Lactate Profile and Fat Oxidation During Exercise

The goal of this clinical trial is to test whether changes in lactate kinetics during exercise (due to glycogen depletion or hyperthermia) alter the pattern of fat oxidation during a maximal incremental cycle ergometer test in healthy young active people. The main questions it aims to answer are:Will a rightward shift in lactate kinetics, induced by a previous glycogen depletion, produce a rightward shift in fat oxidation?Will a leftward shift in lactate kinetics due to an increase in ambient temperature produce a leftward shift in fat oxidation?Participants will perform three maximal incremental tests in three different conditions:one in the control condition;one with glycogen depletion;and one with ambient heat (the latter two in randomized, counterbalanced order).

Inclusion Criteria:Perform endurance training with a volume of between 3 and 12h/weekIn women, having regular menstrual cycles (25-35 days length)In women, being able to perform the test without menstrual discomfort or pain and without having taken anti-inflammatory or analgesic drugsExclusion Criteria:Suffering from any previous disease, disorder or ailment that could affect the results of the study variablesSmokingIn women, using any type of hormonal contraceptiveIn women, having heavy menstrual bleeding, detected with the menstrual bleeding questionnaire proposed by Wyatt et al. (2001)