ISSN:
1439-6327
Keywords:
Key words High-intensity exercise
;
pulmonary diffusing capacity
;
Oxyhemoglobin saturation
;
Athletes
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract The purpose of this investigation was to examine if exercise-induced arterial oxyhemoglobin desaturation selectively observed in highly trained endurance athletes could be related to differences in the pulmonary diffusing capacity (D L) measured during exercise. The D L of 24 male endurance athletes was measured using a 3-s breath-hold carbon monoxide procedure (to give D LCO) at rest as well as during cycling at 60% and 90% of these previously determined ${\dot V}$ O2max. Oxyhemoglobin saturation (S aO2%) was monitored throughout both exercise protocols using an Ohmeda Biox II oximeter. Exercise-induced oxyhemoglobin desaturation (DS) (S aO2% 〈 91% at ${\dot V}$ O2max) was observed in 13 subjects [88.2 (0.6)%] but not in the other 11 nondesaturation subjects [NDS: 92.9 (0.4)%] (P ≤ 0.05), although ${\dot V}$ O2max was not significantly different between the groups [DS: 4.34 (0.65) l / min vs NDS: 4.1 (0.49) l / min]. At rest, no differences in either D LCO [m1 CO · mmHg−1 · min−1: 41.7 (1.7) (DS) vs 41.1 (1.8) (NDS)], D LCO / ${\dot V}$ A [8.2 (0.4) (DS) vs 7.3 (0.9) (NDS)], MVV [l / min: 196.0 (10.4) (DS) vs 182.0 (9.9) (NDS)] or FEV1/FVC [86.3 (2.2) (DS) vs 82.9 (4.7) (NDS)] were found between groups (P ≥ 0.05). However, ${\dot V}$ E / ${\dot V}$ O2 at ${\dot V}$ O2max was lower in the DS group [33.0 (1.1)] compared to the NDS group [36.8 (1.5)] (P ≤ 0.05). Exercise D LCO (m1 CO · mmHg−1 · min−1 ) was not different between groups at either 60% ${\dot V}$ O2max [DS: 55.1 (1.4) vs NDS: 57.2 (2.1)] or at 90% ${\dot V}$ O2max [DS: 61.0 (1.8) vs NDS: 61.4 (2.9)]. A significant relationship (r = 0.698) was calculated to occur between S aO2% and ${\dot V}$ E / ${\dot V}$ O2 during maximal exercise. The present findings indicate that the exercise-induced oxyhemoglobin desaturation seen during submaximal and near-maximal exercise is not related to differences in D L, although during maximal exercise S aO2 may be limited by a relatively lower exercise ventilation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004210050183
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