In normal life, blood is returned to the heart from the legs by being pumped back by movement of the legs. The combination of movement and the valves in the veins of the leg is called the Leg Pump.

The most important parts of this leg pump are movement of the ankle (the calf pump) and pressure on the foot (the foot pump).

This Leg Pump is described in detail in the Veins Website.

In the travel situation, movement of the legs is encouraged. This movement of the legs (see diagram on the left) causes a squashing of the deep veins within the muscles, keeping the blood flow in the veins fast (see the diagram on the right).

The speed of the blood in the veins reduces the risks of any clots (DVT's forming).