The effect of β-alanine and NaHCO3 co-ingestion on buffering capacity and exercise performance with high-intensity exercise in healthy males

Abstract

Introductionβ-alanine (BAl) and NaHCO3 (SB) ingestion may provide performance benefits by enhancing concentrations of their respective physiochemical buffer counterparts, muscle carnosine and blood bicarbonate, counteracting acidosis during intense exercise. This study examined the effect of BAl and SB co-supplementation as an ergogenic strategy during high-intensity exercise.MethodsEight healthy males ingested either BAl (4.8 g day−1 for 4 weeks, increased to 6.4 g day−1 for 2 weeks) or placebo (Pl) (CaCO3) for 6 weeks, in a crossover design (6-week washout between supplements). After each chronic supplementation period participants performed two trials, each consisting of two intense exercise tests performed over consecutive days. Trials were separated by 1 week and consisted of a repeated sprint ability (RSA) test and cycling capacity test at 110 % Wmax (CCT110 %). Placebo (Pl) or SB (300 mg kgbw−1) was ingested prior to exercise in a crossover design to creating four supplement conditions (BAl-Pl, BAl-SB, Pl–Pl, Pl-SB).ResultsCarnosine increased in the gastrocnemius (n = 5) (p = 0.03) and soleus (n = 5) (p = 0.02) following BAl supplementation, and Pl-SB and BAl-SB ingestion elevated blood HCO3− concentrations (p < 0.01). Although buffering capacity was elevated following both BAl and SB ingestion, performance improvement was only observed with BAl-Pl and BAl-SB increasing time to exhaustion of the CCT110 % test 14 and 16 %, respectively, compared to Pl–Pl (p < 0.01).ConclusionSupplementation of BAl and SB elevated buffering potential by increasing muscle carnosine and blood bicarbonate levels, respectively. BAl ingestion improved performance during the CCT110 %, with no aggregating effect of SB supplementation (p > 0.05). Performance was not different between treatments during the RSA test.

Sodium bicarbonate ingestion and individual variability in time-to-peak pH

“…Indeed, such is the wealth of published studies on sodium bicarbonate, that recently, researchers have started to focus on its co-ingestion with other active ingredients such as caffeine 24,25 and -alanine 26,27,28 in order to assess the potential additive effects in order to provide further performance enhancements via the activation of different ergogenic mechanisms simultaneously.…”

β–alanine: performance effects, usage and side effects

“…Danaher et al [4] also reported no influence on performance following NaHCO3 supplementation in men using a similar dosage and testing protocol to those used in the present study. Despite a significant increase in pre-exercise blood bicarbonate following supplementation in their study, the authors stated that metabolic alkalosis was not achieved due to a lack of change in blood pH following NaHCO3 supplementation [4]. They did not elucidate why there was no change, as several investigations using the same protocol have previously shown changes in pH after the ingestion of similar doses of NaHCO3 [224,252,253].…”

“…Using an almost identical testing and dosage protocol to that used in the present study, Danaher et al [4] reported no change in RSA performance after six weeks of β-alanine supplementation (4.8 g·day −1 for 4 weeks, 6.4 g·day −1 for final 2 weeks). However, participants did not train during the supplementation period.…”

“…However, participants did not train during the supplementation period. Additionally, Danaher et al [4] used a crossover design that included a six week washout period which may not have been sufficient to decrease muscle carnosine levels to baseline [101] and that consequently may have confounded their results. In contrast to the present findings, Sweeney et al [132] reported no significant improvements in repeated non-motorised treadmill running performance (2 sets of 5 x 5 sec sprints with 45 sec rest between sprints) using a similar total dose of β-alanine in active males.…”

“…Results have been mixed, with additive benefits reported for upper-body intermittent performance [133] and small non-significant but likely increases in performance reported in cycle capacity [116,162], 2000m rowing [242] plus 100 m and 200m swimming [120]. Other studies have reported no additive benefit for cycle capacity [4] and RSA during cycling and running [4,146,238]. However, these studies were limited by small sample sizes and did not include any structured training during the supplementation period.…”