The authors of “Exercise Physiology: Energy, Nutrition and Human Performance” write that achieving a flat tummy involves a healthy diet combined with a variety of different exercise types.The more you vary your exercise routine, the more you challenge abdominal muscles to work and strengthen themselves in new ways. Different methods of exercise for gain a flat tummy include yoga, cardiovascular training and strength training.YogaYoga is most known for its effects on flexibility and mental calmness. A common misconception is that you need a high level of flexibility to practice yoga — in fact, the flexibility comes as a byproduct of yoga, and increases as you further your practice.Yoga is also beneficial in strengthening muscles, especially your core, which is composed of the abdominal and lower back muscles. The majority of yoga poses require you to use your core to stabilize your torso, and allow the muscles to contract and strengthen during your session.Yoga burns calories and fat; you can vary it according to your fitness level, and it can be as gentle or as intense as you choose in your pursuit of a strong, flat tummy.?Cardiovascular ExerciseCardiovascular or aerobic exercise is one of the most popular and oldest forms of exercise. It is known for its fat and calorie-burning effects; there are many types of cardio you can perform. You can vary your routine to include running, biking and exercising on an elliptical or stair machine. Each type of cardio exercise works different muscles and allows the heart and lungs to build endurance and get stronger.Getting a flat tummy means burning excess fat from the stomach, which happens through regular and consistent cardio. “You absolutely need to do cardio if you’re looking for a flat tummy,” said American College of Sports Medicine-certified personal trainer Shelby Young. “It’s going to burn fat and get you prepared to strengthen the muscles of the tummy.”Strength TrainingStrength or resistance training builds the muscles and strengthens them to get a flat tummy. Exercises like crunches, planks and moves using a large stability ball are all effective in flattening the tummy and developing lean, toned abdominal muscle.You should do abdominal strength training at least three times per week in conjunction with yoga and cardio exercise. The three combined will drop fat and tone the existing muscle while building more core strength. A strong core means better posture, which also makes the tummy look flat when you are walking or standing.“There’s no way you can get a flat tummy without working it through resistance training,” says Young. “It’s the only way you’re going to build that muscle and give it that flat, toned appearance.”