Aerobic vs. Anaerobic Metabolism

When a cell metabolizes one molecule of glucose by aerobic metabolism (with oxygen) it produces thirty-six ATP molecules, the energy “battery” in the cells. However, when one molecule of glucose is metabolized anaerobically (without oxygen) it produces two ATP molecules. The products from aerobic metabolism are carbon dioxide and water, which are readily cleared. The product from anaerobic metabolism is lactic acid, which goes on to create muscle pain.

Each ATP molecule requires one atom of Mg2+, which means that aerobic metabolism requires 18X more magnesium than anaerobic metabolism. The significance being that if available magnesium ions are limited, the body must switch to anaerobic metabolism, with the built-in limiting mechanism of lactic acid build-up. Anaerobic metabolism is the only known biochemical source of lactic acid in the human body.

Lance Armstrong’s Secret?

Lance Armstrong’s documented ability to maintain aerobic metabolism in the mountains, while his adversaries fell by the wayside, crippled by anaerobic lactic acid build-up, demonstrates the importance of properly fueling aerobic metabolism. There are a number of nutrients and factors required for continuous aerobic metabolism, but magnesium is the only limiting mineral of those factors; it cannot be created by the body and must be ingested everyday in sufficient quantities. Obviously, Lance Armstrong, when he set his records, had a total sufficiency of available magnesium ions and most likely a greater sufficiency than his competitors.

Studies have shown that a typical aggressive workout uses up 300 mg of magnesium. That’s in addition to the 420 mg RDA for males. Strenuous, prolonged workouts or competition might use upward of 1,200 to 1,500 mg of magnesium (an extrapolation). Are you getting these amounts in your diet and supplementation regimen? As an example, if you are using sport nutrition products, we don’t see how that could be possible, as they simple don’t provide enough magnesium in their recommended doses (see “Comparison – EndurHance ™ and Sport-Focused Magnesium”).

Magnesium is Key!

To create one molecule of ATP requires one atom of Mg2+.

“Magnesium not only is required for the hydrolysis of ATP so that muscle contraction can proceed normally but also is essential for the building of crucial regulatory and contractile muscle proteins. Inadequate amounts of Mg will compromise muscle building and subsequent contractions and limit the performance of both anaerobic and aerobic activities.” (1)

(1) Macroelements, Water, and Electrolytes in Sports Nutrition, Judy A. Driscoll and Ira Wolinsky, 1999 p. 58