I train 6 times a week (MA and weight training) and i must take vitamin supplements. There's no way i get all my vitamins from the food. I just can't eat that much. Studies show that only 5% of the Earths' population eat well balanced meals. That includes whole grain, low fat etc foods. I consulted with a nutritionist and she advised me to take multivitamin, vitamin E, calcium and magnesium daily so my body could keep up with my intense training. * Multivitamin: to get all vitamins * Vitamin E: great antioxidant, athletes may consume upto 7 times more oxygen while working out than "normal" people and that produces ALOT of free radicals (oxidants). An increase in stamina and endurance is also attributed to Vitamin E. * Calcium: helps to stimulate the muscles * Magnesium: is used to relax the muscles. It is also needed for cellular metabolism and the production of energy. Speaking of vitamins, i just don't take any vitamin, i only eat natural/whole food ones. There's a big difference in eating a synthetic or natural vitamin. Their molecular structure is different and also the bioavailability, which may differe as much as 90%. For example vitmain E (synthetic) sold in many many stores is called Alpha Tocopherol but actually vitamin E consists of 4 tocopherols (alpha, beta, gamma and delta) and 4 tocotrienols (alpha, beta, gamma and delta). That's why it's important to eat WHOLE FOOD supplements, so you get all the components. Here's some useful links: Synthetic VS Natural Nice database about vitamins, minerals etc Some vitamin supplements Q&A Some insight to vitamin E