ENERGY-COST OF PHYSICAL ACTIVITIES IN HEALTHY ELDERLY WOMEN

In recent studies, daily physical activity ratios (PARs) greater than the Food and Agriculture Organization/World Health Organization/United Nations University (FAO/WHO/UNU) reference value of 1.5 have been rep orted for elderly men and women. The purpose of this study was to inve stigate whether a high PAR in elderly subjects can be explained by a h igher energy cost of physical activities (EEact). To this end, 12 elde rly women aged 69 to 82 years, completed physical activity diaries dur ing a 2-day stay in a respiration chamber. From these diaries, total d aily energy expenditure (TEE) in the calorimeter was estimated (TEEfac ) using FAO/WHO/UNU PARs for physical activities and measured resting metabolic rate (RMR). TEEfac was 7.0 +/- 0.9 MJ/d (PAR, 1.35 +/- 0.06) . TEE was also measured in the chamber (TEEcal) and was 8.3 +/- 1.3 MJ /d (PAR, 1.60 +/- 0.16). TEEfac was 14.8% +/- 8.1% lower than TEEcal. To investigate whether the underestimation of TEEcal was due to a high er EEact in the elderly women as compared with the FAO/WHO/UNU referen ces, EEact of six specific activities ranging from sitting at rest to walking on a treadmill at self-chosen speed was measured with a ventil ated-hood system. Individually measured PARs of the six activities wer e similar to FAO/WHO/UNU reference PARs. This study suggests that in e lderly women a high TEEcal is not explained by EEact during nonstandar dized physical activities performed at self-chosen speeds, Whether the se results can be extrapolated to the free-living environment needs to be investigated further. Copyright (C) 1995 by W.B. Saunders Company