THE EFFECT OF SODIUM BICARBONATE ON ACUTE KIDNEY INJURY MARKERS DURING PHYSICAL WORK IN THE HEAT
Date
2023-07-28
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Saudi Digital Library
Abstract
Sodium bicarbonate supplementation (NaHCO3) before physical work in the heat may reduce
the risk of developing acute kidney injury (AKI). Purpose: To determine the effects of
NaHCO3 supplementation before a prolonged bout of physical work in the heat on AKI
markers and kidney function. Method: A randomized, cross-over, double blinded design was
conducted on 8 participants (3 females) who consumed NaHCO3 (0.2 g/kg body weight) or
placebo (CON) before prolonged (120 minutes) moderate intensity (~65% of maximal heart
rate) physical work in the heat (40℃ and 23% relative humidity (RH)). Blood and urine
samples were collected pre, post, and 1hr post exercise. Core temperature (Tc) and heart rate
(HR) were measured every three minutes, and perceptual variables [i.e., rating of perceived
exertion (RPE), thermal sensation (TS), and comfort scale (CS)] were measured every 6
minutes. Gastrointestinal discomfort (GI) was evaluated pre- and post NaHCO3 or placebo
(CON) ingestion, within 1hr of the physical work, post physical work, and 1hr post physical
work. Urine flow rate (UFR) was calculated pre and 1hr post physical work. Urine osmolality
(Uosm) and creatinine (uCr) and plasma osmolality (Posm) were assessed pre, post, and 1hr
post physical work. Insulin-like growth factor binding protein 7 (IGFBP7), tissue inhibitor of
metalloproteinase 2 (TIMP-2), and neutrophil gelatinase-associated lipocalin (NGAL) were
measured in the urine pre and 1hr post physical work. Results: Physiological, perceptual, and
GI parameters increased over time (p < 0.05), but they were not different between conditions
(p > 0.05). Uosm was higher in CON compared to NaHCO3 (p = 0.011) post exercise. UFR
was lower in CON compared to NaHCO3 at 1 hour post exercise (p = 0.042). Urine TIMP-2
corrected for UFR was higher in CON compared to NaHCO3 (p =0.040). IGFBP-7 × TIMP-2
corrected for UFR trended to be lower in NaHCO3 (p = 0.062). Conclusion: NaHCO3
72
ingestion pre-physical work in the heat reduced markers of AKI and increased UFR
suggesting less stress to the kidneys.
Description
I have added the transcript of summer 2023 including the PEP-699 Dissertation credit.
Keywords
Heat, sodium bicarbonate, acute kidney injury, kidney function, physical work, exercise