The use of the integration of L-carnitine in the medical field has long been studied and several were the searches that have proved their worth, as in heart disease in patients undergoing hemodialysis in peripheral vascular insufficiency, male infertility (reduced sperm motility), hyperthyroidism.

Many researches have been made in sport where, as mentioned, the integration of L-carnitine, should ensure better performance, especially in endurance sports like cycling. To date, however, various studies did not reach a known and secure. In particular, some researchers claim to have achieved an improvement of the efficiency cardiac (decreased heart rate and improving the functions of the left ventricle) through the administration of 10 grams per day of L-carnitine (a very high dose), this research however, has never really been proven and other similarities have led to opposite results, namely that a large dose of L-carnitine has no effect on athletic performance. Even the studies on performance and recovery of marathoners did not lead to data that demonstrated the usefulness of the integration of L-carnitine in the diet of the athlete (in these studies had included the supply of 2 grams per day of L-carnitine ). Another study, however, has demonstrated how a iper L-carnitine integration promotes the oxidation of lipids compared to carbohydrates and leads to a faster recovery of heart rate. Other studies have led to the same considerations. New research, then, have shown supplementation with L-carnitine (2 to 4 grams a day) leads to the decrease in plasma lactate. Unfortunately, the limit of all studies conducted so far on the integration of L-carnitine in sport is given by the reduced practice time, from the few subjects in tests and lack of true control groups. That is now the effectiveness of the integration of L-carnitine in sport can not be said actually established, as indeed it is pointless. At the theoretical level the function and usefulness of its integration is obvious, while the scientific evidence has not yet been reached. In cycling, so if you can not defend a sword is its utility, you can not even profess his uselessness. Certainly its integration into the daily diet is not essential but may be, however, useful. Supplementation ranging from 0.5 to 3 grams per day, but it's reaching the recommended 2 grams a day for an adult subject may help long-term performance, in the mobilization of fat and reducing lactic acid production, in an easier recovery from training/competition, in reducing fat mass (associated with a reduced calorie diet). More than just before the athletic performance integration should be daily, with a possible higher dose before the race (2 grams per day rising to 3 on race day). Obviously, for long-term use is always preferable to consult with their physician. Then he saw that the scientific efficacy has not been proven it should carefully consider your body's response to the integration of L-carnitine, and decided, after an appropriate period of experimentation, if you should continue or not with its integration.