Electrocardiographic and other clinical correlates of walking ability in older women

The purpose of this study was to examine how resting electrocardiographic (ECG) and other clinical variables, which can be included in a routine clinical examination, predict walking ability in older women. Three hundred and twenty women (63-75 years) without overt cardiac diseases and apparent mobility limitations were studied. Measurements performed were clinical examination (standard 12-lead resting ECG, assessment of physical activity level, presence of chronic diseases, use of beta-blockers, body mass index (BMI), ability to squat, resting blood pressure) and six-minute walking test. Participants walked 533+/-75 m in the six-minute walking test. The best electrocardiographic predictors of long walking distance were high TV(5) and TII, but their explanation rates were small (4.5% and 3.8%, respectively). In hypertensive participants (systolic blood pressure=SBP> or =160 mmHg), the respective values were 9.3% and 5.8%. The best predictors of long walking distance were ability to squat without limitations and low BMI (15.5% and 13.6%, respectively). Altogether the studied variables explained 36% of the variation in walking distance. The data gathered in clinical examination give useful information for the assessment of walking ability in relatively healthy older women. Resting ECG does not give clinically significant additional information for the assessment in subjects without overt cardiac disease.