Diaphragm fatigue in young adult males and its characterization during exercise

• Grant number: 16/08999-5
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• Start date: September 12, 2016
• End date: September 11, 2017
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Audrey Borghi Silva
• Grantee: Bruno Archiza
• Supervisor: Andrew William Sheel
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Institution abroad: University of British Columbia, Vancouver (UBC), Canada
• Associated to the scholarship: 14/10145-9 - A randomized controlled clinical trial of the effects of respiratory muscle training on improving exercise tolerance in women's soccer players, BP.DD

Abstract

Diaphragm fatigue (DF) occurs during high-intensity endurance exercise in healthy humans. This could be a limiting factor to exercise tolerance, triggering dyspnea, peripheral effort perceptions and the inspiratory muscle metaboreflex. Nevertheless, some questions about DF remains unclear. Thus, we sought to investigate whether DF has a progressive increase during high-intensity exercise or if there is a threshold for its onset. Also, if DF is reproducible for a given high-intensity exercise duration. Ten healthy young adult male subjects will be recruited. After a comprehensive clinical evaluation, oxygen uptake (VO2) will be assessed through a cardiopulmonary exercise test (CPET) in a stationary cycle ergometer. Subsequently, all subjects will perform a constant load cycling test set at 85% of VO2 in order to determine time limit until exhaustion (Tlim) and, 10 and30 min after the test, DF will be assessed through measurements of gastric and esophageal pressures (Pga and Pes, respectively) and cervical magnetic stimulation (CMS). Lastly, the last visit will be similar to the second, but the test will be interrupted halfway of Tlim (½ Tlim) and DF will be assessed in the same way. This study will bring important physiological elucidations related to DF during high intensity exercise in healthy young adult males. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ARCHIZA, BRUNO; WELCH, JOSEPH F.; GEARY, CAITLIN M.; ALLEN, GRAYSON P.; BORGHI-SILVA, AUDREY; SHEEL, A. WILLIAM. Exercise-Induced Diaphragmatic Fatigue Is Determined By The Work Of Breathing In Healthy Men. MEDICINE AND SCIENCE IN SPORTS AND EXERCISE, v. 50, n. 5, p. 1-pg., 2018-05-01. (14/10145-9, 16/08999-5)

ARCHIZA, BRUNO; WELCH, JOSEPH F.; GEARY, CAITLIN M.; ALLEN, GRAYSON P.; BORGHI-SILVA, AUDREY; SHEEL, A. WILLIAM. Temporal characteristics of exercise-induced diaphragmatic fatigue. Journal of Applied Physiology, v. 124, n. 4, p. 906-914, APR 2018. (16/08999-5)