Abstract
Analyzing the accident reports of forestry work, we found that there are significant relationships between certain accidents such as "Fall" and "Mishandling", and the forestry workers' decreasing movement abilities with age such as "Agility" and "Balance" and so on. Results from the physical fitness tests showed that the forestry workers' "Muscular endurance" (maximum oxygen intake) and "Muscular strength" (grip strength) decrease at a lower rate with age than those of Japanese standards; however, the motion abilities such as "Balance" (close-eye foot balance) and "Agility" (jumping reaction time) decrease at a faster rate with age than the Japanese standard. An investigation of a questionnaire given to the advanced-age forestry workers showed that the abilities of "Seeing", "Hearing", "Writing speed" and "Memorization" decrease at a faster rate with age while that of "Muscular endurance", "Muscular strength of leg" and "Flexibility" decrease at a slower rate with age. Based on the study of the relationships between the human motion ability and the result from the analysis of the movement of feet, hands and waist, the range of angle and the angular velocity between backbone and leg, and between arm and backbone, we could conclude that the physical motion in piling and felling the trees, among various physical activities in forestry work, highly requires the physical abilities such as "Balance" and "Agility", yet these traits weaken with age.
