Exercise And Recovery Ventilatory Responses Between Individuals With Neuromuscular Disease And Healthy Adults

Neuromuscular diseases (NMDs) impair physical activity and increase cardiopulmonary disease risk, yet exercise and recovery prescriptions for this group lack established guidelines. PURPOSE: This study aimed to quantify cardiopulmonary responses at ventilatory threshold (VT) during exercise and recovery in patients with NMD. METHODS: Participants included patients with NMD and categorized into "NMD I" (LGMD, DMD, Dystrophinopathy, BMD, Pompe) and "NMD II" (DM1, DM2, FSHD, Dysferlinopathy, SMA3), along with age-matched healthy controls. Cardiopulmonary exercise testing (CPET) was performed using a Cosmed-K5 wearable metabolic analyzer and a Keiser total body trainer, with VT determined via piecewise regression from VO2 and VCO2. Linear mixed-models analyzed VO2, VE/VCO2, and RER at VT, with phase (exercise and recovery) and group as fixed factors and participants as random effect. RESULTS: Significant findings included a reduced VO2 at VT for NMD I and NMD II (Estimate: -11.27, -8.28, p < 0.01) with further reduction during recovery compared to controls (-5.98, p < 0.01). RER at VT indicated significant metabolic shift post-exercise (Estimate: 0.54, p < 0.01), with NMD I resulting in a lower RER at VT recovery (Estimate: -0.39, p < 0.01). VE/VCO2 at VT was significantly higher in NMD I compared to controls (Estimate: 5.68, p < 0.01), with a pronounced increase during recovery (Estimate: -3.774, p < 0.01). CONCLUSION: Our findings highlight cardiorespiratory exercise and recovery differences at VT between NMD groups and controls, with recovery showing critical disparities. These insights are essential for understanding impact of central vs peripheral recovery responses in different disease types enabling a more tailored exercise program and promote safe exercise dosing and recovery for patients with NMD.