Sodium Bicarbonate Supplementation Does Not Improve Running Anaerobic Sprint Test Performance in Semiprofessional Adolescent Soccer Players

Abstract

Ergogenic strategies have been studied to alleviate muscle fatigue and improve sports performance. Sodium bicarbonate (NaHCO3) has improved repeated sprint performance in adult team-sports players, but the effect for adolescents is unknown. The aim of the present study was to evaluate the effect of NaHCO3 supplementation on repeated sprint performance in semiprofessional adolescent soccer players. In a double-blind, placebo-controlled, crossover trial, 15 male semiprofessional adolescent soccer players (15 ± 1 years; body fat 10.7 ± 1.3%) ingested NaHCO3 or a placebo (sodium chloride) 90 min before performing the running anaerobic sprint test (RAST). A countermovement jump was performed before and after the RAST, and ratings of perceived exertion, blood parameters (potential hydrogen and bicarbonate concentration), and fatigue index were also evaluated. Supplementation with NaHCO3 promoted alkalosis, as demonstrated by the increase from the baseline to preexercise, compared with the placebo (potential hydrogen: +0.07 ± 0.01 vs. −0.00 ± 0.01, p < .001 and bicarbonate: +3.44 ± 0.38 vs. −1.45 ± 0.31 mmol/L, p < .001); however, this change did not translate into an improvement in RAST total time (32.12 ± 0.30 vs. 33.31 ± 0.41 s, p = .553); fatigue index (5.44 ± 0.64 vs. 6.28 ± 0.64 W/s, p = .263); ratings of perceived exertion (7.60 ± 0.33 vs. 7.80 ± 0.10 units, p = .525); countermovement jump pre-RAST (32.21 ± 3.35 vs. 32.05 ± 3.51 cm, p = .383); or countermovement jump post-RAST (31.70 ± 0.78 vs. 32.74 ± 1.11 cm, p = .696). Acute NaHCO3 supplementation did not reduce muscle fatigue or improve RAST performance in semiprofessional adolescent soccer players. More work assessing supplementation in this age group is required to increase understanding in the area.

The time to peak blood bicarbonate (HCO3–), pH, and the strong ion difference (SID) following sodium bicarbonate (NaHCO3) ingestion in highly trained adolescent swimmers

“…The participants in the present study demonstrated a peak blood HCO 3 concentration that exceeded the 5-6 mmol�L -1 threshold (+6.8 ± 2.4 mmol�L -1 ), contrasting previous studies when trained adolescents ingested NaHCO 3 prior to exercise [34,35]. A possible explanation for this difference is that high-level swimmers often have an early maturation onset [45], which likely occurred in the current participants and aided their selection for the high-performance swimming programme in which they were recruited.…”

“…Surprisingly, both studies by Gough et al demonstrated greater group mean increases in the SID compared to the present study (+4 vs. +6-10 mEq�L -1 ), despite not purposely seeking to identify a peak concentration. The current study also observed lower baseline (33)(34)(35)(36)(37)(38) ) and absolute peak SID concentrations (37 vs. 42-46 mEq�L -1 ), inferring that adolescents might also be limited with their capacity for strong ion movements (e.g., reduced Na + /K + pump activity) [48]. Furthermore, these lower concentrations occurred despite food consumption 1-3 hours before NaHCO 3 ingestion, though the energy, macronutrient, or electrolyte (Na + , K + , Cl -, and Ca 2+ ) composition of this meal was not correlated with baseline SID or the absolute SID increases that were achieved.…”

“…Moreover, whether NaHCO 3 supplementation is appropriate for trained adolescents is unclear, with there being little evidence to suggest that large increases in blood alkalosis occur following ingestion. For example, neither Zajac et al (+3.4 mmol�L -1 [34]) or Guimarães et al (+3.4 mmol�L -1 [35]) observed a blood HCO 3 increase above the proposed +5 mmol�L -1 'ergogenic threshold' when measured at 60 and 90 min post-ingestion, respectively. Despite similar HCO 3 increases, however, both of these studies differed in performance outcomes (time to complete 4 x 50 m swimming sprints: 1.3% faster [34] vs. time to complete 6 x 35 m running sprints: no change [35]).…”

“…For example, neither Zajac et al (+3.4 mmol�L -1 [34]) or Guimarães et al (+3.4 mmol�L -1 [35]) observed a blood HCO 3 increase above the proposed +5 mmol�L -1 'ergogenic threshold' when measured at 60 and 90 min post-ingestion, respectively. Despite similar HCO 3 increases, however, both of these studies differed in performance outcomes (time to complete 4 x 50 m swimming sprints: 1.3% faster [34] vs. time to complete 6 x 35 m running sprints: no change [35]). Why this discrepancy occurred remains unknown, though the authors speculated that individual factors such as genetics and gastrointestinal (GI) physiology may have had a role [35].…”

“…Despite similar HCO 3 increases, however, both of these studies differed in performance outcomes (time to complete 4 x 50 m swimming sprints: 1.3% faster [34] vs. time to complete 6 x 35 m running sprints: no change [35]). Why this discrepancy occurred remains unknown, though the authors speculated that individual factors such as genetics and gastrointestinal (GI) physiology may have had a role [35]. Indeed, both studies did not account for individual differences since standardized ingestion strategies were employed and HCO 3 changes were reported at the group level only.…”