My guys weren't completely grown in height until at least 12-13 months, and definitely much later until their bodies were "mature". Even Corgan still has a teenage look (slowly filling out). I don't usually jog or bike mine until around 14-16 months. Maybe just a very short, slow distance after 6-8 months, to socialize to a bike. I live on dirt roads and forest floor though, so there are no problems with pavement. My trainers will work a GSD or Mal gradually after one year. Is there anyone with a yard in which you could play ball with him offleash? I admire the brave folks that can live with a young CSV in a city environment!