Incidence and Factors Associated with Suboptimal Exercise Workload Progression in Cardiac Rehabilitation: A Retrospective Cohort Study.

Abstract

Background: Improving cardiorespiratory fitness is a central goal of cardiac rehabilitation (CR), yet exercise workload progression varies substantially. We aimed to characterize changes in treadmill workload during CR and determine the frequency of, and the factors associated with, suboptimal progression. Methods: This retrospective cohort study included 180 patients enrolled in an outpatient CR program. Treadmill exercise workload was quantified in metabolic equivalents (METs) from recorded speed and grade using estimated oxygen-consumption equations. Using prespecified exploratory thresholds, suboptimal progression was defined as an absolute increase of Results: Median workload increased from 3.07 METs (IQR 2.40-4.01) during the initial four sessions to 3.90 METs (IQR 2.93-5.56) during the final four sessions ( p Conclusions: More than half of participants demonstrated suboptimal treadmill workload progression despite significant overall improvement during CR. Routine monitoring of session-level workload may facilitate identification of patients with limited progression and support individualized adjustment of exercise prescriptions.