Advertisement

The influence of inspired oxygen on the oxygen uptake response to ramp exercise

  • Michael L. Walsh
  • Eric W. Banister
Original Article

Abstract

The relation between\(\dot VO_2 \) and work rate (WR) was examined in seven male subjects who performed ramp (1 W·3 s−1) two-legged cycle ergometry to exhaustion while inspiring either hypoxic (12% O2), normoxic (21% O2), or hyperoxic (40% O2) air. The anaerobic threshold was estimated from respiratory gas exchange data and is thus referred to as the respiratory gas exchange threshold (RGET). Prior to the RGET, the\(\Delta \dot VO_2 /\Delta WR\) was greater under normoxic [mean (SD); 10. 19(1.04) ml O2·min−1·W−1] and hyperoxic [10.44 (0.72)] conditions compared with hypoxia [9.34 (0.89)]. Above the RGET, the\(\Delta \dot VO_2 /\Delta WR\) for hypoxia [8.91 (0.63)], normoxia [10.40 (0.77)], and hyperoxia [11.08 (0.48)] were all significantly different from each other. These data indicated that for two-legged, cycle, ramp ergometry in normoxia below the RGET, both the\(\Delta \dot VO_2 /\Delta WR\) and response time was constant. Above the RGET, the normoxic\(\dot VO_2 \) response was the net result of a declining\(\Delta \dot VO_2 /\Delta WR\) and a longer response time to the unsteady state character of a ramp exercise protocol.

Key words

Oxygen uptake kinetics Exercise Hypoxia Hyperoxia Efficiency 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Beaver WL, Wasserman K, Whipp BJ (1986) A new method for detecting anaerobic threshold by gas exchange. J Appl Physiol 60:2020–2027Google Scholar
  2. Hansen JE, Casaburi R, Cooper DM, Wasserman K (1988) Oxygen uptake as related to work rate increment during cycle ergometer exercise. Eur J Appl Physiol 57:140–145Google Scholar
  3. Hughson RL (1990) Exploring cardiorespiratory control mechanisms through gas exchange dynamics. Med Sci Sports Exerc 22:72–79Google Scholar
  4. Koike A, Weiler-Ravell D, McKenzie DK, Zanconato S, Wasserman K (1990) Evidence that the metabolic acidosis threshold is the anaerobic threshold. J Appl Physiol 68:2521–2526Google Scholar
  5. Linnarsson D (1974) Dynamics of pulmonary gas exchange and heart rate changes at start and end of exercise. Acta Physiol Scand [Suppl] 415:1–68Google Scholar
  6. Linnarsson D, Karlsson J, Fagraeus L, Saltin B (1974) Muscle metabolites and oxygen deficit with exercise in hypoxia and hyperoxia. J Appl Physiol 36:399–402Google Scholar
  7. Murphy PC, Cuervo LA, Hughson RE (1989) A study of cardiorespiratory dynamics with step and ramp exercise tests in normoxia and hypoxia. Cardiovase Res 23:825–832Google Scholar
  8. Veith E (1989) Fitting piecewise linear regression functions to biological responses. J Appl Physiol 67:390–396Google Scholar
  9. Walsh ML (1992) Possible mechanisms of oxygen uptake kinetics. Ann Physiol Anthropol 11:215–223Google Scholar
  10. Walsh ML (1993) Oxygen uptake kinetics during exercise. Ph.D. thesis, Simon Fraser University, Burnaby CanadaGoogle Scholar
  11. Walsh ML, Banister EW (1988) Possible mechanisms of the anaerobic threshold: a review. Sports Med 5:269–302Google Scholar
  12. Wasserman K, Koike A (1992) Is the anaerobic threshold truly anaerobic? Chest 101:21IS-218SGoogle Scholar
  13. Wasserman K, Hansen JE, Sue DY, Whipp BJ (1987) Principles of exercise testing and interpretation. Lea and Febiger, PhiladelphiaGoogle Scholar
  14. Whipp BJ, Mahler M (1980) Dynamics of pulmonary gas exchange during exercise. In: West JB (ed) Pulmonary gas exchange, vol 2. Academic Press, New York, pp 33–96Google Scholar
  15. Whipp BJ, Wasserman K (1972) Oxygen uptake kinetics for various intensities of constant-load work. J Appl Physiol 33:351–356Google Scholar
  16. Yoshida T, Chida M, Ichioka M, Makiguchi K, Suda Y (1987) Effect of hypoxia on lactate variables during exercise. J Hum Ergol 16:157–161Google Scholar

Copyright information

© Springer-Verlag 1995

Authors and Affiliations

  • Michael L. Walsh
    • 1
  • Eric W. Banister
    • 1
  1. 1.School of KinesiologySimon Fraser UniversityBurnabyCanada

Personalised recommendations