It looks elegant to drink wine with your pinky out, but if you run with your pinkies out, as some runners do, your elbows tend to flare out, which will cause tension in your neck. Also, don’t bounce (too much energy being expended and too much pressure on knees and ankles), lean forward (you’ll go faster) and keep those pinkies in.
Photo: me running at Mission Bay, San Diego, CA (USA)