"My idea of a sports bar is a good old fashioned chocolate bar - sure tastes better to me than any sports bar I've tried!"

Powerbars, PR Bars, Gatorbars. You can spend a fortune on these pre-wrapped bundles of energy. Are they worth it? Some athletes swear yes, others claim no. To help you decide on the role of sports bars in your diet, here are some facts to add to your knowledge about your personal taste preferences, food tolerances and budget.

• In today's eat-and-run society where meals are a rare occurrence in a busy schedule, a sports bar suits the need for many hungry athletes who seek a hassle free, somewhat nutritious snack. Compact and light weight, these vitamin-enriched bars are very convenient for runners who want to carry a durable snack on a long run, hikers who want a light backpack, or simply snackers who want to tuck non-perishable food into a pocket. You could also chose low-fat granola / breakfast bars from the supermarket as an acceptable alternative at a fraction of the price.

• Sports bars promote pre-exercise eating - a great way to boost stamina and endurance. This contrasts to the "don't eat before you exercise" myth that has been perpetuated through generations of athletes, and has perhaps limited performance. The energy boost associated with eating a pre-exercise sports bar is unlikely due to magic ingredients (chromium, amino acids), but rather to eating 200 to 300 calories. These calories (generally from some form of sugar) clearly fuel you better than zero calories in no pre-exercise snack. Note that calories from tried-and-true fig newtons, graham crackers, bananas and bagels are also effective pre-exercise energizers.

• Most sports bars claim to be highly digestible. One could debate if sports bars are easier to digest than standard food, because digestibility varies greatly from athlete to athlete. I've heard some people comment about how a Powerbar settles like lead for them, while others swear it is the only food they can tolerate during exercise. As with all sports snacks, you have to learn through trail and error during training what foods work for your system, and what foods don't. Do not try this pricey treat before a special event, such as a marathon, bike race or rugby game, only to discover it causes discomfort. (One key to tolerating sports bars is to drink plenty of water along with the bar. Otherwise, the product will settle poorly. Sports bars have a very low water content which makes them more compact than snacks such as fresh fruit, for example, with a high water content.)

Some sports bars tout they are fat-free or very low in fat, hence digest quickly and empty from the stomach without causing problems. But others boast about a higher fat content that supposedly promotes greater fat-burning to help you exercise longer before you "hit the wall." To date, I know of no peer-reviewed, published research which suggests that pre-exercise fat improves performance. In fact, at the 1994 American College of Sports Medicine convention, researchers reported no difference in "fat-burning" in athletes who are high fat or high carb pre-exercise meals. To date, the bulk of evidence still supports the use of carbohydrates as the main fuel for athletes. Every athlete, fat or thin, has more than enough body fat to supply fat for fuel. Also note that burning fat differs from losing fat-weight. You have to burn fat and maintain a calorie deficit for the entire day to lose fat.

One possible advantage to including a little fat in the pre-exercise snack may be for sustained energy. Because fat takes longer to digest than does carbohydrates, bars that contain fat might be a better energy source for long distance bikers, runners or cross-country skiers who will be exercising for more than 90 minutes. This will vary according to their ability to tolerate and comfortably digest the fat. Alternatively, you can maintain energy by consuming about 60 grams carbs (240 calories) during endurance exercise, rather than by eating fats beforehand.

Sports bars are expensive. You'll have to fork over at least one dollar, if not two, to buy most sports bars. The best value is to buy low-fat granola bars or breakfast bars from the supermarket, rather than sports bars from the specialty stores or health food centers. A handful of raisins can also do a great job at a very low price!