title: Mechanomyographic and metabolic responses during continuous cycle ergometry at critical power from the 3-min all-out test.
abstract: There are limited data regarding metabolic responses during continuous exhaustive rides at critical power (CP) from the 3-min all-out test. In addition, no previous studies have examined the mechanomyographic (MMG) responses at CP from the 3-min all-out test. Therefore, this study examined the metabolic and MMG responses during continuous exercise at CP determined from the 3-min all-out test. Nine college-aged females (mean±SD: age 23.0±3.6yrs) performed an incremental test to exhaustion on a cycle ergometer to identify the gas exchange threshold, peak oxygen consumption rate (V˙O2 peak) and heart rate peak (HR peak). The V˙O2, HR, MMG amplitude and mean power frequency (MPF) responses were examined during continuous rides to exhaustion at CP (81±6% peak power). There were significant increases in V˙O2 and HR over time and there was no significant difference between V˙O2 peak and V˙O2 at exhaustion or HR peak and HR at exhaustion. There were, however, no significant changes for MMG amplitude or MPF over time. Therefore, the current findings suggested that the 3-min all-out test overestimated CP and the demarcation between the heavy and severe intensity domains. Specifically, the V˙O2 and HR responses did not reach a steady state and were driven to peak values. Furthermore, the non-significant change in MMG amplitude and MPF were consistent with the responses observed at fatiguing power outputs (i.e., >80% peak power).
authors.affiliation: Department of Nutrition and Health Sciences, University of Nebraska-Lincoln, Lincoln, NE, USA. hbergstrom@unlserve.unl.edu
authors.forename: Haley C
authors.initials: HC
authors.lastname: Bergstrom
authors.forename: Terry J
authors.initials: TJ
authors.lastname: Housh
authors.forename: Jorge M
authors.initials: JM
authors.lastname: Zuniga
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Traylor
authors.forename: Robert W
authors.initials: RW
authors.lastname: Lewis
authors.forename: Clayton L
authors.initials: CL
authors.lastname: Camic
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Schmidt
authors.forename: Glen O
authors.initials: GO
authors.lastname: Johnson
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D016552:Ergometry / Q000379:methods*; D005260:Female; D006801:Humans; D007866:Leg / Q000502:physiology; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D009213:Myography / Q000379:methods*; D010101:Oxygen Consumption / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D055815:Young Adult