Friday, April 25, 2014

The "Lactate Paradox"

Lower peak lactate levels at high altitudes

Oxidative phosphyorlation is a consumer of NADH + H+. But at altitude or under hypoxic conditions, an individual's ability to utilize oxidative phosphorylation is negatively affected by the decreased availibility of O2. Consequently, NADH + H+ accumulates and acidosis occurs. H+ accumulation inhibits glycolysis. Inhibition of glycolysis = decreased pyruvate and lactate production.

Further, at altitude respiration rate increases at rest. This increases blood pH. This increase in pH at rest causes bicarbonate to be excreted from the kidneys. Loss of bicarbonate reduces the athlete's ability to buffer H+. H+ accumulation ---> acidosis ---> inhibition of glycolysis ---> decreased lactate production.

Again, could supplementation with beta-alanine limit acidosis, offset the lactate paradox, and maintain work capacity at altitude?

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