Wikner A; Umea University, 901 87 Umea, Sweden.
Rinnstrom D; Johansson K; Bergman F; et al
Cardiology in the Young. 36(1):111-118, 2026 Jan.
BACKGROUND: Impaired muscle function, aerobic capacity, and fatigue are
common in individuals with Fontan circulation. Knowledge regarding the
effects of strength training in this population is limited. Therefore, the
study aimed to investigate the effects of strength training on dynamic
muscle function, aerobic capacity, and fatigue in adults with Fontan
circulation compared to matched controls.
METHODS: In this pilot non-randomised controlled trial, nine patients
with Fontan circulation (median age 28.9 years [IQR: 23.4-35.0], 44.4%
women) and nine age- and sex-matched controls completed a 10-week strength
training intervention. Dynamic muscle function was assessed through
shoulder flexion, heel rise, elbow flexion, and knee extension tests.
Aerobic capacity was evaluated using cardiopulmonary exercise testing, and
fatigue using the questionnaire Multidimensional Fatigue Inventory. All
assessments were conducted pre- and post-intervention. Within-group
changes were analysed using the Wilcoxon signed rank test and
between-group differences using the Mann-Whitney U test.
RESULTS: Patients showed improvements in all muscle function tests
post-intervention (shoulder flexions 39.3% [IQR: 18.9-69.7], p = 0.008;
heel rise 26.7% [IQR:17.5-58.1], p = 0.008; elbow flexions 57.1% [IQR:
50.0-173.8], p = 0.007; knee extensions 66.7% [24.3-92.9], p = 0.008). The
improvements were at comparable levels to controls. Only controls reported
reduced fatigue (-19.4% [IQR: -28.7, -10.5], p = 0.01), while patients
showed no change (-5.9% [IQR: -25.5, 3.2], p = 0.1). Aerobic capacity
remained unchanged. No severe adverse events occurred.
CONCLUSION: Strength training is safe and improves dynamic muscle
function in patients with Fontan circulation, with changes comparable to
those of healthy controls. However, the effect of strength training on
fatigue and aerobic capacity requires further
investigation.