Don’t train on an empty stomach. Eat protein, healthy fat and avoid fast-digesting carbs before lifting. If your goal is fat loss, avoid carbs post-workout. If your goal is glycogen replenishment and muscle building, a conservative approach is to consume high simple carbs and protein in a 3:1 or 4:1 ratio within 30 minutes following exercise. This translates to 1.2 to 1.5 g/kg of simple carbs with 0.3 to 0.5 g/kg of a quality protein containing essential amino acids.