1. Unidade de Fisiologia Pulmonar, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil;
2. Respiratory Investigation Unit, Division of Respirology, Department of Medicine, Kingston Health Sciences Centre, Queen’s University and Kingston General Hospital, Kingston, Ontario, Canada;
3. School of Kinesiology and Health Science, Faculty of Health, York University, Toronto, Ontario, Canada; and
4. Setor de Função Pulmonar e Fisiologia Clinica do Exercício, Universidade Federal de Sao Paulo, Sao Paulo, Brazil