Abstract
PURPOSE
Cardiopulmonary exercise testing (CPET) is used to determine the etiology of unexplained exercise symptoms in otherwise healthy patients and those with well defined cardiopulmonary disease. Test results vary by baseline physical activity levels which are difficult to assess objectively.
METHODS
We performed submaximal exercise testing on 40 physically active, healthy control patients as part of a prospective trial to evaluate the exercise response in patients with chronic fatigue syndrome. All patients provided a self-assessment of fitness using a series of previously validated visual analogue scales (VAS). We evaluated the relationship between baseline fitness and physiologic response to exercise.
RESULTS
Mean age and BMI for the group were 30.7±8.8 and 27.0±3.6 respectively. There were 25 males (62.5%), 23 caucasians (57.5%) and 13 (32.5%) African Americans.
On a VAS from one to ten with ten being optimal, patients rated their current endurance, fitness and muscular strength at 7.8±1.5, 7.9±1.1 and 7.3±1.9. Self-assessment of endurance was significantly correlated with maximum respiratory rate (r=-0.34, p=0.03), fitness showed a trend toward correlation with heart rate reserve (r=0.27, p=0.09) and muscular strength was significantly correlated with peak heart rate (r=-0.43, p=0.01), heart rate reserve (r=0.33, p=0.04) and O2-pulse at VO2 max (r=0.37, p=0.02).
Female assessment of fitness and muscle strength showed good correlation with work rate achieved (0.40 and 0.53 respectively).
CONCLUSIONS
In a group of young, physically fit patients self assessment is correlated with aerobic fitness measured on symptom targeted, sub-maximal exercise testing. VAS scores for muscular strength seemed to be a better predictor of the cardiac response to exercise than were scores for endurance or fitness.
CLINICAL IMPLICATIONS
Visual analogue scales can be used to provide a baseline assessment of fitness, In conjunction with other factors known to predict responses to exercise these scales could theoretically help better define normality for a given patient.
Self-Assessment Using a Validated Visual Analogue Scale Predicts Response to Submaximal Exercise Testing, by T Hauser & A Holley in Chest Journal, 1 October 2013
