Prueba de esfuerzo a 44°C y 80 % de humedad.

Objective: to compare the fatigue in a stress test at high temperature and humidity in eight healthy volunteers. Methods: the time of pedaling in the ergometer cycle was measured to know the exercise's efficiency at 30 km/h until the volunteers presented exhaustion or their heart frequency increased > 160 beating per minute. A basal test in the tunnel's ventilation of the Naica mine at 37.5 °C and 40 % of humidity was done. We repeat the stress test at the entrance of the cave, where temperature was 44 °C and 80 % of humidity. We compared using the protector equipment with ice and cold air breathing suit. Results: the stress test al 44 °C and 80 % of humidity with the protector suit was interrupted al the 75% because of an increase in the heart frequency (> 160 per minute)The exercise time was duplicated in the 62 % and was increased in the 100% on the participants with an average increase of 2.25 times and a rank (1.12-3.3). Statistical Wilcoxon test the differences between the times of stress test with and without equipment alt 44 °C an 80 % of humidity with a Z of 2.52 and a p of .012 was done. [ABSTRACT FROM AUTHOR]