*THIS BLOG POST IS UNDER CONSTRUCTION - BARE WITH!*
Venous return refers to the blood flow back to the heart. When your venous return in your legs is impaired, often secondary to a reduction in mobility, your legs can become swollen. Typically the swelling is squashy and does not 'pit' when you press into it. If you have 'pitting oedema' (swelling that takes some time to return to 'normal' when you push on it, or will adopt the shape of whatever surface it is leaning against, for example, this indicates a potentially bigger problem such as heart failure or kidney dysfunction and you should speak to your GP to arrange further investigations).
For the purposes of this blog post, we will just discuss poor venous return in the legs relating to lack of usage of the muscle 'pump' in the calf, which sends blood back up to the heart.
What leads to lack of usage of the muscle pump? Mostly inactivity. If you are stuck in a chair due to poor mobility, pain, or even pure idleness (!) your calf muscles are not being utilised and therefore will weaken over time, impeding their ability to pump blood against gravity back up your leg. Blood and tissue fluid pools in your lower limbs, leading to swollen legs.