FATIGUE AFFECTS HUMAN PERFORMANCE
CST (Cumulative Standing Trauma) is the excessive stress on the spine and back muscles due to stagnant body positions or poor distribution of weight, causing pain or even serious injury. Have you ever gone to the beach and noticed how comfortable standing in the sand is? There is a reason for that. Sand gives way and moves away from the maximum pressure points in your feet, resulting in uniform pressure across your foot. This makes standing in the sand a great deal more comfortable than standing on hard surfaces like cement, wood or tile flooring, especially for long periods of time. There is a large body of evidentiary data showing that fatigue affects human performance. Over the past three decades, many studies have shown that mood can be worsened by fatigue, enhancing traits such as anger, anxiety, and confusion.
The National Safety Council, in its publication "Ergonomics", recommends the use of anti-fatigue mats, as do numerous ergonomists, OSHA, industrial hygienists, occupational nurses, risk managers, loss control agents, safety engineers and insurance companies.