Reposting as a favor to all of our friends at Chairs Quick (http://chairs-quick.com)
How many times have you heard it from mom when you're sitting at the kitchen table and you lean back in one of your chairs to have only two chair legs touching, and she says, "Four on the floor!" Well there is actually something to that old saying. Safety aside, some in the furniture industry estimate that you will lessen the life of that chair. Some estimate 50-75% of the life a chair is lost when you regularly lean back. Of course the heavier we Americans get the less likely our chairs will hold out like they did for grandma, especially when we jeopardize the structural integrity by leaning back on two legs.