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Maximal cardiorespiratory responses to one- and two-legged cycling during acute and long-term exposure to 4300 meters altitude

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During exposure to altitudes greater than about 2200 m, maximal oxygen uptake (\(\dot V_{O_{2max} } \)) is immediately diminished in proportion to the reduction in the partial pressure of oxygen in the inspired air. If the exposure lasts longer than a couple of days, an increase in arterial oxygen content (CaO2), due to a hemoconcentration and an increase in arterial oxygen saturation, occurs. However, there is also a reduction in maximal cardiac output (\(\dot Q_{\max }\)) at altitude which offsets the increase in CaO2 and, therefore,\(\dot V_{O_{2max} } \) does not improve. The purpose of this investigation was to study the contribution of the increase in CaO2 to the working muscles without the potentially confounding problem of a reduced\(\dot Q_{\max }\). The approach used was to have seven male subjects (aged 17 to 24 years) perform one- and two-legged\(\dot V_{O_{2max} } \) tests on a cycle ergometer at sea level (SL, PIO2 = 159 Torr), after 1 h at 4300 m simulated altitude (SA, PIO2 = 94 Torr) and during two weeks of residence on the summit of Pikes Peak, CO. (pP, 4300 m, PIO2 = 94 Torr). Cardiac output limits maximal performance during two-legged cycling but does not limit performance during one-legged cycling. During the study, CaO2 changed from 189±3 (mean ±SE) at SL to 161±4 ml·L−1 during SA (SL vs. SA,p<0.01) and to 200±6 ml·L−1 at PP (SL vs. PP,p<0.05; SA vs. PP,p<0.01). Two-legged\(\dot V_{O_{2max} } \) decreased from 3.64±0.26 L·min−1 at SL to 2.70±0.14 L·min−1 during SA (p<0.01) to 2.86±0.16 L·min−1 at PP (p<0.01). One-legged\(\dot V_{O_{2max} } \) decreased from 2.95±0.22 at SL to 2.25±0.17 L·min−1 during SA (SL vs. SA,p<0.01) but improved to 2.66±0.18 L·min−1 at PP (SA vs. PP,p<0.05). Since only one-legged\(\dot V_{O_{2max} } \) increased as more oxygen was made available to the working muscles, the altitude-induced reduction in\(\dot Q_{\max }\) can be implicated as being responsible for the reduction in\(\dot V_{O_{2max} } \) during two-legged cycling.

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  1. Alexander JK, Hartley CH, Modelski M, Grover RF (1967) Reduction of stroke volume during exercise in man following ascent to 3100 m altitude. J Appl Physiol 23:849–858

  2. Astrand PO, Rodahl K (1986) Textbook of work physiology. McGraw-Hill, New York

  3. Buskirk ER (1969) Decrease in physical working capacity at high altitude. In: Hegnauer AH (ed) Biomedicine problems of high terrestrial elevations. US Army Research Institute of Environmental Medicine, Natick, MA 204–222

  4. Davies CTM, Sargeant AJ (1974) Physiological responses to one and two-leg exercise breathing air and 45% oxygen. J Appl Physiol 36:142–148

  5. Davies CTM, Sargeant AJ (1975) Effects of training on the physiological responses to one-and two-legged work. J Appl Physiol 38:377–381

  6. Dill DB, Costill DL (1974) Calculation of percent changes in volumes of blood, plasma and red blood cells in dehydration. J Appl Physiol 247–248

  7. Ekblom B, Huot R, Stein EM, Throstensson AT (1975) Effects of changes in arterial oxygen content on circulation and physical performance. J Appl Physiol 39:71–75

  8. Gleser MA (1973) Effects of hypoxia and physical training on hemodynamic adjustments to one-legged exercise. J Appl Physiol 34:655–659

  9. Grover RF, Reeves JT, Maher JT, McCullough RE, Cruz JC, Denniston JC, Cymerman A (1976) Maintained stroke volume but impaired arterial oxygenation in man at high altitude with supplemental CO2. Circ Res 38:391–396

  10. Grover RF, Weil JV, Reeves JT (1986) Cardiovascular adaptation to exercise at high altitude. In: Pandolf KB (ed) Exercise and sport sciences reviews. Macmillan, New York, pp 269–302

  11. Hartley LH, Vogel JA, Cruz JC (1974) Reduction of maximal exercise heart rate at altitude and its reversal with atropine. J Appl Physiol 36:362–365

  12. Jung RG, Dill DB, Horton R, Horvath SM (1971) Effects of age on plasma aldosterone levels and hemoconcentration at altitude. J Appl Physiol 31:593–597

  13. Klausen K (1966) Cardiac output in man in rest and work during and after acclimatization to 3800 m. J Appl Physiol 21:608–616

  14. Neary PJ, Wenger HA (1986) The effects of one- and two- legged exercise on the lactate and ventilatory threshold. Eur J Appl Physiol 54:591–595

  15. Reeves JT, Groves BM, Sutton JR, Wagner PD, Cymerman A, Malconian MK, Rock PB, Young PM, Houston CS (1987) Operation Everest II: Preservation of cardiac function at extreme altitude J Appl Physiol 63:531–539

  16. Saltin B, Grover RF, Blomqvist CG, Hartley LH, Johnson RL (1968) Maximal oxygen uptake and cardiac output after 2 weeks at 4300 m. J Appl Physiol 25:400–409

  17. Stamford BA, Weltman A, Fulco C (1978) Anaerobic threshold and cardiovascular responses during one- versus two- legged cycling. Res Quart. 49:351–362

  18. Stenberg J, Ekblom B, Messin R (1966) Hemodynamic response to work at simulated altitude 4000 m. J Appl Physiol 21:1589–1594

  19. Sutton JR, Jones NL (1983) Exercise at altitude. Ann Rev Physiol 45:427–437

  20. Sutton JR, Reeves JT, Wagner PD, Groves BM, Cymerman A, Malconian MK, Rock PB, Young PM, Walter SD, Houston CS (1988) Oxygen transport during exercise at extreme simulated altitude: “Operation Everest II”. J Appl Physiol 64:1309–1321

  21. Vogel JA, Gleser M (1972) Effect of carbon monoxide on oxygen transport during exercise. J Appl Physiol 32:234–239

  22. Vogel JA, Hansen JE, Harris CW (1967) Cardiovascular responses in man during exhaustive work at sea level and high altitude. J Appl Physiol 23:531–539

  23. Vogel JA, Hartley H, Cruz JC, Hogen RP (1974) Cardiac output during exercise in sea level residents at sea level and high altitude. J Appl Physiol 36:169–172

  24. Wagner PD, Reeves JT, Sutton JR, Cymerman A, Groves BM, Malconian MK, Young PM (1986) Possible limitation of maximal O2 uptake by peripheral tissue diffusion. (Abstr) Am Rev Respir Dis 133:A202

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Correspondence to Charles S. Fulco.

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Fulco, C.S., Rock, P.B., Trad, L. et al. Maximal cardiorespiratory responses to one- and two-legged cycling during acute and long-term exposure to 4300 meters altitude. Europ. J. Appl. Physiol. 57, 761–766 (1988). https://doi.org/10.1007/BF01076000

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Key words

  • One-legged cycling
  • Altitude acclimatization
  • Cardiac output
  • Maximal oxygen consumption