title: The Effect of Inspiratory Muscle Training on Respiratory and Limb Locomotor Muscle Deoxygenation During Exercise with Resistive Inspiratory Loading.
abstract: We investigated how inspiratory muscle training impacted respiratory and locomotor muscle deoxygenation during submaximal exercise with resistive inspiratory loading. 16 male cyclists completed 6 weeks of either true (n=8) or sham (n=8) inspiratory muscle training. Pre- and post-training, subjects completed 3, 6-min experimental trials performed at ~80%  ˙VO2peak with interventions of either moderate inspiratory loading, heavy inspiratory loading, or maximal exercise imposed in the final 3 min. Locomotor and respiratory muscle oxy-, deoxy-, and total-haemoglobin and myoglobin concentration was continuously monitored using near-infrared spectroscopy. Locomotor muscle deoxygenation changes from 80%  ˙VO2peak to heavy inspiratory loading were significantly reduced pre- to post-training from 4.3±5.6 µM to 2.7±4.7 µM. Respiratory muscle deoxygenation was also significantly reduced during the heavy inspiratory loading trial (4.6±3.5 µM to 1.9±1.5 µM) post-training. There was no significant difference in oxy-, deoxy-, or total-haemoglobin and myoglobin during any of the other loading trials, from pre- to post-training, in either group. After inspiratory muscle training, highly-trained cyclists exhibited decreased locomotor and respiratory muscle deoxygenation during exercise with heavy inspiratory loading. These data suggest that inspiratory muscle training reduces oxygen extraction by the active respiratory and limb muscles, which may reflect changes in respiratory and locomotor muscle oxygen delivery.
authors.affiliation: Center for Sport and Exercise Science, Sheffield Hallam University, Sheffield, United Kingdom of Great Britain and Northern Ireland.
authors.forename: L A
authors.initials: LA
authors.lastname: Turner
authors.affiliation: Department of Kinesiology, St. Ambrose University, Davenport, United States.
authors.forename: S L
authors.initials: SL
authors.lastname: Tecklenburg-Lund
authors.affiliation: Kinesiology, Indiana University, Bloomington, United States.
authors.forename: R
authors.initials: R
authors.lastname: Chapman
authors.affiliation: Department of Kinesiology, Indiana University, Bloomington, United States.
authors.forename: R-J
authors.initials: RJ
authors.lastname: Shei
authors.affiliation: Department of Kinesiology, Indiana University, Bloomington, United States.
authors.forename: D P
authors.initials: DP
authors.lastname: Wilhite
authors.affiliation: Kinesiology, Indiana University, Bloomington, United States.
authors.forename: T
authors.initials: T
authors.lastname: Mickleborough
mesh_terms: D000328:Adult; D001642:Bicycling / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D006801:Humans; D001239:Inhalation; D008297:Male; D010100:Oxygen / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology*; D012129:Respiratory Function Tests; D012132:Respiratory Muscles / Q000502:physiology*; D013848:Thigh / Q000502:physiology*; D055815:Young Adult
chemical_list: D010100:Oxygen