Carnitine is synthesized from the amino acids lysine and methionine. Many active adults use it in supplemental form, but its impact on exercise performance isn’t well understood. Research published in the journal Cell Metabolism shows how this popular ingredient works with an enzyme called carnitine acetyltransferase, or CrAT, to increase muscle stamina in mice.
Scientists created a group of mice with CrAT deficiency in skeletal muscle. Compared to normal rodents they tired of exercise earlier. Then both groups were supplemented with carnitine. As expected, there was no change in the CrAT deficient mice. But the normal mice showed an even greater tolerance for exercise.
True Strength Moment: Researchers think that carnitine works with the CrAT enzyme to optimize muscle energy metabolism in mice. How or even if this mechanism works in a similar way for humans is unknown.