I beg to differ on the "running will injure you" stuff as I think it's profoundly wrong. Running is more likely to highlight any problems you might have stored up as a result of a sedentary lifestyle but there is no higher incidence of knee problems in runners than non-runners. Runners are more likely to visit doctors and physios with knee problems because it stops (or hinders) their running whereas a fat bloke driving a van in London 8 hours a day will have a dodgy knee from heavy clutch work and might not do anything about it for years.
Running is a weight bearing activity which promotes higher bone density. Cycling, being non-weight-bearing, can actually cause osteoporosis and osteoarthritis in men and women who cycle a lot without doing any other activity. For this reason a lot of professional cyclists do at least some running or weight bearing exercise.
I'm a runner and a cyclist and have a lot of problems when running due to achilles and calf pain. These come directly from cycling as the leg never fully extends at any time during a cycle ride so muscles and tendons shorten. This makes any sport requiring full leg extension, such as running, very painful unless the damage is undone by lots and lots of stretching and some physio work.
While I respect peoples' decision not to run for whatever reason, I believe that using their own personal justification of why they've chosen not to run as discouragement to others is unhelpful at best. And the OP is already a runner so the run/don't run thing is not in question here.