AUTHOR=Eskandari Arezoo , Fashi Mohamad , Saeidi Ayoub , Boullosa Daniel , Laher Ismail , Ben Abderrahman Abderraouf , Jabbour Gerorges , Zouhal Hassane 

TITLE=Resistance Exercise in a Hot Environment Alters Serum Markers in Untrained Males

JOURNAL=Frontiers in Physiology

VOLUME=Volume 11 - 2020

YEAR=2020

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2020.00597

DOI=10.3389/fphys.2020.00597

ISSN=1664-042X

ABSTRACT=Purpose We examined the effects of moderate resistance exercise (RE) on serum cortisol, testosterone, extracellular heat shock protein (HSP70), interleukin (IL)-6 and IL-15 concentrations in untrained males in a hot environment. 
Methods Ten untrained young males (26 ± 3 years; 75.8 ± 6 kg; 177.4±5.3 cm) performed two series of full body RE (3 sets of 8 to 10 repetitions, 30-60 s recovery between series with 70% of one maximal repetition (1-RM), with a rest period of 1 to 3 min between exercises) performed in a random order in both heated (~35ºC) and thermoneutral (22ºC) conditions. Serum concentrations of testosterone, cortisol, HSP70, IL-6 and IL-15 were measured before, at the end, and 1-h after RE sessions. Participants in both groups consumed 4 ml of water/kg body mass every 15 min.
Results There were time-related changes in testosterone, HSP70, IL-6 (P<0.001); and cortisol and IL-15 (P<0.05). Levels of cortisol, HSP70, and IL-6 increased immediately for RE at 35ºC, and testosterone and IL-15 levels were decreased. Changes in serum testosterone, HSP70, cortisol, IL-15 and IL-6 levels were reversed after 1-h. A significant time × condition interaction was observed for IL-15, HSP70 (P<0.001); cortisol and IL-6 (P<0.05), but not for testosterone (P>0.05). 
Conclusion RE in a heated environment may not be appropriate for achieving muscle adaptations due to acute changes of hormonal and inflammatory markers.