To lose bodyfat, you must decrease your intake of dietary fat. Fat contains more than two times the calories per gram of either protein or carbohydrate. In addition, the body uses fewer calories to metabolize fat. The net effect is that fat is the most fattening nutrient. Some research even shows that your waistline is a direct reflection of your fat intake.
A relevant question is, What's the best percentage of dietary fat intake for effective bodyfat loss? Most bodybuilders who have low bodyfat levels stay on lower-fat diets year-round, although they decrease fat intake before a contest. A typical precontest bodybuilding diet contains 5 to 10 percent fat, which is the same level of fat intake recommended by people such as the late Nathan Pritikin for preventing cardiovascular disease.
The problems with these diets involve both palatability and satiety value. Extreme lowfat diets, in which 10 percent or less of the calories come from fat, are difficult for most people to stick with. For many, eating fat is the only way they can satisfy their appetites. What makes this even more challenging is that when obese people are dieting, their fat cells send out chemical signals to the appetite center in their brains, causing a type of fat hunger.
Is it really necessary to go on an extremely low-fat diet to lose bodyfat? Researchers from Brigham Young University in Provo, Utah, were curious about this. To find the optimum level of fat intake for fat loss, they put 48 obese young women on 1,200-calorie-a-day diets that varied only in fat content. The percentage of protein was 20 percent on all the diets, but fat varied between 10, 20, 30 and 40 percent of total calories. The women also exercised five days a week throughout the 12-week length of the study.
The results showed no differences in bodyfat loss among the groups. This indicates that for effective weight loss, you must pay attention to your total daily caloric intake. It's still a matter of consuming fewer calories than you burn.
Burning Fat at Rest
Fat only burns in the presence of oxygen, which explains why aerobic exercise is best for oxidizing, or burning, fat. At rest most people burn equal percentages of sugar and fat, but as they get more aerobically fit, do they burn more fat even when they're at rest? Even under optimal conditions, humans burn only 30 to 60 percent of the fatty acids released into their blood, with the remainder going right back into storage in fat cells.
A new study from the University of Vermont explored this question. It involved 14 women and 12 men between the ages of 18 and 29. The subjects were divided into aerobically fit and sedentary groups, and the researchers tested the subjects' fat-burning capacity 48 hours after an exercise session.
The results showed that the sedentary group had a higher rate of fat delivery than the fit group when at rest, but the researchers also found that fit people burn fat at the same rate that unfit people do. Since this study measured the appearance of fat in the blood, fit people may simply incorporate the released fat into their muscles faster. Recent research, for example, indicates that the muscle tissue of fit people shows an increased uptake of fat not explained by more fat circulating in the blood. The mechanism is thought to be an increase of a cell membrane fatty acid-binding protein in muscle.
In simple terms, this means that unfit people release more fat at rest, but fit people are more effective fat burners.
Taurine: New Ergogenic Aid?
You may have read about taurine, an amino acid that some people are promoting for increasing anabolic effects in muscle. Up until recently, the greatest publicity generated about taurine involved its being required in feline diets. For humans, the findings concerning beneficial effects of taurine are less impressive. This is probably because tanrine is a sulfur-containing amino acid that the body can make as long as a sufficient quantity of the amino acid cysteine is present.
The journal Amino Acids recently reported a German study involving a taurine-based product called Red Bull. Besides taurine, Red Bull also contains caffeine and a glucose-lactate compound. In the study 10 endurance athletes consumed three different versions of the drink, some without the added taurine.
The results showed that the group drinking Red Bull original, with the three active ingredients showed significantly lower heart rates within 15 minutes of exercise, as well as a decreased release of stress hormones called catacholamines. The most impressive finding, however, was that the taurine group showed increased muscular endurance. The researchers concluded that by helping to modulate stress responses during exercise, taurine may increase endurance.
This is not to be confused with the beer called Red Dog. Attempting to use Red Dog beer as an ergogenic aid will simply leave you barking up the wrong tree.