I'm reading a thread now from the beginning, the posts I'm reading are from around April 2015, so I don't know about now, but at that point, there were 4 people on the thread that had CX that were very close to one year old and healthy (one CX per person). What they did is feed 2 times a day, and only let them have food for 10-15 minutes before removing it, also, they free ranged them to encourage movement. They ran, jumped, one attempted to fly sometimes, and estimated weights were around 20 pounds and the size of a heritage turkey hen. These birds are the exception more than the rule, but it can be done to get them to laying age and rather large without health issues.