This is a tropical fruit and may be a bit expensive at the grocery store or is hard to find. But if you are keen on building your muscles, this must be in your diet plan. Why? Mango is rich in antioxidants and it will inhibit the body from producing free radicals. These free radicals can cause cancer and destroy your cells. By eating mango, you are reducing the occurrence of developing free radicals which will make your cells recover faster after workout.