The coat of the Chow dog is so thick that just brushing it out thoroughly will take hours. Brushing out the Chow's coat properly means brushing out sections of the coat from root to tip of hair shaft. This process is done in sections. Because it is a long process, Chow dogs are taught to lay down on their sides quietly during the brushing.
Start having your Chow Chow pup lay down on its side while young while you brush its coat. It takes patience and time to get them use to the idea of laying on their side while you brush every inch of their coat.
At the same time you need to give yourself a break in the grooming process as just the brushing will take a toll on your wrists. Often owner will brush out a 1/4 of their dog's coat at each grooming session, breaking it up over a series of days rather than just devoting one day to the complete brush out process. That gives both dog and owner a break.