U Drescher1, J Koschate2, T Schiffer3, S Schneider4, U Hoffmann2. 1. Institute of Physiology and Anatomy, Am Sportpark Müngersdorf 6, German Sport University Cologne, Cologne, 50933, Germany. Electronic address: Drescher@dshs-koeln.de. 2. Institute of Physiology and Anatomy, Am Sportpark Müngersdorf 6, German Sport University Cologne, Cologne, 50933, Germany. 3. Outpatient Clinic for Sports Traumatology and Public Health Consultation, Am Sportpark Müngersdorf 6, German Sport University Cologne, Cologne, 50933, Germany. 4. Institute of Movement and Neurosciences, Am Sportpark Müngersdorf 6, German Sport University Cologne, Cologne, 50933, Germany; Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore, Queensland, 4558, Australia.
Abstract
PURPOSE: The aim of the study was to compare the kinetics responses of heart rate (HR), pulmonary (V˙O2pulm) and predicted muscular (V˙O2musc) oxygen uptake between two different pseudo-random binary sequence (PRBS) work rate (WR) amplitudes both below anaerobic threshold. METHODS: Eight healthy individuals performed two PRBS WR protocols implying changes between 30W and 80W and between 30W and 110W. HR and V˙O2pulm were measured beat-to-beat and breath-by-breath, respectively. V˙O2musc was estimated applying the approach of Hoffmann et al. (Eur J Appl Physiol 113: 1745-1754, 2013) considering a circulatory model for venous return and cross-correlation functions (CCF) for the kinetics analysis. RESULTS: HR and V˙O2musc kinetics seem to be independent of WR intensity (p>0.05). V˙O2pulm kinetics show prominent differences in the lag of the CCF maximum (39±9s; 31±4s; p<0.05). CONCLUSIONS: A mean difference of 14W between the PRBS WR amplitudes impacts venous return significantly, while HR and V˙O2musc kinetics remain unchanged.
PURPOSE: The aim of the study was to compare the kinetics responses of heart rate (HR), pulmonary (V˙O2pulm) and predicted muscular (V˙O2musc) oxygen uptake between two different pseudo-random binary sequence (PRBS) work rate (WR) amplitudes both below anaerobic threshold. METHODS: Eight healthy individuals performed two PRBS WR protocols implying changes between 30W and 80W and between 30W and 110W. HR and V˙O2pulm were measured beat-to-beat and breath-by-breath, respectively. V˙O2musc was estimated applying the approach of Hoffmann et al. (Eur J Appl Physiol 113: 1745-1754, 2013) considering a circulatory model for venous return and cross-correlation functions (CCF) for the kinetics analysis. RESULTS: HR and V˙O2musc kinetics seem to be independent of WR intensity (p>0.05). V˙O2pulm kinetics show prominent differences in the lag of the CCF maximum (39±9s; 31±4s; p<0.05). CONCLUSIONS: A mean difference of 14W between the PRBS WR amplitudes impacts venous return significantly, while HR and V˙O2musc kinetics remain unchanged.