L-carnitine is actually an amino acid existing in human body. Supplement can improve the energy supply efficiency of the body and increase the consumption of fat. According to scientific research, L-carnitine will take effect after one hour and last for six hours, so it should be taken before training, and it is best to train after 1 hour, especially aerobic exercise such as running, so that you can feel abundant physical strength. There are some precautions about the taking method of nutrend L-carnitine. First, the dose should be controlled at 1 1,000 mg to 5,000 mg each time, which is also related to the amount of exercise. Primary fitness enthusiasts must not eat too much when the amount of exercise is relatively small, otherwise eating too much will also cause waste and some uncomfortable reactions. Then don't eat L-carnitine before going to bed, because it will make your body excited and affect your sleep.