title: Cardiorespiratory Kinetics Determined by Pseudo-Random Binary Sequences - Comparisons between Walking and Cycling.
abstract: This study aims to compare cardiorespiratory kinetics as a response to a standardised work rate protocol with pseudo-random binary sequences between cycling and walking in young healthy subjects. Muscular and pulmonary oxygen uptake (V̇O2) kinetics as well as heart rate kinetics were expected to be similar for walking and cycling. Cardiac data and V̇O2of 23 healthy young subjects were measured in response to pseudo-random binary sequences. Kinetics were assessed applying time series analysis. Higher maxima of cross-correlation functions between work rate and the respective parameter indicate faster kinetics responses. Muscular V̇O2kinetics were estimated from heart rate and pulmonary V̇O2using a circulatory model. Muscular (walking vs. cycling [mean±SD in arbitrary units]: 0.40±0.08 vs. 0.41±0.08) and pulmonary V̇O2kinetics (0.35±0.06 vs. 0.35±0.06) were not different, although the time courses of the cross-correlation functions of pulmonary V̇O2showed unexpected biphasic responses. Heart rate kinetics (0.50±0.14 vs. 0.40±0.14; P=0.017) was faster for walking. Regarding the biphasic cross-correlation functions of pulmonary V̇O2during walking, the assessment of muscular V̇O2kinetics via pseudo-random binary sequences requires a circulatory model to account for cardio-dynamic distortions. Faster heart rate kinetics for walking should be considered by comparing results from cycle and treadmill ergometry.
authors: Institute of Physiology and Anatomy, German Sport University Cologne, Cologne, Germany.
authors: J
authors: J
authors: Koschate
authors: U
authors: U
authors: Drescher
authors: Institute of Physiology and Anatomy, German Sport University Cologne, Cologne, Germany.
authors: L
authors: L
authors: Thieschäfer
authors: Olympic Training Centre Rheinland, Performance Diagnostic, Cologne, Germany.
authors: O
authors: O
authors: Heine
authors: Institute of Physiology and Anatomy, German Sport University Cologne, Cologne, Germany.
authors: K
authors: K
authors: Baum
authors: Institute of Physiology and Anatomy, German Sport University Cologne, Cologne, Germany.
authors: U
authors: U
authors: Hoffmann
mesh_terms: D000328:Adult; D001642:Bicycling / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006339:Heart Rate; D006801:Humans; D007700:Kinetics; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology*; D016138:Walking / Q000502:physiology*; D055815:Young Adult