How soon can I resume weight lifting after fat transfer to pectoral muscles?

you need to understand that with fat grafting, each fat cell needs to grow its own blood supply to be robust and long lasting. This takes at least 2 weeks and I would probably not advise any heavy pressure for up to a month. Initial capillaries are very tenuous and with enough squeeze from working out with weights, you could squeeze off its blood supply. 

Each plastic surgeon has their own protocol and I would highly recommend you talk to your plastic surgeon and ask what he or she recommends.

Fat transfer it follows the same basic principles as other forms of tissue grafting or tissue transfer.

In order for the tissue to survive a new blood supply needs to be established.

The grafted tissue initially it's kept alive by a process known as plasmatic imbibition followed by neovascularization.

Fancy Latin words for drinking plasma and in the growth of capillaries.

Until neovascularization has been accomplished the grafted tissues should stay immobilized.

This usually happens between the third and 10th say after the procedure.

Even after two weeks the new ingrowth of capillaries are fragile and should be protected. Paragraph I tell my patients to minimize movement for three weeks after which they can engage in full activity.

I tell patients to avoid any form of direct pressure such as massage.

Best,

Mats Hagstrom M.D.