Athletic performance isnot the same as physical health.

Some supplement manufacturers would like their customers to think otherwise. Patients now often ask about "pre-workout" supplements, wondering whether they are safe and effective. These products are marketed to enhance workouts not only with greater energy and stamina, but also for better results such as bigger, bulkier muscles.

General Nutrition Corporation, better known as GNC, is a major vendor of pre-workout products. During the health food rush of the ’60s, GNC’s stores catered primarily to the wellness market. As competition mounted, GNC moved increasingly toward performance-focused products.

Last weekend, I spoke with a manager at one of the Hawaii stores who said workout products are now 60 percent of total sales. The market continues to grow. According to the Nutritional Business Journal, global supplement sales were $32 billion last year and are expected to reach $60 billion within the next eight years.

What is in pre-workout supplements? The majority are powders that contain some type of fuel, usually a combination of protein and carbohydrates with vitamins and minerals. Simple enough. Despite dramatic packaging and promises to enhance performance, a large number of products stop there. They may be safe but do not necessarily deliver.

Pre-workout products may also contain pro-hormones which are designed to increase the body’s natural hormone levels. This is totally inappropriate for a young, growing body. Even for a middle-age person going through meno- or mano­pause, management of hormone levels should be done in a medical setting in conjunction with laboratory testing to ensure targeted blood levels are achieved and maintained.

Stimulants are also commonly included in pre-workout ingredients. They range from caffeine to guarana (also containing caffeine) to green tea extract. Another stimulant — 1, 3-dimethylamylamine, or DMAA — sometimes used was just recalled by the Food and Drug Administration because it can cause elevated blood pressure and heart problems. The FDA has ruled that DMAA is not a dietary ingredient and thus does not comply with the Dietary Supplement Health and Education Act.

DSHEA is a piece of landmark legislation. While on the integrative-medicine lecture circuit in the early 1990s, I spoke with the attorney who drafted the document and got it passed. DSHEA, unique to the U.S., successfully pulls dietary supplements outside the purview of the FDA essentially categorizing them as foods rather than medicines.

The recent FDA recall of products containing DMAA is reminiscent of the demise of Metabolife International following the FDA ban on the sale of ephedra-containing dietary supplements in 2004. Its best-selling supplement, Metabolife 356, had generated hundreds of millions of dollars in annual sales before serious adverse events, including accidental deaths, came to light.

Approximately one year prior, its owners contacted my consulting firm, Global Advisory Services, seeking to sell the company on the international market. I organized a meeting between Metabolife principals and a publicly traded company from Singapore that was interested in putting together a consortium with Singapore’s government to do the deal. However, in the process, reports of adverse reactions caused sales to plummet, and when the FDA banned the sale of ephedra, the suitors lost all interest.

Caveat emptor (buyer beware): Just because a product is sold in a retail "health" store doesn’t mean it is safe. Read ingredients thoroughly and be sure to understand how they affect the body and their benefits and risks. Remember, what may be safe for one person might be dangerous to the next. So much depends on age, general organ health and conditioning, relative weight and the presence or absence of cardiovascular illness or diabetes.

Many of these supplements are fine in moderation especially with adequate hydration, but be sure you are purchasing more than simple proteins and carbohydrates with an expensive label.

The key is a person’s motivation. Go for genuine wellness. Athletic performance should not be won at the expense of one’s health. It’s never worth the price you pay.