The High Intensity Interval Training (HIIT) is known for promoving important metabolic responses. The metabolomics has been identified as a highly sensitive method, which allows the identification of large amounts of metabolites that are present in several biological samples. The temporal kinetics of metabolic responses to HIIT is still unclear and there are not comprehensive analysis of these responses after prolonged periods off exercise yet. The aim of this project is to investigate the time course of metabolic responses after an acute session of HIIT through metabolomic analysis. It is expected to identify the greatest moment of expression of the metabolome and the specific moments of the peaks of expression of different metabolites after an acute session of HIIT.