Ventilatory mechanics in endurance athletes

The purpose of this study is to describe normal ventilatory mechanics during exercise in endurance trained and healthy untrained individuals, explore potential gender differences during exercise and investigate the impact of flow limitation during exercise on ventilatory mechanics, using a motion analysis system that allows researchers to obtain information on chest wall volume changes and chest wall compartmental interactions during high intensity exercise. This motion analysis system is called Optoelectronic Plethysmography (OEP).;Project 1: Optoelectronic Plethysmography (OEP) is a motion analysis tool that can be used to define exercise ventilatory mechanics by analyzing chest wall movements and calculating volume changes. By analyzing breathing mechanics by motion analysis rather than traditional breathing maneuvers, individual components of the chest wall can be analyzed and changes in volume throughout the chest wall can be assessed without altering the individual's natural breathing pattern. This review presents the history and development of OEP technology, along with a summary of the methods used and a discussion of findings to date, giving insight into exercise ventilatory mechanics never investigated before.;Project 2: Differences between the ventilatory mechanics of endurance athletes and non athletes using motion analysis have not yet been described. To determine how increased ventilatory demand impacts ventilatory kinematics, we compared the total chest wall volume variations (VCW) of 18 male and female endurance-trained athletes (ET) to 14 untrained individuals (UT) during exercise. We hypothesized that training and gender would have an effect on VCW and kinematics at maximal exercise. Gender and training significantly influenced chest wall kinematics. Female ET did not change chest wall end-expiratory volume (VCW,ee) or pulmonary ribcage end-expiratory volume (VRCp,ee) with exercise, while female UT significantly decreased VCW,ee and VRCp,ee with exercise (p<0.05). Female ET significantly increased pulmonary ribcage end-inspiratory volume (VRCp,ei) with exercise (p<0.05), while female UT did not change VRCp,ei with exercise. Male ET significantly increased VRCp,ei with exercise (p<0.05); male UT did not. Men and women had significantly different VCW (p<0.05). Women demonstrated the greatest variation of VCW in the pulmonary ribcage compartment (VRCp). Men had similar volumes in the VRCp and the abdomen (VAb). In conclusion, gender and training had a significant association with ventilatory kinematics.;Project 3: The purpose of the last chapter was to investigate the ventilatory mechanics and exercise capacity parameters of female endurance athletes with and without expiratory flow limitation (EFL). Female competitive cyclists participated in two days of testing; day one consisted of a maximal aerobic capacity test ( VO2 max test) with spirometry and day two involved chest wall motion analysis testing during two steady state exercise tests. Baseline flow volume loops were performed prior to exercise and repeated post exercise. During exercise participants performed flow volume loops at minutes 4, 6, 8 and last 30 seconds of exercise. EFL was considered present when the exercise flow volume loop surpassed the baseline flow volume loop. To quantify the degree of flow limitation when comparing the peak exercise flow volume loop to the baseline flow volume loop, we calculated the percent flow volume loop reserve (%FVL reserve). Two levels of submaximal constant-load exercise bouts (at 60% and 85% maximal watts) were employed to investigate if EEFL impacted ventilatory mechanics differently at different intensities. Female endurance athletes demonstrating EFL had normal but significantly different FeV1/FVC ratio and significantly different abdominal ribcage and abdomen percent contribution with increased exercise intensity, but similar exercise capacities compared to the female endurance athletes with no EFL. (Abstract shortened by UMI.).