Sodium bicarbonate ingestion augments the increase in PGC-1α mRNA expression during recovery from intense interval exercise in human skeletal muscle

J Appl Physiol (1985). 2015 Dec 1;119(11):1303-12. doi: 10.1152/japplphysiol.00048.2015. Epub 2015 Sep 17.


We tested the hypothesis that ingestion of sodium bicarbonate (NaHCO3) 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(2 peak) 48 ± 8 ml·kg(-1)·min(-1)) 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 NaHCO3 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 < 0.05) in BICARB vs. PLAC. During exercise, muscle glycogen utilization (126 ± 47 vs. 53 ± 38 mmol/kg dry weight, P < 0.05) and blood lactate accumulation (12.8 ± 2.6 vs. 10.5 ± 2.8 mmol/liter, P < 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 > 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 < 0.05). We conclude that NaHCO3 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 NaHCO3 in rats.

Keywords: glycogen; high-intensity interval training; mitochondria; supplementation.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Bicarbonates / blood
  • Cross-Over Studies
  • Double-Blind Method
  • Exercise / physiology*
  • Glycogen / metabolism
  • Heart Rate / physiology
  • Humans
  • Male
  • Mitochondria, Muscle / metabolism
  • Muscle, Skeletal / metabolism
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • Phosphorylation
  • RNA, Messenger / biosynthesis*
  • Sodium Bicarbonate / pharmacology*
  • Transcription Factors / biosynthesis*
  • Young Adult
  • p38 Mitogen-Activated Protein Kinases / biosynthesis
  • p38 Mitogen-Activated Protein Kinases / genetics


  • Bicarbonates
  • PPARGC1A protein, human
  • Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
  • RNA, Messenger
  • Transcription Factors
  • Sodium Bicarbonate
  • Glycogen
  • p38 Mitogen-Activated Protein Kinases