Fig. 6From: The Contribution of Individual Exercise Training Components to Clinical Outcomes in Randomised Controlled Trials of Cardiac Rehabilitation: A Systematic Review and Meta-regressionRelationship between the highest intensity of exercise prescribed (as a percentage of maximal heart rate) and the relative risk of percutaneous coronary intervention compared to usual care (p = 0.047). Each intervention is represented by a circle; the size of the circle is proportional to the number of participants undertaking that intervention. A log RR of >0 represents an increase in risk and <0 a decrease. Circles coloured green represent interventions for which the highest intensity was only prescribed for brief periods during interval training. Circles coloured purple represent interventions for which the highest intensity was only prescribed during the work periods of circuit trainingBack to article page