One thing that is cool about running/walking is that if a street is good for running then more than likely it is good for cycling. I like to call it a "canary in the coal mine" scenario. If walkers and runners of all ages are present, then cyclists should be too.
Bike lanes actually help pedestrians walk or run on sidewalks because they provide an extra buffer from passing cars on the street. They also provide an area for runners to run on the street, but pedestrian and cyclist conflicts are always a problem, so both modes of transportation have to be cognizant of one another.
This is just another reason for municipalities to invest in bicycle facilities. They help runners, cars, and of course cyclists to all work harmoniously. It's beautiful outside today so let's go ride! Ride on!