Amazon has released the Brittany Runs a Marathon trailer. The upcoming comedy stars Jillian Bell as an overweight woman stuck in a state of arrested development who resolves to take up running and complete the New York City Marathon. I caught the film at Sundance this past January and adored it. In my review, I wrote: As someone who is overweight and horribly out of shape, I could definitely relate to Brittany’s story. No one starts out being able to a marathon. You have to keep pushing yourself a little further every time and you have to maintain the …