Effect of a 12-week home-based exercise training program on aerobic capacity, muscle mass, liver and spleen stiffness, and quality of life in cirrhotic patients: a randomized controlled clinical trial
Authors: Sirisunhirun Pavapol , Bandidniyamanon Wimolrak , Jrerattakon Yonworanat , Muangsomboon Kobkun , Pramyothin Pornpoj , Nimanong Supot , Tanwandee Tawesak , Charatcharoenwitthaya Phunchai , Chainuvati Siwaporn , Chotiyaputta Watcharasak 
Published: February 2022

Abstract
Background
Physical inactivity and sarcopenia are two important predictors associated with increased morbidity and mortality in patients with cirrhosis. At present, the benefit of a home-based exercise training program is not well established in cirrhotic patients. The main objective of this study was to evaluate the effect of a 12-week home-based exercise training program on aerobic capacity in cirrhotic patients.

Methods
This is a randomized controlled study. Patients with compensated cirrhosis were randomized by a block of 4 with concealed allocation to the home-based exercise training (n = 20) or control (n = 20). Both groups received protein supplementation (9 g/day) for 12 weeks. The home-based exercise training program included several aerobic/isotonic moderate-intensity continuous training exercises for 40 min per session, at least four times a week, with a total duration of 12 weeks. The heart rate was continuously monitored using a Garmin® watch. In the control group, patients received exercise instruction without active encouragement and continuous monitoring. The primary outcome was a change in the 6-min walk test from baseline. Secondary outcomes were the difference in thigh muscle thickness, liver stiffness, spleen stiffness, and quality of life.

Results
A total of 40 patients were enrolled prospectively. The mean age was 56.3 ± 7.8 years, with a male predominance of 65%. The mean body mass index was 25.23 ± 3.0 kg/m2, and all were Child–Pugh A. Chronic hepatitis B or C was the primary cause of cirrhosis. The baseline values were a 6-min walk test of 475 ± 70 m, liver stiffness of 15.3 ± 9.3 kPa, spleen stiffness of 29.8 ± 21.7 kPa, and thigh muscle thickness (average compression index) of 0.64 ± 0.2 cm/m2. All baseline characteristics between the two groups were not different except the mean muscle mass which was significantly higher in the home-based exercise training group (p = 0.03, 95% CI 0.01 to 0.17). At the end of the study, no significant difference in the 6-min walk test was observed (p = 0.36, 95% CI −15.5 to 41.7). Liver stiffness measurement significantly improved in both groups, but no significant difference between groups was demonstrated (p = 0.77, 95% CI −1.3 to 1.8). Thigh muscle thickness was not different between groups. The fatigue domain of the quality of life index was significantly improved in the home-based exercise training group compared with the control group (p = 0.05, 95% CI 0.00 to 0.67). No adverse events occurred in a home-based exercise training program.

Conclusions
A 12-week moderate-intensity home-based exercise training program in compensated cirrhotic patients significantly improved the fatigue domain of the quality of life index without an increase in adverse events. However, no benefit in terms of aerobic capacity, thigh muscle mass, liver stiffness, and spleen stiffness was demonstrated.
Trial registration: Thai Clinical Trials Registry number TCTR20190926002, 26/09/2019 (Retrospectively registered).