Patients with peripheral artery disease (PAD) often cannot attain a sufficient exercise intensity and/or duration to detect myocardial ischemia during graded exercise testing (GXT). An air ergometer (AE) may be an alternative to treadmill (TM) testing in these patients. We compared a TM GXT to an AE GXT in 20 PAD patients (12 males; 8 females; mean age: 62±11 years). Oxygen uptake (VO2), heart rate (HR), rate-pressure product(RPP), ratings of claudication, and perceived exertion (RPE) were measured during each 3 minute stage of exercise. Test endpoints were claudication intensity of 4/4 or RPE ≥ 18. Peak exercise parameters are shown below:Table Tests were terminated due to severe claudication in 14 during TM GXT and in 9 during AE GXT (p=0.2). In the 13 patients who had claudication on both tests, the pain occurred later on the AE (mean onset: 460±212 sec.) than on the TM (mean onset: 304±203 sec.; p<0.05). Half of the patients (10/20) attained a peak HR ≥ 85% on the TM and AE. Conclusion: Although VO2peak and HRpeak were similar between the 2 tests, patients with PAD exercised longer and attained a higher RPP on the AE compared with the TM. These data suggest that the Air Dyne GXT may improve the detection of CHD in patients with PAD who cannot exercise adequately on the treadmill.

Ambulation is integral to many activities of daily living, therefore, a walking test may be a good tool to evaluate functional ability in the elderly. The purpose of this study was to evaluate the safety of a 6 minute walk test in very old, independent adults, and to identify factors which contribute to test performance. Sixteen sedentary adults (86.8 ± 5.9 yrs.) completed a 6 minute walk test, a maximal cycle ergometer test with measurement of VO2, the Balance Scale (BS), a Physical Performance Test (PPT), the Up and Go, a 5 RM knee extension (KE) and a 5 RM leg press (LP). No injuries or adverse effects occurred. Means and standard deviations follow.Table To determine the contribution of these variables to walk distance, a standard regression model was developed. PPT and Up and Go correlated highly with each other (r=0.98; p<0.05), but PPT correlated more highly with walk distance (r=0.78 vs. r=0.70; p<0.05). BS, KE and LP were poor predictor variables (p>0.5). PPT and VO2 were independent predictors of walk distance, but neither was significant when both entered the regression equation. Individual equations are presented in the followingtable. Comparison of the two, revealed PPT to be the best predictor of walk performance (p<0.05). Conclusion: The 6 minute walk test is safe for use in the very old. Test performance is related to both maximal VO2 and PPT, although PPT is the best predictor of walk performance. The walk test may provide a surrogate for either of these measures.