Combined Effects Of Sodium Bicarbonate And Voluntary Hyperventilation On Exercise Performance During High-intensity Intermittent Exercise

INTRODUCTION: Sodium bicarbonate ingestion is a potential strategy to mitigate performance decline during high-intensity intermittent exercise (HIIE). Concurrently, voluntary hyperventilation during recovery intervals has emerged as a comparable modality influencing exercise performance. However, it remains unclear whether the combined effects of sodium bicarbonate ingestion and hyperventilation have a stronger ergogenic effect than either single intervention. PURPOSE: To investigate the combined effects of sodium bicarbonate and voluntary hyperventilation on exercise performance during HIIE. METHODS: Eleven healthy young handball and basketball players (7 women) performed 10 sets of 10-s bouts of maximal pedaling interspaced with 50-s recovery periods. An hour before the intermittent exercise, they ingested either sodium chloride (0.208 g/kg of body weight in the control and hyperventilation [HV] groups) or sodium bicarbonate (0.3 g/kg in NaHCO3 group; 0.15 g/kg in the combined group). The control and NaHCO3 groups rested with spontaneous breathing during each recovery period, whereas the HV and combined groups performed voluntary hyperventilation 30 s before each pedaling. RESULTS: For power outputs of the control, HV, NaHCO3, and combined groups, in the first half of the exercise (sets 1-5), neither means (545±107, 549±107, 551±105, and 549±103 W, respectively) nor peaks (631±126, 643±126, 639±124, and 633±121 W, respectively) were similar among the four groups (P=0.332 and 0.343 for means and peaks, respectively). In the latter part of the exercise (sets 6-10), the means were 473±82, 492±93, 482±93, and 485±87 W, respectively, and the peaks were 551±95, 577±111, 562±116, and 564±100 W, respectively. The values were higher in the HV, NaHCO3, and combined groups compared with the control (approximately 4.5% of power improvement). However, statistical significance was not reached (P=0.223 and 0.225 for means and peaks, respectively). CONCLUSIONS: Although no statistical differences in power outputs were observed, each intervention independently attenuated performance decline in the latter part of the exercise. The combined application of sodium bicarbonate and voluntary hyperventilation did not improve exercise performance. MIZUNO SPORTS PROMOTION FOUNDATION