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Respiratory indices by gas analysis and fat metabolism by indirect calorimetry in normal subjects and triathletes.

Steding Ehrenborg, Katarina LU ; Buhre, Torsten LU ; Arheden, Håkan LU and Wohlfart, Björn LU (2010) In Clinical Physiology and Functional Imaging 30. p.146-151
Abstract
Summary Background: The effects of exercise on different indices reflecting the metabolism have been of interest for a long time, and a relationship between anaerobic indices and maximal oxygen uptake has been established. The inter-relationship between different respiratory indices during an exercise test remains to be studied in order to understand differences between individuals. Therefore, the aim of this study was to determine three respiratory indices and investigate their inter-relationship in individuals with highly variable working capacity. A second aim was to investigate the fat metabolism at the VO(2) corresponding to the respiratory compensation point (Pq) in the different subjects using indirect calorimetry. Methods: Sixty... (More)
Summary Background: The effects of exercise on different indices reflecting the metabolism have been of interest for a long time, and a relationship between anaerobic indices and maximal oxygen uptake has been established. The inter-relationship between different respiratory indices during an exercise test remains to be studied in order to understand differences between individuals. Therefore, the aim of this study was to determine three respiratory indices and investigate their inter-relationship in individuals with highly variable working capacity. A second aim was to investigate the fat metabolism at the VO(2) corresponding to the respiratory compensation point (Pq) in the different subjects using indirect calorimetry. Methods: Sixty control subjects (20 female) and 18 triathletes (six female) performed an exercise test with gas analysis. Three respiratory indices, derivative crossing (Dx), point of crossing (Px) and respiratory compensation point (Pq), were calculated using a computerized method. Fat metabolism at Pq was calculated using indirect calorimetry. Results: Two different sequences of the respiratory indices were found: Dx<Px<Pq and Dx<Pq<Px. In subjects whom Px occurred before Pq, no fat metabolism was seen at Pq, whilst in subjects with Pq occurring before Px, a combined aerobic fat metabolism and anaerobic carbohydrate metabolism was found at Pq. Conclusion: This study has shown two different sequences of the respiratory indices Dx, Px and Pq in subjects of varying working capacity. The individual differences in the order of occurrence of Px and Pq during the exercise test are most likely caused by different abilities to metabolize fat at high workloads. (Less)
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author
; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Clinical Physiology and Functional Imaging
volume
30
pages
146 - 151
publisher
John Wiley & Sons Inc.
external identifiers
  • wos:000274438800010
  • pmid:20095977
  • scopus:76949101429
  • pmid:20095977
ISSN
1475-0961
DOI
10.1111/j.1475-097X.2009.00918.x
language
English
LU publication?
yes
id
75ac4ae7-dcd1-4ed0-9b8f-5dce16414275 (old id 1540658)
alternative location
http://www.ncbi.nlm.nih.gov/pubmed/20095977?dopt=Abstract
date added to LUP
2016-04-04 07:53:07
date last changed
2022-01-29 02:43:37
@article{75ac4ae7-dcd1-4ed0-9b8f-5dce16414275,
  abstract     = {{Summary Background: The effects of exercise on different indices reflecting the metabolism have been of interest for a long time, and a relationship between anaerobic indices and maximal oxygen uptake has been established. The inter-relationship between different respiratory indices during an exercise test remains to be studied in order to understand differences between individuals. Therefore, the aim of this study was to determine three respiratory indices and investigate their inter-relationship in individuals with highly variable working capacity. A second aim was to investigate the fat metabolism at the VO(2) corresponding to the respiratory compensation point (Pq) in the different subjects using indirect calorimetry. Methods: Sixty control subjects (20 female) and 18 triathletes (six female) performed an exercise test with gas analysis. Three respiratory indices, derivative crossing (Dx), point of crossing (Px) and respiratory compensation point (Pq), were calculated using a computerized method. Fat metabolism at Pq was calculated using indirect calorimetry. Results: Two different sequences of the respiratory indices were found: Dx&lt;Px&lt;Pq and Dx&lt;Pq&lt;Px. In subjects whom Px occurred before Pq, no fat metabolism was seen at Pq, whilst in subjects with Pq occurring before Px, a combined aerobic fat metabolism and anaerobic carbohydrate metabolism was found at Pq. Conclusion: This study has shown two different sequences of the respiratory indices Dx, Px and Pq in subjects of varying working capacity. The individual differences in the order of occurrence of Px and Pq during the exercise test are most likely caused by different abilities to metabolize fat at high workloads.}},
  author       = {{Steding Ehrenborg, Katarina and Buhre, Torsten and Arheden, Håkan and Wohlfart, Björn}},
  issn         = {{1475-0961}},
  language     = {{eng}},
  pages        = {{146--151}},
  publisher    = {{John Wiley & Sons Inc.}},
  series       = {{Clinical Physiology and Functional Imaging}},
  title        = {{Respiratory indices by gas analysis and fat metabolism by indirect calorimetry in normal subjects and triathletes.}},
  url          = {{http://dx.doi.org/10.1111/j.1475-097X.2009.00918.x}},
  doi          = {{10.1111/j.1475-097X.2009.00918.x}},
  volume       = {{30}},
  year         = {{2010}},
}