A nutritional supplement that may offer improved healing after muscle damage is L-carnitine. Although carnitine, which is an amino acid by-product, is more often associated with fat mobilization, researchers from Ball State University in Indiana tested its effects in 10 healthy men engaged in high-intensity weight training. The men took either a placebo or two grams a day of L-carnitine three weeks before doing a high-intensity squat protocol.
The men using carnitine experienced enhanced muscle recovery after high-intensity exercise. The researchers thought the effect was due to reduced muscle damage during exercise, enhanced fat metabolism and an improved carrying capacity of insulinlike growth factor (IGF-1) in the blood due to higher levels of the protein that binds with it (IGFBP-3). That makes sense, since IGF-1 helps repair damaged muscles after intense exercise. IM