2007 Volume 73 Issue 4 Pages 127-136
Physical activity patterns were investigated in ten elderly men (mean age 72.1 years) living on a remote isolated island that has undergone a simultaneous rapid decrease in population and rapid growth of the elderly population. Acceleration monitoring, recorded every two minutes, was conducted for each subject on seven consecutive days to determine their total daily energy expenditure (TEE). Anthropometry, blood pressure, and handgrip strength measurements were made. Consequently, four men were judged as obese and six as hypertensive. According to a Japanese standard reference, the mean daily physical activity level (PAL) of the subjects was categorized as moderately low. By contrast, the mean daily step frequency (STEP) exceeded the national standard average (4, 787 steps/day) for the same age-sex group. Moreover, six men exceeded the target value for elderly men (6, 700 steps/day). Intra-day variation in the physical activity intensities measured every two hours reflected the subjects' lifestyles;however, no particular tendency was observed in the daily variation in the PAL. All the subjects were retired from regular employment, and no longer worked on a schedule. Consequently, no significant difference was observed in PALS between weekdays and weekends. Bland and Altman analysis clarified that the TEE calculated using the accelerometer was underestimated, which supports previous studies. The significant relationships between the physical activity indices (PAL and STEP) and blood pressure or handgrip strength suggest that walking andpromoting physical fitness have important roles in maintaining and increasing PALS in the elderly. Physical activity may be a key factor in preventing hypertension in the elderly.