Will working out after cheek implants cause them to migrate? Am I worrying too much?

Thank you for the question. Generally, I ask my patients to avoid any strenuous activity for 1 week. After this, patients may resume brisk walking or elliptical. I specify that all heavy lifting and contact sports be avoided for at least one month. Take care!

You did not mention how long ago your cheek implants were placed.  It is normally recommended to avoid any strenuous activity for at least a week or two after facial implants are placed and some surgeons may prefer waiting even longer.  If your implants were not placed recently, there should be no problem with working out, as this will not cause the implants to move.  

Soon after surgery you should avoid exercise to
enable swelling to go down are reduce bruising. Typically, I advise my patients
to refrain from exercise for about 3 weeks to be on the safe side.

Although you didn't say how long ago your implants were placed, if you are 4 weeks or so out, the implants are solid.  I have performed this procedure for over 25 years and haven't had an issue with working out and movement of implants.  I do, however, ask my patients not to strenuously exercise for a month.