Could weak legs be making it hard to breathe? new study investigates

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria for ILD Patients: * Age 40-80 years (inclusive) * A multidisciplinary diagnosis of idiopathic pulmonary fibrosis (IPF), idiopathic fibrotic nonspecific interstitial pneumonia (NSIP), chronic hypersensitivity pneumonitis (HP), or unclassifiable ILD with a differential diagnosis that consists of the above diagnoses * Fibrosis on high resolution computed tomography (HRCT): honeycombing, reticulation, or traction bronchiectasis * Appropriate candidate for pulmonary rehabilitation * 6 minute walk distance 50m or more * Oxygen saturation ≥ 92% by pulse oximetry at rest while breathing room air * Clinically stable for the preceding 6 weeks * Can fluently read and write in English Inclusion Criteria for Healthy Controls: * Age 40-80 (inclusive) * Normal pulmonary function (80-120% predicted) * No lung or cardiovascular disease * Can fluently read and write in English Exclusion Criteria for the ILD patients: * Contraindication to exercise testing (e.g. significant cardiovascular, musculoskeletal, neurological disease) * Other significant extra-pulmonary disease that, based on clinical assessment, could impair exercise capacity and/or oxygenation * Forced vital capacity (FVC) less than 50% or Diffusion capacity for carbon monoxide (DLCO) less than 25% * Concurrent or recent participation (less than 6 months) in a pulmonary rehabilitation program * Use of prednisone greater than 10 mg/day for more than 2 weeks within 3 months of the first study visit * Significant emphysema (less than 10% volume on HRCT or FEV1/FVC less than 0.70) Exclusion Criteria for Healthy Controls: * Currently smoking or previously smoked more than 10 pack-years * Any medical conditions that prevents them for exercising safely * Cardiac pacemaker or any metal or electronic inside the body