Repetitive strain injuries develop primarily from what?

Repetitive strain injuries (RSIs) primarily develop from ongoing work activities that involve repetitive motions, sustained posture, or excessive force over an extended period. These injuries result from the cumulative effects of these actions, leading to strain on muscles, tendons, and nerves. Common examples include conditions like carpal tunnel syndrome, tendinitis, and bursitis, which often arise in work settings where tasks are performed repetitively, such as typing, assembly line work, or frequent lifting.

The other options reflect scenarios that can lead to different types of injuries or issues, but they do not relate to the mechanism behind RSIs. Single traumatic incidents are more associated with sudden injuries, external environmental hazards might cause injuries due to accidents or exposure, and accidental drops or spills typically lead to acute injuries rather than the gradual onset associated with repetitive strain.