(Undated)  --  A new report ranks Portland among the U.S. cities considered to be the most physically active.  The report, prepared by BetterDoctor.com, shows Portland at Number Seven, with a score of 70 out of a possible 100.  Rankings are based on health criteria such as physical activity, healthy weight, and access to quality parks.  Seattle ranks fifth in the survey, with Aurora, Colorado, San Francisco, and Oakland occupying the top three spots, respectively.