the mobilization hypothesis (andzel & gutin, 1976) states that starting a performance with an elevated baseline oxygen consumption will improve performance by reducing the oxygen deficit at the beginning of the task, allowing for greater anaerobic capacity at the end. the purpose of this study was to examine how recovering to different percentages of heart rate reserve (hrr) and oxygen consumption reserve (vo2r) after a warm-up influences running performance in distance runners. two research questions were developed: how does recovering to 50% hrr vs. 35% hrr after a warm-up influence run to exhaustion performance, and do % vo2r and % hrr decrease similarly when recovering to 35% and 50% hrr. sixteen trained middle- and long-distance runners were recruited from the 阿根廷vs墨西哥竞猜 varsity track- and-field team and the lakehead athletics club. testing was completed over three sessions. first session involved treadmill accommodation and vo2max testing. the second and third sessions involved performing a warm-up followed by recovering to either 35% or 50% hrr before completing the performance of running at 105% vvo2max with 1% grade until exhaustion. paired samples t-test found no significant differences in run to exhaustion time [t (15) = -1.016, p = .326] after recovering to either 50% hrr or 35% hrr. one-sample chi-square goodness-of-fit test found values of %vo2r were significantly lower than the expected values for both 35% and 50% hrr recovery trials (p = .000, for both trials). in conclusion, participants may have been too close to baseline measures to facilitate the mobilization hypothesis. alternatively, both trials may have been elevated sufficiently but there was no significant difference between the trials. % hrr and % vo2r were not equal during recovery, but this was likely impacted by the intensity of the stride (15-seconds at 105% vvo2max). further research into the methods used to warm up prior to long-duration performance is recommended.