Table 10.

Sodium bicarbonate (NaHCO₃) supplementation in endurance.

Research	Athletes	Supplementation (Type/Dose)	Side Effects		Effects of NaHCO3
McClung et al., 2007 [196]	Endurance athletes	Fluid solution; 0.3 g/kg BM	Mild	YES	NaHCO3 resulted in performance improvement and lowered blood lactate (F(1,15) = 51.4; p < 0.001; η2 = 0.774)
Lindh et al., 2008 [197]	Elite swimmers	Capsule; 0.3 g/kg BM	None	YES	NaHCO3 improved performance in eight out of nine athletes by 1.6% (p = 0.04)
Pruscino et al., 2008 [198]	High elite swimmers	Capsule; 0.3 g/kg BM	N/A	NO	No significant improvement in time after ingestion of NaHCO3 (ES = 0.25 ± 0.26; p = 0.052)
Zajac et al., 2009 [199]	Well-trained swimmers	Fluid solution; 0.3 g/kg BM	None	YES	NaHCO3 ingestion improves performance by 1.5 s compared to controls (F(2,28) = 5.63; p < 0.05)
Siegler et al., 2010 [200]	University swimmers	Fluid solution; 0.3 g/kg BM	None	YES	NaHCO3 improved total swim time by 2%. Mean difference overall was 4.4 s (d = 0.15; p = 0.04)
Kilding et al., 2012 [201]	Well-trained cyclists	Capsule; 0.3 g/kg BM	Mild	YES	Caffeine and NaHCO3 consumed separately led to performance enhancements (ES = 0.21; p = 0.01)
Joyce et al., 2012 * [202]	Competitive swimmers	Capsule; 0.1 g/kg BM	Mild	NO	Chronic supplementation of NaHCO3 had no effect on swimming performance (F = 0.48; p = 0.8)
Joyce et al., 2012 * [202]	Competitive swimmers	Capsule; 0.3 g/kg BM	Mild	NO	Acute supplementation of NaHCO3 had no effect on swimming performance (F = 0.48; p = 0.08).
Kupcis et al., 2012 [203]	Lightweight rowers	Capsule; 0.3 g/kg BM	None	NO	NaHCO3 provides no benefit for rowing performance (p = 0.41; ES: 0.05)
Tobias et al., 2013 [204]	Competitive swimmers	Capsule; 0.3 g/kg BM	Mild	YES/NO	Combined with BA, NaHCO3 improved 200 m time (F = 1.36; p = 0.28), but not 100 m (F = 5.17; p = 0.024).
Mero et al., 2013 [205]	Competitive swimmers	Capsule; 0.3 g/kg BM	None	YES	NaHCO3 improves swimming performance by 2.4%/1.5 s (p < 0.05)
Mueller et al., 2013 [206]	Cyclists/triathletes	Tablet; 0.3 g/kg BM	N/A	YES	NaHCO3 improved time to exhaustion compared to a placebo (+23.5%) (F(1,7) = 35.45; p = 0.001 η2 = 0.84).
Driller et al., 2013 [207]	National team rowers	Capsule; 0.3 g/kg BM	Mild	NO	Serial supplementation of NaHCO3 before HIT provides no benefits to performance (p > 0.05)
Hobson et al., 2013 [208]	Well-trained rowers	Capsule; 0.3 g/kg BM	None to Severe	NO	Neither NaHCO3 or Beta alanine (or combined) have an effect on performance (p < 0.05)
Hobson et al., 2014 [209]	Well-trained rowers	Capsule; 0.3 g/kg BM	None to Severe	NO	Ingestion of NaHCO3 has no effect on rowing performance (p < 0.09)
Stöggl et al., 2014 [210]	Endurance athletes	Fluid solution; 0.3 g/kg BM	Mild	NO	Improvements in lactate, blood pH, and HCO3− were found while supplementing NaHCO3 (p < 0.01)
Christensen et al., 2014 [211]	Lightweight rowers	Capsule; 0.3 g/kg BM	None	YES/NO	Solely, NaHCO3 has no effect, but combined with caffeine (ES: 0.6; p < 0.01)
Egger et al., 2014 [212]	Trained cyclists	Fluid solution; 0.3 g/kg BM	None	YES	Cycling time to exhaustion was improved under NaHCO3 compared to a placebo (ES: 0.6; p < 0.05)
Thomas et al., 2016 [213]	Trained cyclists	Capsule; 0.3 g/kg BM	N/A	YES	Lesser VO2 and VE decrease during trial while supplementing NaHCO3 (r = 0.74; p < 0.01)
Freis et al., 2017 [214]	Endurance ath- letes	Fluid Solution; 0.3 g/kg BM	Severe	YES/NO	NaHCO3 led to no change in time to exhaustion but higher maximum running speed (p = 0.009)

g: gram; kg: kilogram; BM: body mass; min: NaHCO₃: sodium bicarbonate; BA: beta-alanine; N/A: not applicable; Mild: minimum discomfort; None: no discomfort; VO2: oxygen consumption; VE: ventilation; F: Fishers F test; d = Cohen’s d; ES: effect size; r = Pearson correlation; Severe: serious discomfort; η² = eta squared. * The study examined the effects of both short-term and long-term use of the substance, and these were analyzed independently.