González-Hidalgo G, Sánchez-Flores H, López-Castellanos G

Language: Spanish
References: 9
Page: 487-492
PDF size: 34.03 Kb.

ABSTRACT

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.

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