ObjectivesGuidelines for exercise intensity prescription in Cardiac Rehabilitation (CR) are inconsistent and have recently been discussed controversially. We aimed (1) to compare training intensities between European CR centres and (2) to assess associations between training intensity and improvement in peak oxygen consumption (V˙O₂) in elderly CR patients.MethodsPeakV˙O₂, heart rate and work rate (WR) at the first and second ventilatory thresholds were measured at start of CR. Training heart rate was measured during three sessions spread over the CR. Multivariate models were used to compare training characteristics between centres and to assess the effect of training intensity on change in peakV˙O₂.ResultsTraining intensity was measured in 1011 out of 1633 EU-CaRE patients in 7 of 8 centers and the first and secondary ventilatory threshold were identified in 1166 and 817 patients, respectively. The first and second ventilatory threshold were found at 44% (SD 16%) and 78% (SD 9%) of peak WR and 78% (SD 9%) and 89% (SD 5%) of peak heart rate, respectively. Training intensity and session duration varied significantly between centres but change in peakV˙O₂over CR did not. Training above the first individual threshold (β 0.62, 95% confidence interval [0.25–1.02]) and increase in training volume per hour (β 0.06, 95%CI [0.01–0.12]) were associated with a higher change in peakV˙O₂.ConclusionWhile training intensity and volume varied greatly amongst current European CR programs, changes in peakV˙O₂were similar and the effect of training characteristics on these changes were small.