMR value of each elemental activity.
(4) Mean daily energy expenditure in men were 2664Cal through a year 3440Cal in spring of busy season and 3220 Cal in autumn, likewise that in women 2374Cal, 2650Cal and 2502Cal respectively. This annual mean value of 2664 Cal in the males is lower by 550Cal than that of 3200Cal by Sekiguchi. It is obvious that mechanization in rice farming works has decreased energy expenditure in the farmers.
(5) The ranges of the variations in above mentioned three physiological function tests were within five percent during the busy seasons, and the change of the fliker values according to that of farming hours was less than that in the papers reported when the mechanization in agriculture was not so progressed as present. Thus, it is suggested that the fatigue of the rice farmers in the present time are lowered due to the mechanization of the agricultural works.