Being sedentary is a common cause and start of venous disease in many patients.
Why is leg muscle pump important in vein health?
Blood comes to the legs and other tissues through arteries. The same blood from the legs is returned to heart through veins by two mechanisms
1. leg muscle pump
2. Negative pressure in the right ventricle created by forward blood pumping by heart creating gradient
When you don't move your legs, blood cant be returned to the heart through the veins efficiently. Blood starts to pool in your veins causing them to distend. Fluid starts to ooze through the capillaries when the pressure increases, causing legs to swell.
The more of this happens , the more leg veins distend, making valves functionally incompetent. Over period of time there is inflammation in vein valves, causing permanent damage to the valves. Damage to the valves make them thick, non pliable and non flexible, allowing blood to leak downwards, which leads to pooling of blood in the distended leg veins. The same causes further inflammation in veins.
This leads to a condition called chronic venous insufficiency and also varicose veins.