Is exercise for the core safe 8 weeks post-op?

Thanks for the question. After 6 weeks your surgery area is totally healed and yes you can do exercising and also do other activities.

This is usually normal considering you are still 8 weeks post op. You should expect to have some weakness at the beginning, but with a gradual increase of exercises, you'll get your former strength back. It just takes a bit of time. Start off slowly, stopping as soon as you feel discomfort, and take lots of breaks.  Definitely avoid sit-ups for at least three months but instead start with planks.

Typically I recommend that you refrain from vigorous exercise and strenuous activity for 6 weeks following tummy tuck.  You can usually resume cardiac exercise within a few weeks, but avoid core strengthening exercises in order to allow adequate healing of your abdominal musculature, especially if muscle tightening was performed.  

It is not uncommon to experience discomfort once you return to exercising these areas.  I usually say to slow down or stop if you do have some pains with that activity.  You should be able to slowly resume your exercise at this time.  Certainly, an evaluation by your plastic surgeon should be done prior, so as to examine that you are appropriately healing well and that you are cleared for activities.   Hope that this helps and good luck!