Resistance training combined with β-hydroxy β-methylbutyrate for patients with critical illness: A four-arm, mixed-methods, feasibility randomised controlled trial

Abstract

Objectives: This study aimed to assess the feasibility, safety, acceptability, and potential effectiveness of resistance training (RT) with or without β-Hydroxy β-Methylbutyrate (HMB) intervention program for ICU patients.

Design: Open-label, parallel group, mixed method, randomized controlled trial.

Settings: A tertiary general hospital in Fuzhou, China.

Methods: Participants were randomly allocated to one of four groups. The RT group received supervised multilevel resistance training (RT) using elastic bands, administered by trained ICU nurses. The HMB group received an additional daily dose of 3.0 g HMB. The combination group underwent both interventions concurrently, while the control group received standard care. These interventions were implemented throughout the entire hospitalization period. Primary outcomes included feasibility indicators such as recruitment rate, enrollment rate, retention rate, and compliance rate. Secondary outcomes covered adverse events, acceptability (evaluated through questionnaires and qualitative interviews), and physical function. Quantitative analysis utilized a generalized estimation equation model, while qualitative analysis employed directed content analysis.

Results: All feasibility indicators met predetermined criteria. Forty-eight patients were randomly assigned across four arms, achieving a 96% enrollment rate. Most patients adhered to the intervention until discharge, resulting in a 97.9% retention rate. Compliance rates for both RT and HMB interventions approached or exceeded 85%. No adverse events were reported. The intervention achieved 100% acceptability, with a prevailing expression of positive experiences and perception of appropriateness. The RT intervention shows potential improvement in physical function, while HMB does not.

Conclusions: Implementing nurse-led resistance training with elastic bands with or without HMB proved to be feasible and safe for ICU patients.

Implications for clinical practice: A large-scale, multicenter clinical trials are imperative to definitively assess the impact of this intervention on functional outcomes in this population.

Keywords: Feasibility studies; Intensive care units; Randomized controlled trial; Resistance training; β-hydroxy β-methylbutyrate.