From the get go, that sluggish and tired feeling that you get on any given day may not just be due to the fact that you may lack a little sleep. Our bodies are likened to machines. It needs to be well-oiled for it to function properly. That means that your body needs the right kind of fuel if you want it to perform at a top level. This means that your body requires a proper balance of chemicals – vitamins and nutrients, for you to function properly. This essential balance that your body needs is further magnified among people that are required to be in the best physical or cognitive fitness. Think of Olympic athletes, can you imagine them pulling off superhuman feats if they did not have their required calorie intake and nutritional requirements? Perhaps not. On the opposite end of the spectrum, it may also be very hard to concentrate or study for medical and law students and the sheer volume of readings they have to make if they do not get the right amount of nutrition for their brains to work properly. If you want to perform properly, you can start by taking multivitamins that contain the daily minimum requirements for vitamins and minerals that your body needs to achieve that perfect chemical balance. If you want to feel like you are brimming full of energy, you might want to jack up your intake of vitamin B6, B12, and B-complex as well. These are the things responsible for you feeling robust.