It's also true that you won't lose fat from your abdominal area just by targeting your abs with crunches or other abdominal exercises. To lose belly fat, you have to reduce your overall body fat. While running can help you lose fat, you'll have a lot more success by combining it with a healthy, low-calorie diet. Like all aerobic exercise, running promotes weight loss throughout the body and is a good option for flattening the stomach. It increases endurance, builds muscle to maintain an optimal body fat composition, promotes cardiovascular health, strengthens the heart, and even improves your overall mood. Combined with weight training, running can help you maintain the perfect balance of mental stimulation and physical fitness.