Depends on how much muscle you've gained since your running days. It can be done (Alex Viada does triathlons as well as powerlifting) but needs to be worked into gradually if you've gained a lot of weight--joints and tendons not used to having the extra mass bouncing up and down on them can really get irritated and can lead to tendonitis or such. Nothing likely severe but it could really hamper your training.
Overall I would mix cardio tools. You're going to need to do cardio to do a physique contest anyway. A good mix of steady cardio like jogging and higher intensity stuff like sprints or hill sprints or HIIT will work well.
It is a myth that the occasional jog will kill your gains. It often even helps recovery in people accustomed to it. Long periods of cardio constantly every week--sure, those can kill gains. But jogging for 20 minute 2 times a week? Nope