Waht medicine I can use for physical fittness?

Vitamin-Mineral. No supplement really enhances your aerobic fitness. Deficiency of a few vitamins (d, folic acid, maybe a few others) and minerals (iron, some others) are widespread; I urge folks to use a cheap vitamin-mineral supplement, not everone agrees. For muscle bulk, I would encourage you to consider creatine -- not everyone agrees. Shun illegal drugs. Glad you exercise.