Acute Effect of Passive Hyperthermia on Lactate Concentrations

Abstract

Background: Knowledge on the effect of heat on recovery is still incomplete. The present study aimed to evaluate the effect of a passive acute hyperthermic stimulus before and after a lactic anaerobic test on the production and oxidation of lactate blood concentrations. In addition, the purpose was to evaluate the effect that the application of this previous hyperthermic stimulus may have on the athletic performance in the test. Methods: For this purpose, a cross-over design through an anaerobic treadmill test in three different situations (normothermia, pre-test hyperthermia, and post-test hyperthermia) was performed. Twelve male subjects participated (age: 21.25 ± 1.64 years; height: 1.76 m ± 0.08; weight: 72.59 ± 9.44 kg). An anthropometric assessment was carried out with weight, height, skinfolds, body perimeters and diameters, and external and internal body temperatures in each of the tests. A nutritional survey was also carried out 48 h prior to each test. Results: The results of the study showed a decrease in blood lactate concentrations when the hyperthermic effect was applied as passive recovery just after the end of the test (p < 0.05). A decrease in lactate concentrations was also achieved when applying the hyperthermic effect just before the start of the test (p < 0.05). However, no significant improvements were obtained from this application of heat on test performance. Conclusions: The results suggest that the application of passive acute hyperthermia has a favourable effect in terms of decreasing blood lactate concentrations in a 5 min recovery period after lactic anaerobic activity.