Gertrude, left, and Mabel

You don't just wake up one morning and feel old.

Aging is more like a growing sensation that something is slightly amiss.

It's like when the transmission in your car begins to slip and you try to ignore it at first. Then you change the transmission fluid and hope for the best, but deep down inside you know.

Last week, my 60-year-old gears started slipping.

My wife and sister were out of town, so I had some extra chores. My sister asked if I would walk her two dogs, Mabel and Gertrude, and I said yes. I'm a dog lover, and dogs love me back.

So, at about 7 p.m. last Saturday, I drove the four miles to my sister's house and put "the girls" on leashes for their daily stroll.

I should mention that Mabel and Gertrude are Great Danes, and that together they weigh about as much as a University of Alabama nose tackle. Walking them is not really "dog walking" in the normal sense, but more like leading Seabiscuit and Secretariat around Churchill Downs. If they decide to break and run, there is nothing much you can do about it except to hang on for dear life.

Walking them at dusk turned out to be a really bad idea. That's apparently when every other dog owner in Signal Mountain's Old Town neighborhood take their pooches out. Also, it's when the squirrels come out to play.

Mabel and Gertie are both gentle souls, but like all dogs they get excited. They instinctively want to run and greet "new friends" — or, in the case of squirrels, to eviscerate them. This can be disconcerting for other dog owners who only see two giant animals moving toward their pets and barking like the Hounds of Hades.

I realized quickly that I had picked a bad time.

"Now you see why I walk them at 2 o'clock in the afternoon?" my sister would explain later.

At every turn, there was another dog walker or squirrel. I executed a series of klutzy about-faces — a throwback to my band-nerd days — and eventually made it back to the house without giving anyone grounds for a lawsuit. Still, the girls had jerked me around so much that both of my arms felt like they had grown about an inch.

After a good night's sleep, I tackled some heavy-duty housecleaning on Sunday.

Like I had seen my wife do, I unhooked the hose from our upright vacuum and tried to clean the baseboard in the bathroom. But I got the hose too close to the toilet-paper dispenser and — OMG — you will not believe what happened next.

Our Consumer Reports top-rated Kenmore upright vacuum cleaner started sucking in toilet paper at the rate of 32 feet per second. It was one of the most amazing things I've ever seen. The toilet-paper roll was spinning — zing — like a fishing reel hooked to a runaway swordfish.

I caught myself watching the show for a second before reaching out to karate chop the TP chain. In doing so, I lost my balance and stumbled forward, banging my right temple onto the corner of our medicine cabinet.

Not only did I see stars, I saw the entire galaxies.

I almost punched the medicine cabinet, which would have been a spectacularly stupid thing to do since it would have meant putting my fist through a mirror.

Instead, I sat down in the middle of the bathroom floor to rest, regroup and massage my throbbing head.

After getting my wits back, I decided my blood sugar might be low, so I went to the kitchen to pour myself a bowl of Trix cereal. It was a brand new box of Trix, and I accidentally opened it upside down — silly rabbit.

They don't tell you that the plastic sack that holds the cereal inside the box is triple-glued on the bottom. Thus, anyone who tries to open the sack upside down must exert superhuman pulling pressure. Then, when the sack finally explodes under all this pressure, it recreates the Big Bang Theory, spewing Trix pellets all over the kitchen.

Next, your dog — in this case our boy, Boise — will go crazy wolfing down as many of the little multicolored sugar balls as possible.

Oh my. Getting old is exhausting.

I think I might need a nap.

Contact Mark Kennedy at mkennedy@timesfree or 423-757-6645.