Resistance training during cardiac rehabilitation improves physical performance in patients with coronary artery disease: a randomised controlled trial

Abstract

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Slovenian Research Agency Background Resistance training (RT) is an adjunct exercise therapy to aerobic training (AT) in cardiac rehabilitation, but it remains unknown whether the dose-dependent relationship between RT load (high load [HL] vs. low load [LL]) and improvement in anthropometry, body composition and physical performance exists in patients with coronary artery disease (CAD). Purpose The aim of our study was to investigate the effects of HL-RT and LL-RT on top of AT in comparison to AT on anthropometry, body composition and physical performance in patients with CAD. Methods A total of 79 patients with a stable CAD were randomised to HL-RT+AT (n = 21), LL-RT+AT (n = 19) or AT (n = 19) and performed 36 training sessions. Fifty-nine patients with mean (SD) age 61 (8) years and left ventricular ejection fraction 53 (9) % completed the study. AT progressed from 50 % to 80% of peak power output achieved at baseline cardiopulmonary exercise test, and RT progressed from 70% of one repetition maximum (1-RM) to 80% of 1-RM in HL-RT group, and from 35% of 1-RM to 40% of 1-RM in LL-RT group. We measured anthropometry (body mass, waist and hip circumference, and waist to hip circumference ratio), body composition (lean body mass and %, body fat mass and %, and phase angle) and physical performance evaluating upper muscle strength (arm curl and hand grip test) and lower muscle strength (five sit-to stand test, up-and-go test, heel raise test), mobility (gait speed test), flexibility (back scratch test, sit-and-reach test), balance (stork balance test) and submaximal endurance (6 min walk test distance) at baseline and post-training. Results Waist circumference and waist-to-hip circumference ratio decreased significantly following LL-RT (both p < 0.01), without post-training differences between training interventions in other anthropometry measures and body composition measures (all p > 0.079). HL-RT and LL-RT induced improvements in all physical performance measures, while AT alone did not improve gait speed, upper limb flexibility and performance of up-and-go test. HL-RT was associated with greater improvement in gait speed (+12 %, p =0.044), arm curl test (+13 %, p = 0.037) and time of Up-and-go test (+9 %, p <0.001) compared to AT group, while LL-RT improved more time of Up-and-Go test (+18 %, p < 0.001) and time of five sit-to-stands (+14 %, p = 0.016) compared to AT. There was no difference between HL-RT and LL-RT in post-training change of physical performance measures. Conclusions The addition of RT to AT is associated with greater improvements in submaximal muscle strength and mobility compared to AT and should be encouraged in future multimodal exercise-based cardiac rehabilitation.