Non-linear relationship between oxygen uptake and power output in the Astrand nomogram - old data revisited

• Autorzy: Zoladz J.A. , Szkutnik Z. , Majerczak J. , Duda K. , Pedersen P.K.
• Języki publikacji: EN

Abstrakty

EN

For the last decade there have been considerable discussion concerning the linearity / non-linearity of the oxygen uptake (O2) - power output (W) relationship with strong experimental evidence of non-linearity provided mainly by breath-by-breath measurements. In this study, we attempted to answer the question whether the O2 - W relationship in the Åstrand nomogram, as presented in the Textbook of Work Physiology, P.-O. Åstrand et al. (2003), page 281, based on the Douglas bag method, is indeed linear, as stated by the authors before, or if a change point in O2, described by Zoladz et al. (1998) Eur J Appl Physiol 78: 369-377, can possibly be detected in those data. The O2 - W data were taken from the Åstrand nomogram referenced above and from the Table 9.5 on page 282 in the same reference and tested for the presence of the change point in O2, using our two-phase model (see the reference above). In the first phase, a linear O2 - W relationship was assumed, whereas in the second one (above the so-called change point) an additional increase in O2 above the values expected from the linear model was allowed. It was found that in the data taken from the Åstrand nomogram (data for men), as well as in the data taken from the Table 9.5, statistically significant change points in O2 were present at the power output of 150 W. The documentation of the presence of a change point in the O2 - W relationship in the Åstrand data provides further evidence for the existence of a non-linearity in the O2 - W relationship in incremental exercise tests of humans, also in O2 data based upon the Douglas bag method.

Słowa kluczowe

EN

fatique; exercise; oxygen uptake; Astrand nomogram

• Wydawca: -
• Czasopismo: Journal of Physiology and Pharmacology
• Rocznik: 2007
• Tom: 58
• Numer: 2
• Opis fizyczny: p.265-273,fig.,ref.

Twórcy

autor

Zoladz J.A.

• University School of Physical Education, Al.Jana Pawla II 78. 31-571 Krakow, Poland

autor

Szkutnik Z.

autor

Majerczak J.

autor

Duda K.

autor

Pedersen P.K.