title: VO2 response at the onset of heavy exercise is accelerated not by diathermic warming of the thigh muscles but by prior heavy exercise.
abstract: We investigated whether the elevated muscle temperature induced by the first bout influenced the VO2 response during a second-bout of heavy exercise. The control conditions were two consecutive 6-min leg cycling bouts (work rate: Δ50% between LT and VO2max) separated by a 6-min baseline at 20 W (L1-ex to L2-ex). In the experimental conditions prior to the main bout (H2-ex), the diathermic warming to the front thigh was substituted for the first-bout. The VO2 response for the second bout was significantly accelerated compared with the first bout (mean ± SD of the τ by monoexponential fitting: L1-ex: 53.8 ± 11.6, L2-ex: 38.7 ± 7.9 s, P < 0.05). The diathermic warm-up, however, could not accelerate VO2 response for subsequent supra-LT leg exercise (τ for H2-ex: 52.3 ± 7.7 s). It was concluded that the facilitation of [VO2 response during supra-LT exercise after prior heavy exercise does not seem to be caused by increased muscle temperature per se and its related factors.
authors.affiliation: Department of Exercise Science & Physiology, School of Health Sciences, Prefectural University of Hiroshima, Hiroshima, Japan. fukuba@pu-hiroshima.ac.jp
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Fukuba
authors.forename: Yuko
authors.initials: Y
authors.lastname: Shinhara
authors.forename: Toshiko
authors.initials: T
authors.lastname: Houman
authors.forename: Masako Yamaoka
authors.initials: MY
authors.lastname: Endo
authors.forename: Masako
authors.initials: M
authors.lastname: Yamada
authors.forename: Akira
authors.initials: A
authors.lastname: Miura
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Hayashi
authors.forename: Hironori
authors.initials: H
authors.lastname: Sato
authors.forename: Shunsaku
authors.initials: S
authors.lastname: Koga
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Yoshida
mesh_terms: D000328:Adult; D003972:Diathermy / Q000379:methods*; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D045268:Flowmeters; D006801:Humans; D018482:Muscle, Skeletal / Q000502:physiology*; D010101:Oxygen Consumption / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology; D011659:Pulmonary Gas Exchange / Q000502:physiology; D019265:Spectroscopy, Near-Infrared; D013848:Thigh / Q000502:physiology*; D055815:Young Adult