Repetitive strain injury (RSI) occurs in the body when repetitive tasks, exertions and sustaining awkward positions causes injury to the musculoskeletal and nervous system, this can often be occupational. It is most commonly seen in the arms, hands and fingers from using the computer keyboard and mouse. RSI is the term used to describe a number of conditions of the muscles, tendons and soft tissues due to the repetitive use of that part of the body. Unfortunately, RSI is not like a strain from a sudden injury or accident, it is usually a condition which lasts much longer and takes more time to ease the pain. RSI is not to be confused with an overuse injury which is when muscles and tendons are used excessively, ie when running and preparing for a marathon. Unlike RSI, overuse does not involve the constant repetition of the same movement.