Resting VO2, maximal VO2 and metabolic equivalents in free-living healthy elderly women.

BACKGROUND & AIMS: Maximal VO2 (VO2max) and metabolic equivalents (METs) decline with aging due to body composition and cardiovascular modifications. However, a detailed evaluation of these variables for this population has not been done. The aim of this study was to evaluate VO2max and METs in healthy elderly women, and to establish whether the calculated resting VO2 (3.5 ml/min/kg) underestimates the true METs. METHODS: 81 females over 65 years old attending a twice-weekly mild fitness program were studied. Body composition was measured by DEXA. VO2max and resting VO2 (VO(2rest-meas)) were measured by indirect calorimetry. METs were measured (METs-meas) using the VO2max/VO(2rest-meas) ratio, and calculated (METs-cal) from the ratio between measured VO2max and calculated resting VO2 (3.5 ml/min/kg of body weight). RESULTS: The VO(2rest-meas) and VO2max measured by indirect calorimetry were 2.9+/-0.4 ml/min/kg and 17.5+/-2.8 ml/min/kg, respectively. The METs-meas were higher than the METs-cal (6.1+/-1.2 vs 5.0+/-0.8; p<0.001). The 25th-75th percentile range of measured METs was 5.2-6.8. CONCLUSIONS: Our study confirmed that, in elderly women, METs values ranging between 5 and 7 are compatible with an acceptable physical activity. The estimated resting VO2 (3.5 ml/min/kg) does not appear to be applicable to elderly women, because it underestimates the real METs in this population. [ABSTRACT FROM AUTHOR]