To investigate the acute effect of gait retraining aimed at reducing tibial peak positive acceleration (PPA) on energetic cost (VO2).Intervention with a pre/post-test design.University biomechanics laboratory.12 healthy male runners (23.4 ± 5.3 years, 179.7 ± 4.3 cm, 75.6 ± 9.2 kg).Tibial PPA and oxygen consumption (VO2) were measured after a five minute baseline run and at the end of a gait retraining session aimed at minimizing tibial PPA.Tibial PPA significantly decreased between baseline and after gait retraining (32.6%, p = 0.007). VO2 significantly increased between the two time periods (9.3%, p = 0.008). There was no correlation between change in tibial PPA and change in VO2 (p = 0.956, r = 0.018).Practitioners who aim to reduce injury risk by minimizing tibial PPA in runners need to consider the possible acute effect on performance as a result of changes in VO2. Further investigation is warranted to understand the energetic cost of different kinematic strategies used by individuals.