The dose-response to sodium bicarbonate ingestion highlights the need for individuality in supplementation
Year: 2024
Type: conference-paper
Abstract: High-intensity exercise results in increased hydrogen cation (H+) production in the working muscle, reducing intracellular pH and potentially resulting in muscular fatigue. To reduce H+ accumulation and thus muscular fatigue, alkalinising agents such as sodium bicarbonate (NaHCO3) are ingested to defend against these local changes. Athletes are widely recommended to consume NaHCO3 in doses of 0.2–0.4 g · kg?1 BM to increase blood bicarbonate concentrations, supporting this defensive buffering process. Despite this, the dose–response relationship of blood responses (pH, bicarbonate and base excess) following ingestion of different doses of NaHCO3 has not been well studied. Therefore, the purpose of this investigation was to examine the effect of different NaHCO3 doses on pH, bicarbonate and base excess. Following institutional ethical approval, 16 healthy young males (age, 23 ± 2 years; height, 1.80 ± 0.07 m; body mass, 78.6 ± 15.1 kg) attended three sessions, ingesting a single dose (0.1, 0.2 or 0.3 g · kg?1 BM) of NaHCO3(Intralabs, UK) on each occasion. Capillary blood samples were obtained at baseline and every 10 min for 1 h, then every 15 min for a further 2 h. Data were analysed using repeated measures ANOVA; significance was accepted at P < 0.05. There was a significant main effect of dose on pH, bicarbonate and base excess (all P < 0.001). The 0.1 g · kg?1 BM dose responses were significantly lower than the 0.2 g · kg?1 BM (pH, bicarbonate and base excess; all P < 0.003) and 0.3 g · kg?1 BM (pH, bicarbonate and base excess; all P < 0.001) doses. Likewise following 0.3 g · kg?1 BM bicarbonate and base excess responses were higher than responses following 0.2 g · kg?1 BM (both P < 0.01). Furthermore, for all assessed variables, alarge inter-individual variability in absolute peak responses and the timing of the peaks relative to ingestion was shown. The main findings of the present study are that the blood responses (pH, bicarbonate and base excess) following NaHCO3 ingestion are increased, and although the magnitude of the change is greaterwith larger doses of NaHCO3, there is a considerable degree of inter-individual variability. Evaluation of the individual responses to sodium bicarbonate ingestion starts to question whether the most commonly implemented supplementation protocol of 0.3 g · kg?1 BM administered ~60 min prior to performance is the most beneficial for all individuals. Due to the reported high levels of inter-individual variability, an important practical consideration for athletes ingesting NaHCO3 is to individualise the protocols undertaken and ensure that they are tested prior to use in competition.
Source: Figshare
Authors: Craig Sale (723461), Simon Cooper (723455), Rebecca Jones (17161051)
Language: English
Subfield: Orthopedics and Sports Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7018569349