Purpose: This study investigated the effects of repeated sprint training in hypoxia (RSH) induced by voluntary hypoventilation (VHL) on sport-specific performance in elite epee fencers. Methods: Twenty-two elite-level fencers (national to international level) were randomly assigned to 8 sessions of repeated sprint training over 4 weeks. Training was performed either in hypoxia induced by VHL (RSH-VHL, n = 11) or with unrestricted breathing (repeated sprint in normoxia [RSN], n = 11). It consisted of repeated 15-second maximal fencing sprints with 15-second semiactive recovery (work:rest ratio 1:1). Performance was assessed before (pre) and after (post) the intervention using a dual-component fencing test that involved repeated maximal lunges (sprints) immediately followed by a technical task (reaction time and accuracy assessment on an electronic target) before the next repetition. Results: Both groups showed similar significant improvements in best sprint time (RSH-VHL: −5.1%; RSN: −5.7%), mean sprint time (RSH-VHL: −6.8%; RSN: −7.0%), and sprint decrement score (RSH-VHL: −31.6%; RSN: −23.1%) (P ≤.003). However, physiological and technical adaptations differed. In the RSH-VHL group, maximal and mean heart rates decreased significantly (−4.7% and −5.7%, respectively) (P textless .001), whereas no significant changes were observed in the RSN group (−0.7% and −0.5%, respectively). Additionally, RSH-VHL prevented the increase in technical alteration under fatigue observed in RSN (reaction time decrement: −3.0% vs 15.7%; P = .005). Conclusion: RSH-VHL training mitigates the decline in technical performance (reaction time) under fatigue and improves cardiovascular efficiency in elite epee fencers. These findings suggest that VHL is a valuable, equipment-free method to enhance both physical and technical resilience during high-intensity fencing bouts.