[The relationship of quality of life (QOL) with physical fitness, competence and stress response in elderly in Japan].

OBJECTIVES In order to evaluate the relationship of quality of life (QOL) with physical fitness, competence and stress response in the elderly population in Japan, a cross sectional field survey of elderly subjects was conducted. METHODS This survey was taken in Naguri village, Saitama. The data collected included physical fitness, competence, stress response and QOL in addition to demographic variables. As for physical fitness indexes, grip strength (GS), single leg balance with eyes closed (SLB), bar grip ping reaction time (RT), trunk flexion (RF), ten-meter walking time (WT) and vital capacity (VC) were measured. The SF-36 was used for QOL assessment. RESULTS A total of 120 elderly subjected participated to the survey. There were 42 males (73.5 +/- 5.74 years) and 78 females (74.2 +/- 6.17 years). The associations between physical health parameters in SF-36 and WT were highly significant: physical functioning (beta = -2.96, p < 0.001), role physical (beta = -3.64, p < 0.001), bodily pain (beta = -3.27, p < 0.001) and general health (beta = -3.14, p = 0.001). Psychological stress response had a negative correlation with social functioning (beta = -0.74, p = 0.024), role-emotional (beta = -2.34, p < 0.007) and mental health (beta = -0.97, p = 0.024) as determined by multiple regression analysis. The goodness-of-fit indexes of the structural equation model describing the relationships among physical fitness, competence, stress response and QOL indicated excellent fit to the data with GFI = 0.95 and AGFI = 0.88. Stress response showed relatively stronger influence on QOL than physical fitness or competence. CONCLUSION Although there were slight differences in degree of influence, physical fitness, stress response and competence were found to be clearly related to QOL in elderly subjects. To keep good QOL status, it is important to maintain good physical fitness and level of competence and to reduce stress response.