Sodium bicarbonate supplementation improves the subjective perception of fatigue but not the performance of amateur runners

Introduction and Aim: The sodium bicarbonate, as ergogenic aids, has been propose for performance improvement of long-distances runners, as well as reducing muscular fatigue, reducing agent of lactate accumulation in muscle and in acid-base balance in athletes of several sporting modalities. Therefore, this study aimed to investigate the effect of sodium bicarbonate supplementation on performance of 6-km amateur runners. Materials and Methods: quasi-experimental study with 12 amateur runners, both sexes and aged between 18-57 years. In different days, runners ingested of sodium bicarbonate (0.15g . kg(-1)) or no and performed 2 rustics of 6km simulated street race competition. Specific physical tests, such as blood lactate, urinary pH and heart rate were evaluated before and after each run. Subjective perception of fatigue was evaluated only after running. Results: Runners performance did not show significant difference between runs (p=0.771), however, 41.67% of runners reported a decrease in perception of effort after sodium bicarbonate supplementation. Heart rate also did not show significant difference in rest (p=0.978), after running (p=0.592) or in variation of heart rate (p=0.267). It was verified a significant increasing in blood lactate variation after sodium bicarbonate supplementation (p=0.048), as well as a significant increasing in urinary pH (p=0.037). Conclusion: Our data demonstrate that sodium bicarbonate supplementation did not improve performance but improved subjective perception of fatigue, as well as increase the blood lactate variation and urinary pH.