Four weeks of normobaric "live high-train low" do not alter muscular or systemic capacity for maintaining pH and K⁺ homeostasis during intense exercise

J Appl Physiol (1985). 2012 Jun;112(12):2027-36. doi: 10.1152/japplphysiol.01353.2011. Epub 2012 Mar 29.

Abstract

It was investigated if athletes subjected to 4 wk of living in normobaric hypoxia (3,000 m; 16 h/day) while training at 800-1,300 m ["live high-train low" (LHTL)] increase muscular and systemic capacity for maintaining pH and K(+) homeostasis as well as intense exercise performance. The design was double-blind and placebo controlled. Mean power during 30-s all-out cycling was similar before and immediately after LHTL (650 ± 31 vs. 628 ± 32 W; n = 10) and placebo exposure (658 ± 22 vs. 660 ± 23 W; n = 6). Supporting the performance data, arterial plasma pH, lactate, and K(+) during submaximal and maximal exercise were also unaffected by the intervention in both groups. In addition, muscle buffer capacity (in mmol H(+)·kg dry wt(-1)·pH(-1)) was similar before and after in both the LHTL (140 ± 12 vs. 140 ± 16) and placebo group (145 ± 2 vs. 140 ± 3). The expression of sarcolemmal H(+) transporters (Na(+)/H(+) exchanger 1, monocarboxylate transporters 1 and 4), as well as expression of Na(+)-K(+) pump subunits-α(1), -α(2), and -β(1) was also similar before and after the intervention. In conclusion, muscular and systemic capacity for maintaining pH and K(+) balance during exercise is similar before and after 4 wk of placebo-controlled normobaric LHTL. In accordance, 30-s all-out sprint ability was similar before and after LHTL.

Publication types

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

MeSH terms

  • Adult
  • Altitude
  • Bicarbonates / metabolism
  • Carbon Dioxide / metabolism
  • Double-Blind Method
  • Exercise / physiology*
  • Exercise Test / methods
  • Female
  • Homeostasis / physiology
  • Humans
  • Hydrogen-Ion Concentration
  • Hypoxia / metabolism
  • Hypoxia / physiopathology
  • Lactic Acid / metabolism
  • Lanthanum / metabolism
  • Male
  • Muscle, Skeletal / metabolism
  • Muscle, Skeletal / physiology*
  • Oxygen Consumption / physiology
  • Potassium / metabolism*
  • Sodium-Potassium-Exchanging ATPase / metabolism
  • Task Performance and Analysis

Substances

  • Bicarbonates
  • Carbon Dioxide
  • Lactic Acid
  • Lanthanum
  • Sodium-Potassium-Exchanging ATPase
  • Potassium