When we think of blood pooling, we usually think of the legs—but the abdomen is also a major blood reservoir, holding roughly 20–30% of the body’s blood volume.
When you stand, gravity can pull more blood into the abdomen and lower body. For people with POTS or orthostatic intolerance, this can reduce blood returning to the heart, so the body may compensate by raising heart rate and contribute to symptoms like brain fog, dizziness, fatigue, and heavy legs.
That’s why waist and abdominal compression can matter. Gentle compression around the abdomen may help reduce blood pooling and support blood return toward the heart, helping the body maintain circulation more efficiently.
Sources:
• Common Syndromes of Orthostatic Intolerance — supports 25–30% of blood volume in the abdominal/splanchnic circulation and blood shifting downward when standing.
• Postural Tachycardia Syndrome (POTS) Review — supports abdominal/lower-body pooling, reduced blood return, and increased heart rate.
• POTS: Diagnosis and Management Review — supports common symptoms including dizziness, fatigue, brain fog, and venous pooling.