title: Effect of arterial carbon dioxide on ventilation during recovery from impulse exercises of various intensities.
abstract: To determine that whether arterial carbon dioxide (PaCO₂) affects ventilation (VE) during recovery from impulse-like exercises of various intensities, subjects performed four impulse-like tests with different workloads. Each test consisted of a 20-sec impulse-like exercise at 80 rpm and 60-min recovery. Blood samples were collected at rest and during recovery to measure blood ions and gases. VE was measured continuously during rest, exercise and recovery periods. A significant curvilinear relationship was observed between VE and pH during recovery from the 300- and 400-watt tests in all subjects. VE was elevated during recovery from the 100-watt test despite no change in any of the humoral factors. Arterialized carbon dioxide (PaCO₂) kinetics showed fluctuation, being increased at 1 min and decreased at 5 min during recovery, and this fluctuation was more enhanced with increase in exercise intensity. There was a significant relationship between VE and PaCO₂ during recovery from the 300- and 400-watt tests in all subjects. The results of the present study demonstrate that pH and neural factors drive VE during recovery from impulse-like exercise and that fluctuation in PaCO₂ controls VE as a feedback loop and this feedback function is more enhanced as the work intensity increases.
authors.affiliation: Graduate School of Education, Hokkaido University, Sapporo, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Afroundeh
authors.forename: T
authors.initials: T
authors.lastname: Arimitsu
authors.forename: R
authors.initials: R
authors.lastname: Yamanaka
authors.forename: C S
authors.initials: CS
authors.lastname: Lian
authors.forename: T
authors.initials: T
authors.lastname: Yunoki
authors.forename: T
authors.initials: T
authors.lastname: Yano
mesh_terms: D000138:Acidosis / Q000503:physiopathology; D002245:Carbon Dioxide / Q000097:blood*; D002648:Child; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000379:methods; D025461:Feedback, Physiological / Q000502:physiology*; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D010100:Oxygen / Q000097:blood; D010101:Oxygen Consumption / Q000502:physiology*; D011188:Potassium / Q000097:blood; D012123:Pulmonary Ventilation / Q000502:physiology*
chemical_list: D002245:Carbon Dioxide; D019344:Lactic Acid; D011188:Potassium; D010100:Oxygen