Newsletter
HotBod March 99
Welcome All:Welcome to all the new subscribers to the HotBod newsletter as well as those who have been with us from the beginning. Each month we'll explore issues relating to the three major areas of fitness: exercise, nutrition and supplementation. As always, your comments, questions and suggestions are always appreciated.
TRAINING CORNER: The Stairmaster and Size of Your Butt
There is a prevailing misconception amongst women that the using the stairmaster will promote a big butt. This myth was put forth when a popular magazine suggested that the stairmaster was responsible for increasing the derrieres of exercising women across the country. Afraid that they would soon possess a rear end the size of a movie screen, women began to avoid the stairmaster like the plague. Fortunately, there is not a shred of truth to this myth. In fact, it is virtually impossible to substantially increase muscle mass through the performance of any endurance-related cardiovascular activity. The reason for this is simple: There are two basic types of muscle fibers, slow twitch (Type I) and fast twitch (Type II), and each respond to different stimuli.
Fast twitch fibers are strength-related fibers that contract rapidly but are quick to fatigue. Most of their energy is derived by burning glucose, rather than fat, as a fuel source. These factors make them more sensitive to weight-bearing exercise (push-ups, squats, etc.) where short, intense periods of training are used. In order to accommodate the demands of anaerobic exercise, fast twitch fibers respond by growing larger and stronger. Therefore, they are the only types of fibers that have the ability to increase in size and promote muscular bulk.
Slow twitch fibers, on the other hand, are endurance-oriented fibers that have only a limited ability to increase in size. These fibers get much of their energy by burning fat for fuel, contracting very slowly but having the ability to endure extended periods of activity. Slow twitch fibers are predominantly utilized during the performance of aerobic exercise, with almost no activation of fast twitch fibers. As such, little, if any, muscular growth can take place. Since the stairmaster is aerobic in nature, it stands to reason that it can't contribute to building a substantial amount muscle tissue in any part of the body, including your butt!
NUTRITION CORNER: Sports Bars
Many women are turning to sports bars as a substitute for meal replacements. Since they require no mixing, these bars are even more convenient than a shake. Moreover, a majority of women seem to prefer eating their calories, rather than drinking them.
However, although these products are marketed as a direct alternative to the powdered shakes, they really don't stack up when compared on a nutritional basis. In order to make them more palatable, sports bars are supplemented with a large amount of either fat or sugar. For example, while a Met-Rx shake contains only 3 grams of sugar (14% of total carbohydrates), their comparable sports bar contains a whopping 29 grams (58% of total carbohydrates)! In effect, Met-Rx has turned what is supposed to be a health-based product into a glorified candy bar.
Other sports bars take an alternative approach, employing a higher content of fat (generally 30% or more of total calories) while containing low amounts sugar. Hypothetically, these bars operate on the theory that as long as carbohydrates are kept to a minimum, fat can be consumed more readily without ill effect. Unfortunately, current research has not substantiated this premise and, for most, low fat is preferred.
All told, with the rapid advances in scientific nutrition, it shouldn't be long until someone formulates a better sports bar that is low in both fat and sugar. Until then, powdered shakes are still your best bet.
SUPPLEMENT REVIEW: Chitosan
Chitosan is a new type of weight loss aid called a fat blocker. Derived from shellfish, it works by bonding onto fat and passing it through your system. Thus, fat is supposedly excreted before it can be metabolized by your body.
However, there are several problems with Chitosan. First, Chitosan doesn't reduce the fat already in your body. Second, it only bonds to some of the fat that you consume. Hence, if you overeat large amounts of fat, it won't help you very much. Finally, many of the fat-soluble vitamins (A, D, E and K) stored in your body also pass through your system. This can be detrimental to your health.
In sum, Chitosan has only limited utility. Use it sparingly.
SUPPLEMENT GRADE: C
