Go to any vitamin store or leaf through a fitness magazine and you’ll find plenty of pills to boost your workout, drinks to rev up your energy and powders to build muscle.

In 2011, the market for sports nutrition supplements was more than $3.5 billion and that market is growing at more than 10 percent a year, according to the Nutrition Business Journal.

“It’s a huge industry,” says Anthony Musto, Ph.D., who provides sports nutrition education for UHealth Sports Medicine and the athletic program at the University of Miami. “And staying on top of what’s the hot supplement is like trying to stay on top of computer games or video games. Every day there’s something new.”

Another problem when considering taking supplements is that much of what’s on offer isn’t backed by scientific peer-reviewed research. And, to make matters worse, the industry is not regulated as long as there are no health claims made for the products.

“It’s buyer beware,” Musto says. “If you can find a nutrient in food, why not kill two birds with one stone? Eat and get what you need versus going out and paying for a supplement.”

To understand how supplements might help your workout you need to understand the muscles they are designed to bulk up. Joseph Signorile, Ph.D., a professor in the Department of Kinesiology and Sports Sciences at the University of Miami, suggests you think about muscle fibers as individual hairs. Much as you’d pull the hairs into a pony tail, the muscle fibers are bundled together to form muscles.

If you exercise, there are mechanical and biochemical messages that tell the muscle fibers to make more protein and grow larger. The muscles get thicker — a process called hypertrophy.

Whether you are an aging baby boomer, a bodybuilder lifting for a title or a runner competing in the ING Miami Marathon, consider what your body needs to build muscle.

First, there must be a stimulus such as an exercise program that convinces your muscles they need to grow bigger and stronger.

“No matter what you eat, unless you have an appropriate exercise program your muscles won’t adapt and grow,” Musto says.

Second, your muscles need to recover between periods of exercise so that they can adapt and become bigger and stronger.

Finally, you need to eat a diet that provides your body with what it requires to make and fuel its muscles.

“Once you’ve got these under control, then you can consider supplements,” Musto says.

Here are some popular supplements:

Protein: One of the most widely used supplements is protein or amino acid powders or drinks. You’ll find a variety including beef, whey, egg and soy proteins.

“For people seriously into bodybuilding, I recommend a protein supplement,” says Joseph Gatz, an exercise physiologist at the Zachariah Family Wellness Pavilion at Holy Cross Hospital in Fort Lauderdale.

The daily recommendation for the average adult is 0.8 grams of protein per 2.2 pounds of weight (1 kilogram).

A marathon runner needs 1.5 grams of protein per 2.2 pounds of body weight. And a person in an intensive bodybuilding program needs from 1.2 to 2 grams of protein per kilogram of body weight.

Some even go as high as 4 grams of protein, Gatz says.