Feasibility and Reliability of Functional Muscle Tests in Lung Transplant Recipients

OBJECTIVE: This study investigates the feasibility, reliability, and correlations of recommended functional tests in lung transplant recipients shortly after surgery. DESIGN: This is an observational study. METHODS: Fifty patients (28 females) performed well-standardized maximum isometric back extension in a sitting position, handgrip strength, and Biering-Sørensen endurance tests shortly before discharge from the acute hospital, shortly thereafter, and 2 mos later after subacute rehabilitation. RESULTS: Back extension testing was well feasible, but only two thirds of the patients could perform the Biering-Sørensen test at baseline and they experienced a greater number of minor but no major adverse events. Absolute reliability measures and the intraclass correlation coefficients were excellent for the strength (0.97–0.98 [0.95–0.99]) and good for the endurance tests (0.69 [0.26–0.87]). Handgrip revealed high correlation with back strength (≥0.75) but not with Biering-Sørensen scores. CONCLUSIONS: Well-controlled maximum back strength testing is feasible and reliable, and the scores are highly correlated with grip strength in lung transplant recipients shortly before hospital discharge. The Biering-Sørensen test should be limited to patients without dominant weakness and/or fear. Future research should investigate whether grip instead of back extension strength can safely be used for proper exercise prescription.