1 Department of Respiratory Physiology Deputy Directorate of Ancillary Diagnostic Services, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío villegas (INER), Instituto de Desarrollo e Innovación en Fisiología Respiratoria (INFIRE), Tlalpan 4502, Colonia Sección XVI, Tlalpan, Ciudad de México, CP 14080, México. Electronic address: drgochis@iner.gob.mx.
2 Division of Pediatric Pulmonology, Department of Pediatrics, Division of Pulmonary, Critical Care & Sleep Medicine, Department of Medicine, National Jewish Health, National Jewish Health Exercise and, Performance Breathing Center, 1400 Jackson Street, Box J-320, Denver, CO 80206, USA. Electronic address: exercise@njhealth.org.