Depending on your cats age and breed, the cat should be of a standard size and weight. Anything extra above that may mean that your cat is too heavy around the waste. Cats are normally frisky little critters and can easily maneuver their habitat. If you see your cat looking lumpy and slow moving it could be possible that you have over fed your cat and the poor animal is walking around with much more weight than it can manage. One of the problems with over feeding animals is that an animal will not know if it is getting too fat to frolic and hence will simply eat anytime feed is placed inside it's feeding bowl. As a pet owner, it is your responsibility to ensure that you do not over feed your cat and provide the animal with the right diet to keep him living a long and most importantly healthy life. Some cat owners will just shrug it off and say "come on, what can a little more food do?" Well that constant little more food can make your cat develop health issues due to obesity.
Health Risk of Overfeeding Cat
Develop diseases
The human body is not far in anatomy from our animal cousins, cats, dogs, and other mammals. When a cat gets obese it will eventually suffer from the same problems as a obese human would. The cat will develop, liver disease, cancer, heart and kidney problems. In these cases, prevention is always better than cure and feeding your cat more weight conscious diet is a best practice from start.
Can't Groom Properly
Cats are self grooming and spend lots of hours licking clean all areas of their bodies. With an obese cat, the animal would find it very difficult to reach important areas to groom due to fat accumulating in places which should have little to no fat.
The Cat Becomes Unhappy
Remember that cats are agile and many times love to prowl, jump, scratch and do all sorts of "catly" things. If the animal finds these things difficult to accomplish how it used to it will eventually fall into depression and that again may lead to other health issues.
Now, I am sure that you as a cat owner whom loves his/her cat would not want to abuse the animal by simply overfeeding. Give your cat the right amount of feed each day. Limit the feed to 2-3 times daily, depending on the amount and type of food. Do not feed your cat more than three times daily and do not over flow the bowl with food. There are cat bowls available with the maximum amount of food that should be filled for a large adult cat. So you may not have to worry about over filling.