Change in Peak Oxygen Uptake Predicted by the Moderate 1-km Treadmill Walking Test After Walking Training in Outpatients With Cardiovascular Disease

Abstract

Purpose: The purpose of this study was to determine the ability of the moderate 1-km treadmill walking test (1km-TWT) to predict changes in peak oxygen uptake (V˙ O2peak) in patients with stable cardiovascular disease (CVD) during an exercise-based secondary prevention program. Methods: Sixty-four male outpatients with stable CVD (age 64 [41-85] yr) performed the 1km-TWT before and after an 8-wk walking training program. Patient V˙ O2peak was estimated using a sex-specific equation including age, body mass index, 1km-TWT performance time, and heart rate (V˙ O2peakEST). Forty-one patients completed a maximal cardiopulmonary treadmill test (CPX) for direct V˙ O2peak determination (V˙ O2peakMEAS). The training prescription consisted of moderate-to-high intensity supervised walking for 30-40 min/session, and an additional 2-4 times/wk of unsupervised home moderate walking sessions between 20-60 min at the end of the program. The walking intensity was based on the results of the 1km-TWT. Results: Patients participated in an average of 14 of the 16 supervised sessions. An overall significant improvement in V˙ O2peakMEAS and weekly recreational physical activity levels were observed. No differences were observed between V˙ O2peakMEAS and V˙ O2peakEST. Compared with CPX results, the 1km-TWT underestimated the V˙ O2peak increase after the exercise intervention (mean difference −0.3 mL/kg/min, P > .05). Conclusions: The 1km-TWT provides a reasonably accurate and simple tool to predict changes in V˙ O2peak due to moderate walking training in male outpatients with CVD. These findings contribute to the growing body of evidence supporting the use of the 1km-TWT for exercise testing and training purposes in the context of cardiac rehabilitation/secondary prevention programs.