Why do abdominal muscles disappear when the stomach relaxes

The disappearance of abdominal muscles as soon as the stomach relaxes is mainly related to factors such as high body fat percentage, insufficient abdominal muscle thickness, and core muscle relaxation. The manifestation of abdominal muscles requires a combination of low body fat percentage and sufficient muscle mass.

1. High body fat percentage

When subcutaneous fat covers muscles, even abdominal muscles will be covered by the fat layer. Male body fat percentage needs to be reduced to below 15%, and female body fat percentage needs to be reduced to below 20% in order to show abdominal muscle contours. Weight loss needs to be achieved through a calorie deficit, and it is recommended to combine aerobic exercise with dietary control to avoid excessive dieting and muscle loss.

2. Insufficient thickness of abdominal muscles

The muscle mass of rectus abdominis directly affects the clarity of appearance. Lack of targeted training can lead to weak muscle fibers, which are more easily covered by fat in a relaxed state. Resistance training such as abdominal roll and hanging leg lift can increase the cross-sectional area of abdominal muscles, while plank support can improve muscle endurance. It is recommended to perform 3-4 specialized training sessions per week.

3. Core muscle relaxation

Deep muscle groups such as the transverse abdominis are like natural waistbands, and insufficient tension can lead to anterior protrusion of abdominal organs. Long term sitting and poor postpartum recovery can easily cause core relaxation. Vacuum abdominal training, dead worm movements, and other movements can activate deep muscle groups, and when combined with abdominal breathing, can improve abdominal tightness.

4. Effects of water and diet

Water and sodium retention caused by high salt diet will cause abdominal edema, and excessive intake of alcohol and refined carbohydrates will also promote visceral fat accumulation. Adequate daily water intake, controlling sodium intake within a reasonable range, increasing dietary fiber and high-quality protein intake can help maintain a flat abdomen.

5. Posture and Breathing Patterns

Poor posture such as pelvic tilt can cause passive abdominal protrusion, and chest breathing patterns can weaken the participation of abdominal muscles. Pay attention to maintaining a neutral standing posture in daily life, enhance the coordination between the diaphragm and abdominal muscles through abdominal breathing training, and use cushions to support the lumbar spine during prolonged sitting to reduce compensatory relaxation of the abdomen. Maintaining clear abdominal muscles requires long-term multidimensional management. In addition to regular resistance training such as abdominal rolls and Russian rotations, sufficient aerobic exercise time should be ensured every week. Adopt a balanced diet of high protein, moderate carbohydrates, and low fat to avoid overeating at night. Simultaneously focusing on stress management and sleep quality, elevated cortisol levels may promote abdominal fat accumulation. Postpartum women are advised to gradually resume core training under the guidance of a doctor and avoid blindly engaging in high-intensity abdominal exercises. If the body fat percentage has reached the standard but the abdominal muscles are still not visible, there may be a separation of the rectus abdominis muscle, which requires professional rehabilitation evaluation.