No Cover Image

Journal article 1544 views 329 downloads

Aerobic Function and Muscle Deoxygenation Dynamics during Ramp Exercise in Children

Melitta McNarry Orcid Logo, COLIN FARR, ANDREW MIDDLEBROOKE, DEBORAH WELFORD, BRYNMOR BREESE, NEIL ARMSTRONG, ALAN R. BARKER

Medicine & Science in Sports & Exercise, Volume: 47, Issue: 9, Pages: 1877 - 1884

Swansea University Author: Melitta McNarry Orcid Logo

Check full text

DOI (Published version): 10.1249/MSS.0000000000000609

Abstract

PURPOSE:To characterise changes in deoxyhemoglobin ([HHb]) response dynamics in boys and girls during ramp incremental exercise to investigate whether the reduced peak oxygen uptake (peakV˙O2) in girls is associated with a poorer matching of muscle O2 delivery to muscle O2 utilisation, as evidenced...

Full description

Published in: Medicine & Science in Sports & Exercise
ISSN: 0195-9131
Published: 2015
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa21415
Tags: Add Tag
No Tags, Be the first to tag this record!
Abstract: PURPOSE:To characterise changes in deoxyhemoglobin ([HHb]) response dynamics in boys and girls during ramp incremental exercise to investigate whether the reduced peak oxygen uptake (peakV˙O2) in girls is associated with a poorer matching of muscle O2 delivery to muscle O2 utilisation, as evidenced by a more rapid increase in [HHb].METHODS:52 children (31 boys, 9.9 ± 0.6 years, 1.38 ± 0.07 m, 31.70 ± 5.78 kg) completed ramp incremental exercise on a cycle ergometer during which pulmonary gas exchange and muscle oxygenation parameters were measured.RESULTS:When muscle [HHb] was expressed against absolute work rate and V˙O2, girls had an earlier change in [HHb] as evidenced by the lower c/d parameter (Girls: 54 ± 20 W vs Boys: 67 ± 19 W, P=0.023; Girls: 0.82 ± 0.28 L·min vs. Boys: 0.95 ± 0.19 L·min, P=0.055) and plateau (Girls: 85 ± 12 W vs. Boys: 99 ± 18 W, P=0.031; Girls: 1.02 ± 0.25 L·min vs. Boys: 1.22 ± 0.28 L·min, P=0.014). However, when expressed against relative work-rate or V˙O2, there were no sex differences in [HHb] response dynamics (all P>0.20). Significant correlations were observed between absolute and fat-free mass normalised peak V˙O2 and the HHb c/d and plateau parameters when expressed against absolute work-rate or V˙O2. Furthermore, when entered into a multiple regression model, the [HHb] plateau against absolute V˙O2 contributed 12% of the variance in peak V˙O2 after adjusting for fat-free mass, gas exchange threshold, and body fatness (model R =0.81, P<0.001).CONCLUSION:The sex-difference in peak V˙O2 in 9-10 year old children is, in part, related to sex-specific changes in muscle O2 extraction dynamics during incremental exercise.
Keywords: NIRS; O2 delivery; O2 utilization; peak V O2; pre-pubertal; sex
College: Faculty of Science and Engineering
Issue: 9
Start Page: 1877
End Page: 1884

Similar Items