e., climb 2) occurred. Our original hypotheses were that our precooling strategy would result in lower body temperatures compared with the control condition and the prior ingestion of a hyperhydration strategy would be further enhanced with the addition of glycerol. While glycerol hyperhydration resulted in an increased fluid balance of ~330 ml (10%) and the precooling technique EX 527 nmr caused a further small to
moderate reduction in deep body temperature, together these alterations did not lead to a clear improvement in overall performance. In fact, on further inspection of JNK-IN-8 chemical structure performance data, a possible (49% chance) performance benefit (2%) was observed on climb 2 following hyperhydration, without glycerol, plus precooling (PC intervention) over the control trial. This improved performance was associated with subjects reporting a lower perception of effort over the first 10 km of the time trial (2.5 km short of the top of the climb), despite similar pacing strategies and physiological
perturbations (i.e., rectal temperature, heart rate, thermal comfort and stomach fullness) across all trials. AC220 As such, it appears that benefits associated with hyperhydration plus precooling offered some advantage in attenuating the perception of effort during the initial portion of the trial, allowing for improved performance in the later stages of the trial when thermal load was greatest. These results may be partially explained by the pre-trial brief, in which subjects were instructed “if feeling filipin good, to save the big effort for the second lap”. Despite lower core
body temperature and improved thermal comfort as a result of precooling and hyperhydration with the co-ingestion of glycerol, performance was not significantly different to the control trial over any section of the course. Moreover, although subjects received the same precooling intervention, the magnitude of cooling was greater in the PC+G trial compared with the PC trial (a moderate versus small reduction in rectal temperature, respectively). We are unable to provide a clear explanation into the potential mechanism of this enhanced effect.