Is Exercise-Induced Arterial Hypoxemia in Triathletes Dependent on Exercise Modality?

Abstract

To determine whether exercise modality affects arterial hypoxemia (EIAH) during training-intensity exercise, 13 triathletes performed 20 min of cycling (C) followed by 20 min of running (R): C-R, and two weeks later, 20 min of R followed by 20 min of C: R-C. Each trial was performed at an intensity slightly above the ventilatory threshold and close to the daily training intensity (75 % of V·O_2max). Ventilatory data were collected continuously using an automated breath-by-breath system. Partial pressure of oxygen in arterial blood (PaO₂) was measured after each C and R segment and arterial oxyhemoglobin saturation (SpO₂) was monitored continuously via pulse oximetry. The metabolic rate was similar across modalities and trials, i.e., C-R (53.8 ± 3.8 vs. 51.1 ± 5.3 ml · min^-1 · kg^-1) and R-C (52.2 ± 4.5 vs. 53.2 ± 4.6 ml · min^-1 · kg^-1). EIAH showed significantly greater severity for R compared to C irrespective of the order (p < 0.05 for both trials). R values of PaO₂ (and SpO₂) for C-R and R-C were 88.7 ± 6.0 mm Hg (93.0 ± 0.6 % SpO₂) and 86.6 ± 7.3 mm Hg (93.5 ± 0.6 % SpO₂) and C values were 93.7 ± 8.4 mm Hg (95.4 ± 0.4 % SpO₂) and 91.4 ± 5.4 mm Hg (94.8 ± 0.3 % SpO₂). R ventilatory data described a significantly different breathing pattern than C, with higher respiratory rate (35.9 b · min^-1 vs. 51.1 b · min^-1 for C-R, p < 0.01; and 50.0 b · min^-1 vs. 41.5 b · min^-1 for R-C, p < 0.01) and lower tidal volume (2636 ml vs. 2282 ml for C-R, p < 0.02 and 2272 ml vs. 2472 ml for R-C, p < 0.05). We concluded that EIAH was greater during running than cycling for a similar metabolic rate corresponding to training intensity and that EIAH could thus be considered dependent on exercise modality.

Key words

Pulmonary gas exchanges - EIAH - DLCO - endurance training - breathing pattern - triathlon

References

• 1 Beaver W L, Wasserman K, Whipp B J. A new method for detecting anaerobic threshold by gas exchange.  J Appl Physiol. 1986;  60 2020-2027
• 2 Brown D D, Knowlton R G, Sanjabit P B, Szurgot B T. Re-examination of exercise-induced hypoxaemia in highly trained athletes.  Br J Sports Med. 1993;  27 167-170
• 3 Caillaud C, Anselme F, Mercier J, Préfaut C. Pulmonary gas exchange and breathing pattern during and after exercise in highly trained athletes.  Eur J Appl Physiol. 1993;  67 431-437
• 4 Caillaud C, Serre-Cousine O, Anselme F, Capdevilla X, Préfaut C. Computerized tomography and pulmonary diffusing capacity in highly trained athletes after performing a triathlon.  J Appl Physiol. 1995;  79 1226-1232
• 5 Dempsey J A, Hanson P, Hendersen K. Exercise induced arterial hypoxemia in healthy human subjects at sea level.  J Appl Physiol. 1984;  355 161-175
• 6 Dempsey J A, Wagner P D. Exercise-induced arterial hypoxemia.  J Appl Physiol. 1999;  87 1997-2006
• 7 Durand F, Mucci P, Préfaut C. Evidence for an inadequate hyperventilation inducing arterial hypoxemia at submaximal exercise in all highly trained endurance athletes.  Med Sci Sports Exerc. 2000;  32 926-932
• 8 Galy O, Hue O, Boussana A, Le Gallais D, Préfaut C. Cardiorespiratory responses and blood lactate during an experimental run-cycle transition in duathletes.  Int J Sports Med. 2002;  23 162-167
• 9 Galy O, Hue O, Boussana A, Peyreigne C, Mercier J, Prefaut C. Blood rheological responses to running and cycling: a potential effect on the arterial hypoxemia of hughly trained athletes?.  Int J Sports Med. 2005;  26 9-15
• 10 Gavin T, Stager M J. The effect of exercise modality on exercise-induced hypoxemia.  Respir Physiol. 1999;  115 317-323
• 11 Hanel B, Clifford P, Secher N. Restricted postexercise pulmonary diffusion capacity does not impair maximal transport for O₂.  J Appl Physiol. 1994;  77 2408-2412
• 12 Harms C A, Stager J M. Low chemoresponsiveness and inadequate hyperventilation contribute to exercise-induced hypoxemia.  J Appl Physiol. 1995;  79 575-580
• 13 Harms C A, McClaran S R, Nickele G A, Pegelow D F, Nelson W B, Dempsey J A. Effect of exercise-induced arterial O₂ desaturation on V·O_2max in women.  Med Sci Sports Exerc. 2000;  32 1101-1108
• 14 Hill N S, Jacoby C, Farber H W. Effect of an endurance triathlon on pulmonary function.  Med Sci Sports Exerc. 1991;  23 1260-1264
• 15 Holmgreen A, Linderholm H. Oxygen and carbon dioxide tensions of arterial blood during heavy and exhaustive exercise.  Acta Physiol Scand. 1958;  44 203-215
• 16 Holmgreen A, Mc Ilroy M B. Effects of body temperature on arterial blood gas tensions and pH during exercise.  Respir Physiol. 1991;  83 143-154
• 17 Hopkins S R, Barker R C, Brusteart T D, Gavin T P, Entin P, Olfert I M, Veisel S, Wagner P D. Pulmonary gas exchange during exercise in women: effects of exercise type and work increment.  J Appl Physiol. 2000;  89 721-730
• 18 Hue O, Le Gallais D, Chollet D, Boussana A, Préfaut C. Ventilatory responses during experimental cycle-run transition in triathletes.  Med Sci Sports Exerc. 1999;  10 1422-1428
• 19 Hue O, Le Gallais D, Préfaut C. Ventilatory threshold and maximal oxygen uptake in present triathletes.  Can J Appl Physiol. 2000;  25 102-113
• 20 Kreider R B, Boone T, Thompson W R, Burke S, Cortes C W. Cardiovascular and thermal responses of triathlon performance.  Med Sci Sports Exerc. 1988;  20 385-390
• 21 Martin D, Powers S, Cicale M, Collop N, Huang D, Criswell D. Validity of pulse oxymetry during exercise in elite endurance athletes.  J Appl Physiol. 1992;  72 455-458
• 22 Mucci P, Prioux J, Hayot M, Ramonatxo M, Préfaut C. Ventilation response to CO₂ and exercise-induced hypoxemia in master athletes.  Eur J Appl Physiol. 1998;  77 343-351
• 23 Mure M, Domino K B, Lindahl S GE, Hlastala M P, Altemeier W A, Glenny R W. Regional ventilation-perfusion distribution is more uniform in the prone position.  J Appl Physiol. 2000;  88 1076-1083
• 24 Powers S K, Martin D, Dodd S. Exercise-induced hypoxemia in elite endurance athletes. Incidence, causes and impact on V·O_2max.  Sports Med. 1993;  16 14-22
• 25 Préfaut C, Karaouni B, Ramonatxo M, Michel B, Macabiès J. A one-year double-blind follow-up of blood gas tensions and haemodynamics in almitrine bismesylate therapy.  Eur Respir J. 1988;  1 41-50
• 26 Préfaut C, Anselme F, Caillaud C, Masse-Biron J. Exercise-induced hypoxemia in older athletes.  J Appl Physiol. 1994;  76 120-126
• 27 Préfaut C, Durand F, Mucci P, Caillaud C. Exercise-induced hypoxemia in athletes: a review.  Sports Med. 2000;  30 47-61
• 28 Rasmussen J, Hanel B, Diamant B, Secher N H. Muscle mass effect on arterial desaturation after maximal exercise.  Med Sci Sports Exerc. 1991;  23 1349-1352
• 29 Rice A J, Scroop G C, Gore C J, Thornton A T, Chapman M J, Greville H W, Holmes M D, Scicchitano R. Exercise-induced hypoxemia in highly trained cyclists at 40 % peak oxygen uptake.  Eur J Appl Physiol. 1999;  79 353-359
• 30 Rice A J, Scroop G C, Thornton A T, Mc Naughton N S, Rogers K J, Chapman M J, Greville H W, Scicchitano R, Gore C J. Arterial hypoxemia in endurance athletes is greater during running than cycling.  Respir Physiol. 2000;  123 235-246
• 31 Rowell L B, Taylor H L, Wang Y, Carlson W B. Saturation of arterial blood with oxygen during maximal exercise.  J Appl Physiol. 1964;  19 284-286
• 32 Stager J M, Cordain L, Malley J, Wigglesworth J. Arterial desaturation during arm exercise with controlled frequency breathing.  J Swim Res. 1989;  1 5-10
• 33 Younes M, Burrks J. Breathing pattern during and after exercise of different intensities.  J Appl Physiol. 1985;  59 898-908
• 34 Williams J H, Powers S K, Stuart M K. Hemoglobin desaturation in highly trained athletes during heavy exercise.  Med Sci Sports Exerc. 1986;  18 168-173
• 35 Wilkinson L. Systat: The System for Statistics. Evasion, IL; Systat Inc 1990