I've done two cycles with Nandrolone. Both times my mobility saw a marked improvement within weeks of starting and lasted for many months after my last injection.
Each time I used Nandrolone however it was accompanied by Test Cyp and Proviron. I can honestly say the feeling I have on Nandrolone is like that of sitting in a hot tub for 20 minutes and then getting out and rubbing some blue heat on our joints. Because I feel so flexible and limber I tend to push myself harder during lifting which in turns lends itself to making better and bigger gains.
I've never used Nandrolone as a stand-alone product and never would. The suppression talk and apparent evidence is too paramount to ignore.
As to the OP. Dosage recommendations have usually been 2mg's a week per lb. Thus a 200lb dude would take 400mg's a week. When I first took Nandrolne though I ran 300mg's once a week; paired with 500mg's of Cyp per week as well as a Proviron a day. At 300mg's a week I realized all the benefits mentioned above but did not seem to suffer any significant libido effects at this dosage and with the Test and Proviron.