Malegra 50, containing Sildenafil Citrate, is primarily used to treat erectile dysfunction (ED) in men. It helps by improving blood flow to the penis, thereby facilitating the ability to achieve and maintain an erection during sexual stimulation. However, your query seems to ask about maintaining physical difficulty, which might imply sustaining a challenge or endurance in a physical activity. If this is what you meant, Malegra 50 does not enhance physical endurance or stamina beyond its effects on erectile function.