• Media type: E-Article
  • Title: Sodium bicarbonate ingestion augments the increase in PGC-1α mRNA expression during recovery from intense interval exercise in human skeletal muscle
  • Contributor: Percival, Michael E.; Martin, Brian J.; Gillen, Jenna B.; Skelly, Lauren E.; MacInnis, Martin J.; Green, Alex E.; Tarnopolsky, Mark A.; Gibala, Martin J.
  • imprint: American Physiological Society, 2015
  • Published in: Journal of Applied Physiology
  • Language: English
  • DOI: 10.1152/japplphysiol.00048.2015
  • ISSN: 1522-1601; 8750-7587
  • Origination:
  • Footnote:
  • Description: <jats:p> We tested the hypothesis that ingestion of sodium bicarbonate (NaHCO<jats:sub>3</jats:sub>) prior to an acute session of high-intensity interval training (HIIT) would augment signaling cascades and gene expression linked to mitochondrial biogenesis in human skeletal muscle. On two occasions separated by ∼1 wk, nine men (mean ± SD: age 22 ± 2 yr, weight 78 ± 13 kg, V̇o<jats:sub>2 peak</jats:sub> 48 ± 8 ml·kg<jats:sup>−1</jats:sup>·min<jats:sup>−1</jats:sup>) performed 10 × 60-s cycling efforts at an intensity eliciting ∼90% of maximal heart rate (263 ± 40 W), interspersed with 60 s of recovery. In a double-blind, crossover manner, subjects ingested a total of 0.4 g/kg body weight NaHCO<jats:sub>3</jats:sub> before exercise (BICARB) or an equimolar amount of a placebo, sodium chloride (PLAC). Venous blood bicarbonate and pH were elevated at all time points after ingestion ( P &lt; 0.05) in BICARB vs. PLAC. During exercise, muscle glycogen utilization (126 ± 47 vs. 53 ± 38 mmol/kg dry weight, P &lt; 0.05) and blood lactate accumulation (12.8 ± 2.6 vs. 10.5 ± 2.8 mmol/liter, P &lt; 0.05) were greater in BICARB vs. PLAC. The acute exercise-induced increase in the phosphorylation of acetyl-CoA carboxylase, a downstream marker of AMP-activated protein kinase activity, and p38 mitogen-activated protein kinase were similar between treatments ( P &gt; 0.05). However, the increase in PGC-1α mRNA expression after 3 h of recovery was higher in BICARB vs. PLAC (approximately sevenfold vs. fivefold compared with rest, P &lt; 0.05). We conclude that NaHCO<jats:sub>3</jats:sub> before HIIT alters the mRNA expression of this key regulatory protein associated with mitochondrial biogenesis. The elevated PGC-1α mRNA response provides a putative mechanism to explain the enhanced mitochondrial adaptation observed after chronic HIIT supplemented with NaHCO<jats:sub>3</jats:sub> in rats. </jats:p>
  • Access State: Open Access