Association between lifestyle and physical activity level in the elderly: a study using doubly labeled water and...

Physical activity level (PAL) is associated with all-cause mortality in the elderly. However, few studies have attempted to clarify the relationship between lifestyle and PAL in the elderly. This study aimed to examine the determinants of PAL in the elderly in terms of behavioral patterns and exercise intensity, and to validate the simplified physical activity record (sPAR).

Thirty healthy, elderly individuals, aged 64-87 years, participated in the study. Total energy expenditure (TEEDLW), physical activity energy expenditure (PAEEDLW), and PAL (PALDLW) were calculated based on doubly labeled water (DLW) and measured basal metabolic rate. Physical activity was recorded using the sPAR.

PALDLW was significantly correlated with PAL estimated by sPAR (r = 0.588, P < 0.001). Good agreement was observed between TEEDLW (1,860 ± 373 kcal/day) and TEE estimated by sPAR (1,854 ± 377 kcal/day) (r = 0.825, P < 0.001). Good agreement was also observed between PAEEDLW (552 ± 242 kcal/day) and PAEE estimated by sPAR (562 ± 240 kcal/day) (r = 0.666, P < 0.001). The high PALDLW group had significantly shorter durations of 'sleeping time and rest periods' and 'daily life sedentary activities', and significantly longer durations of 'bicycling with moderate speed', 'housekeeping with standing', 'gymnastics, tai chi, stretching' and "swimming, hill climbing, fast jogging" than the low PAL group (P < 0.05).

The sPAR provides valid estimates of TEE and PAEE in the healthy elderly. The results suggest that engaging in housekeeping or sports activities for longer and being less sedentary may increase PALDLW in healthy elderly individuals.