PT - JOURNAL ARTICLE AU - Nicholas Tiller AU - Ian Campbell AU - Lee Romer TI - Mechanical ventilatory constraints of upper- vs. lower-body exercise in healthy adults DP - 2013 Sep 01 TA - European Respiratory Journal PG - 3490 VI - 42 IP - Suppl 57 4099 - http://erj.ersjournals.com/content/42/Suppl_57/3490.short 4100 - http://erj.ersjournals.com/content/42/Suppl_57/3490.full SO - Eur Respir J2013 Sep 01; 42 AB - Introduction: There are unequivocal differences in the cardiorespiratory response to exercise performed with the upper-limbs compared to the lower-limbs, but the mechanical-ventilatory responses to exercise have not been systematically studied. Aim: To assess mechanical-ventilatory and perceptual responses to upper- vs. lower-body exercise in healthy adults. Methods: Breathing pattern, operating lung volumes, oesophageal pressure (Poe) derived measures of respiratory mechanics, and dyspnoea (Borg CR10) were assessed in eight recreationally-active men [24 ± 5 (SD) y] during two maximal graded exercise tests, performed with the upper- or lower-body in a randomised/counterbalanced order on separate days. Exercise tests were repeated at work rates equivalent to 20, 40, 60, 80 and 100% maximum arm ventilation (VEarm). Results: There was a significant increase in respiratory frequency (P < 0.05) and a significant decrease in tidal volume (P < 0.001) with upper- vs. lower-body exercise at all percentages of VEarm (2.0 ± 0.9 vs. 2.6 ± 0.7 L at 100%). The change in tidal volume was due primarily to an upward shift in EELV (P = 0.002 at 100% VEarm) with only limited evidence of expiratory flow limitation. Arm-cranking resulted in greater neuro-mechanical uncoupling at all exercise ventilations as reflected by smaller changes in lung volume in response to a given respiratory motor output (pressure per breath), but dyspnoea was not different between modes. Conclusions: Dynamic hyperinflation and neuro-mechanical uncoupling do not contribute to dyspnoea during upper-body exercise when respiratory motor output is maintained.