Oral contraceptives, exercise, and acute mountain sickness in women.
BACKGROUND
Previous research has found that exercise exacerbated acute mountain sickness (AMS) in men.


OBJECTIVE
The current study tested this relationship in women taking oral contraceptives.


METHODS
We studied seven women at 428 mmHg for 10 h; once while at rest (R) and once while performing intermittent exercise (EX).


RESULTS
AMS scores had a slight increase at 9 vs. 0 h at altitude in both trials (p < 0.05). Resting measurements of ventilation (VE), arterial oxygen saturation (SPO2), end tidal O2 (PETO2), and end tidal CO2 (PETCO2) were not different over time or between trials (p > 0.05). While fluid intake did not change, urine output increased during the 0-3 h period, regardless of trial, and returned to baseline values by the 6-9 h period (218 +/- 37 vs. 121 +/- 22 ml x h(-1); p < 0.05). During exercise, SPO2 significantly dropped compared with similar time points in R (73.1 +/- 1.1 vs. 85.7 +/- 1.8%; p < 0.05). Despite exercise-induced desaturation, the AMS scores were not significantly different between R and EX.


CONCLUSIONS
These results suggest that oral contraceptives may cause a compensation for the physiological responses to exercise critical for the development of AMS.
Sandoval
D A
DA
Central Washington University, Department of Physical Education, Health Education, and Leisure Services, Ellensburg, WA, USA. darleen.sandoval@mcmail.vanderbilt.edu
Maes
D P
DP
D'Acquisto
L
L
Icenogle
M
M
Roach
R C
RC
D000328:Adult; D000532:Altitude Sickness / Q000139:chemically induced / Q000503:physiopathology*; D003276:Contraceptives, Oral / Q000009:adverse effects / Q000494:pharmacology*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D010101:Oxygen Consumption / Q000187:drug effects; D012123:Pulmonary Ventilation / Q000502:physiology; D012119:Respiration / Q000187:drug effects; D014556:Urine; D014882:Water-Electrolyte Balance / Q000187:drug effects* / Q000502:physiology
D003276:Contraceptives, Oral