Exercise and heat orthostatism and the effect of heat acclimation and physical fitness
Shvartz, E.; Meroz, A.; Magazanik, A.; Shoenfeld, Y.; Shapiro, Y.
Aviation Space and Environmental Medicine 48(9): 836-842
1977
ISSN/ISBN: 0095-6562 PMID: 907595 Document Number: 115478
Trained of heat acclimation. The number of fainters in the orthostatic tests administered before exercise, after exercise at 40 W and 80 W, and after exercise in heat, were 3, 4, 6 and 13, respectively. There were no fainting episodes after the .ovrhdot.VO2 max tests. Orthostatic responses in the different conditions were partially related. The trained subjects showed substantially better responses than the untrained ones (10% vs. 25% of fainting episodes), and heat acclimation resulted in marked improvement in orthostatism (decrease to 5% faintings). The results show that .ovrhdot.VO2 max and heat tolerance account for most of the variability which determines orthostatic tolerance.