Exercise While at Work Alleviates Work-Related Pain and Improves Mood in Workers

The goal of this clinical trial is to learn if specific exercise protocol while at work works to treat musculoskeletal pain such as neck pain, back pain, or shoulders' pain in adults workers. It will also learn about the effectiveness of this exercise protocol in improving their mood while working. The main questions it aims to answer are: * Does exercise while at work help in alleviating pain due to physical exertion? * Does exercise while at work help in improving mood in workers? Researchers will compare the exercise group to a control group (no guided exercise during the intervention period) to see if exercise works to treat pain due to physical exertion in various working populations. Participants will: * Apply a specific exercise protocol adjusted to their workplace and their job's profile for 2 months with a frequency of 3 times per week * Fill in questionnaires about their pain, mood state, fatigue scale, functional activities level (SF36), Neck disability Index at the beginning of the study, the end of the study and 2 weeks after the end.