Effects of high-load and low-load resistance training in patients with coronary artery disease: rationale and design of a randomised controlled clinical trial

INTRODUCTION: Resistance training (RT) combined with aerobic training (AT) enhances the effects of cardiac rehabilitation (CR) in patients with coronary artery disease (CAD). However, it remains to be investigated which type of RT (high loads (HLs) vs low loads (LLs)) is more efficacious in improving exercise performance, cardio-metabolic health and quality of life. METHODS AND ANALYSIS: A randomised, controlled, clinical trial will enrol 20 patients with CAD into each of three study arms (total 60 patients): HL-RT (70%–80% of one repetition maximum (1-RM)) combined with AT; LL-RT (30%–40% of 1-RM) combined with AT and AT alone as standard care. Primary outcomes (maximal aerobic capacity, maximal leg isometric strength) will be assessed at baseline and after 36 training sessions. Other outcomes will include acute haemodynamic responses to LL-RT and HL-RT, body composition, physical performance, blood biomarkers (lipids, glucose metabolism, inflammation, growth factors), physical activity and quality of life. The intention-to-treat principle will be used to analyse the data. ETHICS AND DISSEMINATION: The study design and protocol have been approved by the National Medical Ethics Committee of Slovenia (registration number: 0120-573/2019/15). The study will be conducted in accordance with the Declaration of Helsinki. The results of the study will be published as peer-reviewed manuscripts and congress presentations, communicated with patients and the clinical community, and shared through posts on social media. The findings of the study will be disseminated among the national CR clinical community (CR centres, Slovenian association of coronary clubs) with active participation of the patients enrolled in the study. This study will expand our knowledge of RT in combination with AT in CR. We expect to find different effects of HL-RT versus LL-RT, with implications for RT strategies in rehabilitation of patients with CAD. TRIAL REGISTRATION NUMBER: NCT04638764.