I ordered an XL baby play yard from Walmart.com and set it up in the room with my treadmill and put my son and a bunch of his favorite toys in it. It's basically a big plastic fence that you snap together. That way, I could keep an eye on him and there wasn't any danger of him crawling over and trying to touch the treadmill while I was on it. This was when he was not walking yet and couldn't find ways to escape the play yard, so I would probably do this with your 6 month old while the toddler is napping. I am so glad you trying to find a way to keep up your running...it does make for a happier, better mama. You are also teaching your kids the importance of staying fit and healthy My son is now 4 and he likes to "run" with me. On the way back home on a run, I will let him out of the jogger at the end of our street and he "races" me back to our house. On a side note, I have recently started doing the Turbofire DVDs at home as well and love them!! I love running, but the Turbofire workouts mix it up and burn a TON of calories!!