The purpose of the study was to determine whether steady state exercise (SSE) or high intensity
interval exercise (HIIE) would better improve energy expenditure (EE) during 90 minutes of
excess post exercise oxygen consumption (EPOC) while attempting to match EE between both
exercise protocols. We also wanted to examine physiological changes during post exercise
measurements, which included VO2, RER, VE and HR. Twelve males aged between 19 and 24
were assigned to the SSE and HIIE conditions. A VO2max and a 30s-all-out sprint set at 150% of
maximum workload was performed on a cycling ergometer interspersed by 5 minutes to ensure
sufficient recovery time. Participants randomly completed SSE or HIIE followed by 90 minutes
of EPOC. A gross efficiency (GE) of 18% was used in order to best quantify the anaerobic
attributable EE during the HIIE in order to estimate total EE. Our results indicate that the HIIE
expended less EE than SSE and from our pre-test EE estimations (p<0.05). With that being said,
HIIE was able to generate a greater EE during EPOC in comparison to SSE, while utilizing more
grams of fat during post exercise measurements (p<0.05). There was no significant difference
between both protocols when adding exercise and EPOC EE. Physiological markers such as VO2
(L.min-1), VE (L.min-1) and HR were significantly greater in HIIE during EPOC. To conclude,
our findings indicate that HIIE is a time efficient workout able to expend more EE, utilize more
fat and have greater physiological responses during EPOC when compared to SSE.Master of Human Kinetic