When exercising to lose weight, is it better to eat before the workout or exercise without eating? Italian researchers found that fasting before exercise does not increase fat use in the 24 hours After the workout. Eating a small meal prior to exercise resulted in more calories expended during and after exercise.
Carbohydrate stores are greatly diminished after an all-night fast. Carbohydrates are the most important fuels for exercise at intensities above 65 percent of maximum effort. You need carbs to train effectively. When using exercise to promote weight control, eating a small meal before training will improve the quality of the workout and its effect on metabolic rate. (International Journal Sports Nutrition Exercise Metabolism, 21: 48-64, 2011)