Who knows more about your health? You or your doctor? Think about that for a minute. You know your body. You know how much sleep you need to function the next day. You know what meals keep you full and what foods make you ill. You know how far you can push yourself when you're up against a deadline. The depth of knowledge you have about your own body and the way it "feels" is virtually impossible for a medical professional to get.

What doctors know about you are typically the results of some tests, a few questions and observations made over 10 to 15 minutes, if you're lucky. They know your blood pressure, how well your reflexes work and perhaps your numbers on a blood panel. How can such a quick overview compare to your depth of personal knowledge?

The reality is, both you and your doctor know a lot about your health, but you both approach it from different viewpoints. It's like comparing a pilot and an airplane mechanic.

Just like the pilot, you're the person in charge. You control where you go, what your body's going to do and how you want to react. When your body hits a little turbulence, you're the one who makes adjustments to smooth out the flight. But that knowledge only gets you so far.

Let's say you're preparing for a flight and a little red "check engine" light comes on. As the pilot, there are certain things you do to take care of the problem. You go through your checklist and try to make adjustments so the light goes out. But if it persists, you need to bring in the expert.

Like your doctor, the airplane mechanic will run some tests, ask a few questions and generally be able to pinpoint the specific reason the "check engine" light is on. That knowledge of the "inner workings" of the equipment is what they use to treat the problem.

So what does this have to do with working out? You need to think of your personal trainer as a pilot instructor. We're here to show you how to maximize what you can do with your body, just as a pilot instructor teaches how to best handle and control a plane. Our goal is to help you improve, without inflicting damage.

The way a good personal trainer handles that situation is with a medical questionnaire. Through a couple of quick tests, some observations and appropriate questions, a well-designed questionnaire can help a trainer see if your body has a "check engine" light on or not. If it does, the trainer should require that you get clearance before you start.

It may be nothing. In fact, after dealing with hundreds of clients over the years, most of the time it is nothing. That's the ideal. But there have been some extraordinary cases where I had to get a medical release for a client and it turned out to be a life-threatening issue.

I could have ignored it, taken the money and pressed ahead. In fact, many trainers do. Unfortunately a trainer who thinks they can ignore a "check engine" light on their client is concerned about one thing: your money. Your health will always rank below your wallet.

If you're curious what sort of information is covered on one of those medical questionnaires (or if you're a trainer and you'd like to use ours), we've posted it on www.WeBeFit.com. You're welcome to download it and read or use it with clients.

The way it works is simple. If a client says yes to one or more questions from the first section, or two or more questions from the second section, you have a get-a-doctor's-release.

Remember, if you have to get a release, that doesn't mean you shouldn't work out. It just means a doctor should take a second look at you, because your "check engine" light is on. If your doctor says it's not a problem, get into the gym and start making things better.

Caution: Before beginning any diet or exercise program, check with your doctor first. For a free consultation with a trainer, call 305-296-3434. More articles are online at www.WeBeFit.com.