title: Comparison of cardiovascular responses between upright and recumbent cycle ergometers in healthy young volunteers performing low-intensity exercise: assessment of reliability of the oxygen uptake calculated by using the ACSM metabolic equation.
abstract: OBJECTIVE
  To clarify (1) differences in cardiovascular response during low-intensity exercise in the upright versus the recumbent position, and (2) whether the oxygen uptake (V o 2 ) calculated by the American College of Sports Medicine (ACSM) metabolic equation reflects the actual V o 2 at low-intensity testing.
  
  
  METHODS
  Repeated-measures comparison study.
  
  
  METHODS
  University research laboratory.
  
  
  METHODS
  Thirty-one healthy, young volunteers (age, 23+/-2y).
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Blood pressure, rate pressure product (RPP), V o 2 , oxygen pulse, carbon dioxide output (V co 2 ), and ventilatory equivalent (V e ) were measured during graded exercise testing using upright and recumbent cycle ergometers. The estimated V o 2 was calculated by using the ACSM metabolic equation.
  
  
  RESULTS
  Systolic blood pressure, RPP, V o 2 , oxygen pulse, V co 2 , and V e at 15 or 30W were significantly higher in the recumbent position than in the upright one ( P <.05), however, no significant differences were observed at 50 and 70W. The estimated V o 2 during exercise was significantly higher than the actual one, at every level of intensity, from 15 to 70W ( P <.05).
  
  
  CONCLUSIONS
  Cardiovascular responses should be carefully monitored even during low-intensity exercise using a recumbent cycle ergometer. The V o 2 estimated using the ACSM metabolic equation did not reflect the actual V o 2 during low-intensity exercise at 70W or less.
authors.affiliation: Department of Angiology and Cardiology, Graduate School of Medical Sciences, Kanagawa, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Saitoh
authors.forename: Atsuhiko
authors.initials: A
authors.lastname: Matsunaga
authors.forename: Kentaro
authors.initials: K
authors.lastname: Kamiya
authors.forename: Misao N
authors.initials: MN
authors.lastname: Ogura
authors.forename: Junko
authors.initials: J
authors.lastname: Sakamoto
authors.forename: Ryusuke
authors.initials: R
authors.lastname: Yonezawa
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kasahara
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Watanabe
authors.forename: Takashi
authors.initials: T
authors.lastname: Masuda
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001794:Blood Pressure / Q000502:physiology; D002245:Carbon Dioxide / Q000378:metabolism; D002320:Cardiovascular Physiological Phenomena; D016552:Ergometry / Q000295:instrumentation*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology*
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen