A reader and friend called this week and complained that her old dog does nothing except sleep and eat. "He barely moves," was the way she described him. I asked how old he was - and his breed - and discovered that he was eight years old and of a moderately large, but normally active breed. I recommended that he have a medical physical (since he hadn't had one in over a year) and that she ask to have his thyroid levels checked.
Barring a medical problem (an inactive thyroid can be treated with pills) an 8-year-old dog should not be as lethargic as this owner states. Could he be bored?
A dog that is healthy should continue enjoying the activities he participated in previously. As long as your dog enjoys doing the things you have always done with it, whether it be hiking, backpacking, visiting shut-ins, or participating in obedience fun matches, there is no reason to stop doing it just because you turned the calendar page. You might have to take shorter hikes, lighten the load usually carried in the backpack, visit fewer people per day or enter only one show every month or two as your dog ages, but as long as there are the normal signs of excitement when you pull out the equipment, don't stop having fun with your dog.