Dose-Response of Sodium Bicarbonate Ingestion Highlights Individuality in Time Course of Blood Analyte Responses.
To defend against hydrogen cation accumulation and muscle fatigue during exercise, sodium bicarbonate (NaHCO3) ingestion is commonplace. The individualized dose-response relationship between NaHCO3ingestion and blood biochemistry is unclear. The present study investigated the bicarbonate, pH, base excess and sodium responses to NaHCO3ingestion. Sixteen healthy males (23 ± 2 years; 78.6 ± 15.1 kg) attended three randomized order-balanced, nonblinded sessions, ingesting a single dose of either 0.1, 0.2 or 0.3 g·kg-1BM of NaHCO3(Intralabs, UK). Fingertip capillary blood was obtained at baseline and every 10 min for 1 hr, then every 15 min for a further 2 hr. There was a significant main effect of both time and condition for all assessed blood analytes (p ≤ .001). Blood analyte responses were significantly lower following 0.1 g·kg-1BM compared with 0.2 g·kg-1BM; bicarbonate concentrations and base excess were highest following ingestion of 0.3 g·kg-1BM (p ≤ .01). Bicarbonate concentrations and pH significantly increased from baseline following all doses; the higher the dose the greater the increase. Large interindividual variability was shown in the magnitude of the increase in bicarbonate concentrations following each dose (+2.0-5; +5.1-8.1; and +6.0-12.3 mmol·L-1for 0.1, 0.2 and 0.3 g·kg-1BM) and in the range of time to peak concentrations (30-150; 40-165; and 75-180 min for 0.1, 0.2 and 0.3 g·kg-1BM). The variability in bicarbonate responses was not affected by normalization to body mass. These results challenge current practices relating to NaHCO3supplementation and clearly show the need for athletes to individualize their ingestion protocol and trial varying dosages before competition.
Rebecca Louise
RL
Jones
Trent
T
Stellingwerff
Guilherme Giannini
GG
Artioli
Bryan
B
Saunders
Simon
S
Cooper
Craig
C
Sale
D000328:Adult; D056352:Athletes; D054874:Athletic Performance; D015992:Body Mass Index; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D015444:Exercise; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007206:Individuality; D016014:Linear Models; D008297:Male; D018763:Muscle Fatigue; D017693:Sodium Bicarbonate / Q000008:administration & dosage* / Q000097:blood*; D055815:Young Adult
D017693:Sodium Bicarbonate
extracellular buffering; fatigue; pH