Dangers of playing on a treadmill. The boys had been begging for me to put the treadmill down so they could race cars on it. That's what they were suppose to be doing. That lasted all of 2 seconds. They decided to walk on it, but as animals. Diego has a thing for walking on all fours like a dog. Well he turned the treadmill up a little too high and when he went to go on all fours his hand went out from under him and he rolled to the end of the treadmill. Bad thing was that it backed to the wall and he got pinned between the wall and the treadmill. His face got rubbed raw along with a spot on his knee. It freaked him out. Thankfully that was as bad as it got. It could have been so much worse.