I love being in shape. Running an eight-minute mile, benching 300, riding a mountain bike on rugged trails, playing a rousing game of three-on-three, are all things I would love to be doing. But I can't do any of them today.

Yeah, I am a firm believer in fitness; it just doesn't seem too crazy about me.

In fact, I am currently typing this little essay with one hand and wondering what my next fitness fad should be? In the '70s and '80s I was quite the runner, doing everything from 5Ks to a marathon. Finally, an orthopedist pronounced my knees shot and that my running days were over.

So I got into lifting. I saw my lifts go higher and higher even as my age did too. It turns out strength stays with us well into our higher years, but with a catch...you have to keep at it. You can't store exercise and exercise is the only way to create fitness.

Maintaining fitness is tougher than raising fish. You have to keep feeding it and, if you feed it too much, it dies. Well, it doesn't actually die; it kicks back, like a mule.

The other day I was just doing my usual chest workout and was fully warmed up...I was toasty I was so warm and then "SNAP!" There was pain so severe I was in shock in two minutes...sweating, trying to faint, the whole enchilada. I had pulled my left pec off my arm and had a weird lump on my chest.

So here I am, all trussed up, having gone through a three-hour surgery and planning what to do next to stay in shape. Yes, I get it; 53-year-olds shouldn't be doing one-repetition maximums with more than 300 pounds.

Lesson learned. But I'm not going to let it stop me. I have spent my entire adult life trying to maintain my body with masochistic activity. My first training position was as a fitness and officer survival trainer, and it is one of my deepest beliefs that we must always train our minds and bodies.

If we train right, we achieve that state we like to call fitness, a state of well-being that seems so darn hard to maintain with our lifestyle. Fitness is so selfish; it demands time, effort, patience, and balance...little of which we seem to have.

So we cut corners. We try to work out a bunch today so when we miss the next two workouts we won't lose anything. Then we injure ourselves. But we keep coming back...we have to.

I challenge you to find the things in life you can do to maintain your level of fitness that match the most important things about you. First, find what fits your body type. If you look in the mirror and see a linebacker, don't train like a running back. All you are going to do is find yourself hurt.

Second, accept that time is against us all...we are going to age (if we stay lucky), and we need to adjust our routines to match these limitations. The real key here is to be sensitive to your physical changes and just work around them. I am not going to stop lifting but I am not doing maxes anymore and in just a few minutes I am going for a walk...yep, a wimpy old walk. Why? Because I must feed that burning need called "fitness."

Dave Smith is the creator of the "Buck Savage" series and a former law enforcement officer from Arizona. Currently, he is the lead instructor for Calibre Press' Street Survival seminar.