The impact of real-time remote cardiac rehabilitation (CR) on health and disability-related outcomes and its correlation with physical function are unknown. We compared the effectiveness of real-time remote CR with that of hospital-based CR on physical function improvement and physical functions of improvement (Δ) to clarify the relationship between health and disability at baseline. Patients with cardiovascular diseases (CVDs) were enrolled (n = 38) in this quasi-randomised controlled trial and underwent 4 weeks of hospital-based CR, followed by 12 weeks of remote or hospital-based CR based on quasi-randomised allocation. Patients were assessed at baseline and after 12 weeks of remote or hospital-based CR using the shortened version of the World Health Organization (WHO) Quality of Life scale (WHOQOL-BREF) for subjective satisfaction, WHO Disability Assessment Schedule (WHODAS2.0-J) for objective performance, and cardiopulmonary exercise test for physical function and peak oxygen uptake (peak VO ). The trends in measured variables from baseline to the post-CR stage were analysed. Sixteen patients (mean age, 72.2 ± 10.4 years) completed remote CR, and 15 patients (mean age, 77.3 ± 4.8 years) completed hospital-based CR. The post-CR physical function differed significantly between the groups (Δ VO , 2.8 ± 3.0 versus 0.84 ± 1.8 mL·min ·kg ; p < 0.05). The differences in post-CR changes in the WHOQOL-BREF scores between the groups were insignificant. The post-CR changes in the WHODAS2.0-J scores were significantly lower in the remote CR group than in the hospital-based CR group (ΔWHODAS2.0-J score, -8.56 ± 14.2 versus 2.14 ± 7.6; p < 0.01). Forward multiple stepwise regression analysis using overall data showed that the intervention method (β = 0.339, p < 0.05), baseline cognition (β =  - 0.424, p < 0.05), and social interaction level (β = 0.658, p < 0.01; WHODAS2.0-J) were significant independent contributors to Δpeak VO (r  = 0.48, F = 8.13, p < 0.01). Remote CR considerably improved physical function and objective performance in patients with CVDs. Remote CR can be used to effectively treat stable patients who cannot visit hospitals. This interventional trial was registered at the UMIN-CTR registry (trial title: Development of remote programme for cardiac rehabilitation using wearable electrocardiograph; trial ID: UMIN000041746; trial URL: https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000046564 ; registration date: 2020/09/09).