L-Carnitine and Physical Performance

A number of studies have focused on the effect of exercise on
carnitine status in both humans and animals. Severe bouts of
exercise (letting off to a particularly good track) result in a
significant drop in muscle carnitine levels and a coincident
increase in the urinary excretion of this nutrient, underlining
the importance of carnitine in athletic performance.

Branched chain amino acid (BCAA) metabolism
Recent studies have shown that carnitine levels are linked to
the metabolism of BCAA's, considered the most important amino
acid for sports performance4.