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Peer Reviewed Studies Discussion / Re: sodium and endurance
« on: December 22, 2015, 04:21:51 pm »
http://download.springer.com/static/pdf/802/art%253A10.1186%252F1550-2783-10-16.pdf?originUrl=http%3A%2F%2Fjissn.biomedcentral.com%2Farticle%2F10.1186%2F1550-2783-10-16&token2=exp=1450819403~acl=%2Fstatic%2Fpdf%2F802%2Fart%25253A10.1186%25252F1550-2783-10-16.pdf*~hmac=99cc7c4b97aea02fe10c4102be86f13ad101409a58e2257cb5fb6afe28a73bd3
Multiday acute sodium bicarbonate intake improves endurance capacity and reduces acidosis in men
Multiday acute sodium bicarbonate intake improves endurance capacity and reduces acidosis in men
Quote
Abstract
Background: The purpose was to investigate the effects of one dose of NaHCO3 per day for five consecutive days
on cycling time-to-exhaustion (Tlim) at ‘Critical Power’ (CP) and acid–base parameters in endurance athletes.
Methods: Eight trained male cyclists and triathletes completed two exercise periods in a randomized, placebo-controlled,
double-blind interventional crossover investigation. Before each period, CP was determined. Afterwards, participants
completed five constant-load cycling trials at CP until volitional exhaustion on five consecutive days, either after a dose
of NaHCO3 (0.3 g·kg−1 body mass) or placebo (0.045 g·kg−1 body mass NaCl).
Results: Average Tlim increased by 23.5% with NaHCO3 supplementation as compared to placebo (826.5 ± 180.1 vs.
669.0 ± 167.2 s; P = 0.001). However, there was no time effect for Tlim (P = 0.375). [HCO3
−
] showed a main effect for
condition (NaHCO3: 32.5 ± 2.2 mmol·l−1
; placebo: 26.2 ± 1.4 mmol·l−1
; P < 0.001) but not for time (P = 0.835). NaHCO3
supplementation resulted in an expansion of plasma volume relative to placebo (P = 0.003).
Conclusions: The increase in Tlim was accompanied by an increase in [HCO3
−
], suggesting that acidosis might be a
limiting factor for exercise at CP. Prolonged NaHCO3 supplementation did not lead to a further increase in [HCO3
−
] due
to the concurrent elevation in plasma volume. This may explain why Tlim remained unaltered despite the prolonged
NaHCO3 supplementation period. Ingestion of one single NaHCO3 dose per day before the competition during
multiday competitions or tournaments might be a valuable strategy for performance enhancement.
