Deca is the brand/Trade name for the anabolic steroid Nandrolone. Nandrolone promotes very significant increases in collagen synthesis, more so than most other anabolic steroids. It means that bodybuilders and athletes can experience positive effects on connective and joint tissue, strengthening them during bulking, strength gaining, and mass gaining cycles. It grants them the ability to lift heaver weight with an enhanced recovery of bone and connective tissue. Nandrolone is not a C17-AA oral anabolic steroid, and therefore no effects on the liver exist with this compound.