© 2020 The Authors Using a pre-post design, we investigated state anxiety and worry responses to a single Wingate, three weeks of sprint interval training (SIT), and, change in response to a single Wingate. Differences between males with and without elevated worry were explored. Thirty-eight young adult males, 18 with elevated worry (Penn State Worry Questionnaire [PSWQ] ¿45), completed a single 30s Wingate at 7.5% body mass before and after three weeks of SIT (nine sessions of 4¿6 sprints). The state subscale of the State-Trait Anxiety Inventory assessed state anxiety; the PSWQ measured worry and worry engagement. A single Wingate increased state anxiety (d = -0.37, [-0.82, 0.09]) and decreased worry engagement (d = 0.16, [-0.29, 0.61]). SIT resulted in non-significant reductions in state anxiety (d = 0.20, [-0.25, 0.65]) and worry (d = 0.09, [-0.36, 0.54]). SIT non-significantly attenuated state anxiety response to a single Wingate (d = 0.23, [-0.22, 0.68]), approximating a 2.5-fold reduction from pre- (d = -0.37, [-0.82, 0.09]) to post-SIT (d = -0.16, [-0.61, 0.29]). Improvements in worry (d = 0.61, [-0.04, 1.26]) and worry engagement (d = 0.60, [-0.05, 1.25]) were moderately larger among males with elevated worry. Findings indicated that a single Wingate may acutely perturb state anxiety and improve worry. Three weeks of SIT may improve anxiety and worry and response to a single Wingate. Responses were moderately larger among males with elevated worry.