I guess my question is have you had any reported repetitive injuries? If not, be careful what you do, it might trigger one. You might contact your local medical care facility or rehab center and have them come out and demonstrate the proper exercises. This way the liability is off you in maybe showing them something that might hurt the employees. Also the employees are more likely to watch and listen to an “expert” then one of the bosses. In a previous employment, I had the therapy people that I used, come out and show one of the departments some exercises. The department started doing this daily for about two weeks before it fell apart. We did not force the department employees to participate, but those that chose not to, still had to stand and watch, they could not go off and do what they wanted. We did not enforce them to participate because if they got hurt doing it and they were forced to do it, it would more then likely turn into an OSHA recordable case.
You also want to look at workplace design. If the employees are standing, do they have a mat to stand on? Do they have a place to raise a foot onto, a step so one foot is higher then the other. If they are sitting, can the seats be adjusted to fit the employee to the work place? If lifting, have the employees been shown the proper lifting techniques recently?
To start an exercise program is one step; you might also invest in an ergonomic survey of your work environment.
Perhaps with a little more information about what the employees are doing, we might be able to help more.
Good luck.
Safety Management '82
Indiana State Univ.