A repetitive strain injury is damage to your muscles, tendons or nerves caused by repetitive motions and constant use. Repetitive strain injuries are very common and can occur anywhere on the body, but usually affect your fingers and thumbs, wrists, elbows, arms, shoulders and knees.

As their name suggests, repetitive strain injuries are caused by doing the same motion or activity repeatedly until it starts to hurt your body. Any motion or movement — from typing on a computer at work to practicing an instrument — can cause a repetitive strain injury if you do it too often.

The most obvious way a repetitive strain injury will affect you is the pain, discomfort and other symptoms you feel. Common causes of RSI include working out too hard without warming up and cooling down, sports or other activities that require you to use the same motion repeatedly, poor posture when sitting or standing, working with a tool that vibrates, and working in the cold.