Newsletter
HotBod August 99
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 Tae Bo Myth
Every few years, a new aerobic fad hits the market, claiming to be the "ultimate workout." Step aerobics, cross-country skiing and spin classes have all had their day in the sun as the exercise du jour. While these activities still enjoy a measure of popularity, they have given way to the current rage: cardio kickboxing. Cardio kickboxing has been touted as the fastest to way burn fat, tone muscles and achieve total fitness-quite a claim!
Cardio kickboxing was brought into prominence by a California-based martial artist named Billy Blanks who, through flashy infomercials, turned his Tae-Bo workout into an overnight phenomenon. With a host of celebrity endorsements, Tae Bo developed a cult following, selling millions of videos and turning Blanks into an international star. Seeing the immense popularity of Tae Bo, others began to jump on the bandwagon and kickboxing classes soon turned up in just about every gym in the country.
Cardio kickboxing combines traditional martial arts into an aerobic format. It uses a series of choreographed punches and kicks to elevate the heart rate and maintain a sustained level of caloric expenditure. The workout is very energetic and many find it to be a great deal of fun.
However, despite the hype, cardio kickboxing is not a fitness panacea. Providing exercise is performed at the same relative intensity, aerobic activities are all equally effective at burning similar amounts of fat. Whether it's biking, stair climbing, jogging or any other aerobic modality, there is basically no difference in total calories expended. Thus, if you want to shed bodyfat, cardio kickboxing is no better than traditional forms of aerobics.
Cardio kickboxing also does little to shape and tone your muscles. In order to achieve muscular definition, your muscles need to be taxed beyond their normal capacity. However, since cardio kickboxing is performed at a sub-maximal intensity (as are all aerobic exercises), there isn't enough of a stimulus to force your muscles to adapt. Only by training anaerobically, with short bursts of activity performed at or near muscular capacity, will you generate sufficient muscular overload to sculpt your physique.
In addition, because of the unorthodox movements required, cardio kickboxing has a high incidence of injury. As opposed to machine-based aerobics (i.e. stationary bike, stair climber, etc.), a fair degree of skill is required to execute complicated punching and kicking maneuvers. Pulls, tears and strains can easily develop if proper care isn't taken. An injury can seriously curtail your workout regimen, potentially hampering your ability to train indefinitely.
Does this mean that you should refrain from engaging in cardio kickboxing? Absolutely not! If you enjoy this type of activity, by all means incorporate it into your workout. Just understand its inherent limitations and stay within your means to reduce the prospect of injury.
In final analysis, while cardio kickboxing can be an enjoyable form of exercise, it is by no means your ticket to physique heaven. If you want to maximize your body's potential, it is paramount to have a balanced program that includes both strength and flexibility training, as well as aerobics.
NUTRITION CORNER: Protein Intake
One of the most frequently asked nutritional questions concerns the optimal intake of protein. Which is best: a high protein diet or a low protein diet?
Without question, protein is the king of all nutrients. It provides the building blocks for enzymes and hormones, enables nerve and brain cells to effectively communicate with one another, and fosters the repair and growth of muscle tissue. Every cell in your body contains protein; life could not go on without it.
For anyone involved in regular exercise, protein should account for 35 to 40% of total calories, equating to roughly 1 to 1.25 grams of protein per pound of bodyweight. Hence, a woman weighing 120 pounds needs to consume a minimum of 120 grams of protein per day. Any less and you risk falling into a negative nitrogen balance. Disregard the United States Government's recommended daily allowance (RDA) for protein (an absurdly low 4/10 of a gram per pound of bodyweight). The RDA is based on the needs of sedentary people and doesn't take into account the increased demand required for active individuals.
Make sure that your choice of proteins comes from lean sources. Skinless poultry breast, lean red meats, seafood and egg whites are excellent choices. For convenience, there are a wide variety of protein powders available at health stores and other outlets. Whey protein powders are generally your best choice, followed by egg, casein and vegetable sources.
SUPPLEMENT REVIEW: Branched Chain Amino Acids (BCAAs)
What they are: Branched chain amino acids (BCAAs) are protein compounds. There are three different BCAAs: leucine, isoleucine and valine. BCAAs are essential proteins; they cannot be manufactured by your body and hence must be obtained through your food intake.
What they do: BCAAs help to improve protein synthesis and inhibit the catabolism of muscle tissue. Also, by blunting serotonin production, they can reduce exercise-induced fatigue.
The verdict: Certainly, BCAAs play an important role in dietary functions. However, assuming your protein intake is adequate (at least one gram per pound of bodyweight) and is derived from high quality protein sources, you should be consuming more than enough BCAAs to fuel your body. There is no evidence that megadoses of BCAAs provide any additional benefits. Thus, unless you are on a low protein diet, BCAA supplementation is superfluous.
Supplement Grade: C
