I signed up to this a few weeks ago and not really done anything, made feeble attempts, but I only walked and although last week, eg; I walked 3 miles and was worn out, it wasn't a very fast pace. After not doing much all day I said to my husband about going out for a walk, I followed the app and tried to run when prompted, (he walked) but as it was the first time of attempting to do this "properly" when told to run I barely made the first min, by the third I only ran about 30 sec and my walking slowed down after each run. We still walked (and some running) 2.38 miles for 40 mins in total and I was worn out, but felt great!! Im 14 stone and only around 5ft :3' so need to loose at least 4 stone! I hope it gets better as today was pathetic, being out of breath so much with trying to run for one min!!