Chapman, R. F., Stager, J. M., Tanner, D. A., Stray-Gundersen, J., & Levine, B. D. (2010). Impairment of 3,000 m racing performance at moderate altitude is influenced by VO2 and SaO2 maintenance. Presentation 1989 at the 2010 Annual Meeting of the American College of Sports Medicine, Baltimore, Maryland; June 2-5.

This study examined if arterial oxyhemoglobin saturation (SaO2) and oxygen uptake (VO2) maintenance during heavy exercise in acute hypoxia are related to the acute decline in racing performance of elite athletes (M = 18; F = 9) at altitude. Ss performed a treadmill exercise bout at a constant speed which simulated their 3,000 m race pace, both in normoxia (elevation 230m) and breathing 16.3 % O2 (simulating 2,100 m). Separate 3,000 m time-trials were completed on 400 m all-weather outdoor tracks at sea-level 18 hours before exposure to altitude, and 48 hours after arrival at altitude (2,100 m).

The average 3,000 m time-trial performance for the group was significantly slower at altitude than at sea-level. Performance declines were similar in men and women. Athletes grouped as low SaO2 during race-pace treadmill running in normoxia (N = 7) had a significantly larger decline in race-pace VO2 in hypoxia and slowing of 3,000 m race time at altitude compared to Ss with high SaO2 during race pace running in normoxia. SaO2 during normoxic race-pace running was moderately correlated with the decline in VO2 from normoxia to hypoxia during race-pace running, and lowly correlated with the decline in 3,000 m race time at altitude.

Implication. The degree of arterial oxyhemoglobin desaturation during heavy exercise, already known to influence the decline in VO2max at altitude, has some probable contribution to the magnitude of the decline in racing performance at moderate altitude.

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