When walking, the interaction of muscles and veins creates the venous pump, forcing blood back to the heart from the legs. Gravity causes blood to settle in the feet and leg when standing for long periods due to the decreased effectiveness of the venous pump. In the short term, workers get aching legs due to increased pressure on the walls of the veins. Over the long term, this pressure can lead to swelling, pain and potentially permanent circulatory damage in these extremities.
Anti-fatigue mats should be considered for assembly tasks that require operators to stand in one place for long periods of time. Standing on a mat stimulates muscle activity in the feet and legs to aid the venous pump. "Not only the material but the surface design stimulates muscle activity in the lower extremities," explains Torsten Rodbroe, president of Ergomat (Westlake, OH), a manufacturer of anti-fatigue mats.