title: The effect of exercise training with an additional inspiratory load on inspiratory muscle fatigue and time-trial performance.
abstract: The purpose was to determine the effect of moderate-intensity exercise training (ET) on inspiratory muscle fatigue (IMF) and if an additional inspiratory load during ET (ET+IL) would further improve inspiratory muscle strength, IMF, and time-trial performance. 15 subjects were randomly divided to ET (n=8) and ET+IL groups (n=7). All subjects completed six weeks of exercise training three days/week at ∼70%V̇O2peak for 30min. The ET+IL group breathed through an inspiratory muscle trainer (15% PImax) during exercise. 5-mile, and 30-min time-trials were performed pre-training, weeks three and six. Inspiratory muscle strength increased (p<0.05) for both groups to a similar (p>0.05) extent. ET and ET+IL groups improved (p<0.05) 5-mile time-trial performance (∼10% and ∼18%) and the ET+IL group was significantly faster than ET at week 6. ET and ET+IL groups experienced less (p<0.05) IMF compared to pre-training following the 5-mile time-trial. In conclusion, these data suggest ET leads to less IMF, ET+IL improves inspiratory muscle strength and IMF, but not different than ET alone.
authors.affiliation: Department of Kinesiology, Kansas State University, Manhattan, KS, USA.
authors.forename: Serina J
authors.initials: SJ
authors.lastname: McEntire
authors.affiliation: Department of Kinesiology, Kansas State University, Manhattan, KS, USA. Electronic address: smith424@ksu.edu.
authors.forename: Joshua R
authors.initials: JR
authors.lastname: Smith
authors.affiliation: Department of Kinesiology, Kansas State University, Manhattan, KS, USA.
authors.forename: Christine S
authors.initials: CS
authors.lastname: Ferguson
authors.affiliation: Department of Kinesiology, Kansas State University, Manhattan, KS, USA.
authors.forename: Kelly R
authors.initials: KR
authors.lastname: Brown
authors.affiliation: Department of Kinesiology, Kansas State University, Manhattan, KS, USA.
authors.forename: Stephanie P
authors.initials: SP
authors.lastname: Kurti
authors.affiliation: Department of Kinesiology, Kansas State University, Manhattan, KS, USA.
authors.forename: Craig A
authors.initials: CA
authors.lastname: Harms
mesh_terms: D000328:Adult; D001642:Bicycling / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D001239:Inhalation / Q000502:physiology*; D008297:Male; D018763:Muscle Fatigue / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology; D012129:Respiratory Function Tests; D012132:Respiratory Muscles / Q000502:physiology*; D055815:Young Adult
keywords: Exercise training; Inspiratory load; Inspiratory muscle fatigue; Respiratory muscle strength; Time-trial performance