Physical Characteristics of Okinawan Diving-Fishers in Relation to Work History

Abstract

Thirteen anthropometric and physiological measurements of 84 male diving-fishers in Ishigaki City, Okinawa Prefecture were conducted. The first comparison was between the present data and the corresponding data of six other groups of Japanese muscular workers, and the second focused upon the differences within the Ishigaki diving-fishers in relation to their work history. The Ishigaki diving-fishers were characterized by larger biceps circumference, while their grip strength was inferior. For the second analysis, the Ishigaki diving-fishers were grouped into three: the first (group B) has exclusively carried out breath-hold diving, the second (BD), breath-hold diving and then mask-and-hose diving, and the third (BH) breath-hold diving followed by hand-line fishing. Significant inter-group differences existed only among the older fishers aged 50 to 59 in the four variables analyzed. Comparing with group BH, group B was higher in weight/height ratio, larger in biceps circumference, stronger in grip strength, and lower in heart rate. These differences are likely to have attributed to cumulative effects of their work.