The goal of most bodybuilders’the great ones anyway’is to get lean. In fact, the goal of most people who work out is to lose bodyfat and finally reveal their six-pack. The questions are, How do you lose bodyfat fast? What are the top fat-burning supplements? And what is the best way to maximize cardiovascular work to optimize fat burning while sparing muscle mass? To understand this complex topic, you should know how the body burns fat and uses it as fuel.
First of all, fat contains nine calories per gram, which makes it the most energy-dense macronutrient. In other words, burning one gram of fat for fuel provides more energy than burning a gram of carbohydrate. Obesity, or greater fat storage, usually results from a continuous imbalance between energy intake and energy expenditure.1 So the key to fat loss is lowering energy intake and/or increasing energy expenditure.
Fatty acids are stored as triglycerides in adipose tissue. Each triglyceride molecule consists of three fatty acids and one glycerol unit. Fats are oxidized, or burned, to provide energy through a process called beta-oxidation, a.k.a. lipolysis. When blood sugar levels are low, especially during longer periods between meals, your pancreas secretes the hormone glucagon and that stimulates adipose lipase activity to release fatty acids from triglycerides.
Epinephrine, or adrenaline, can stimulate the same activity to release energy during the stress response. Once the fatty acids are released, they travel through the blood to other body tissues such as muscle, where they’re oxidized to provide energy through the mitochondrial beta-oxidation pathway. Basically, fatty acids are converted to acetyl-CoA in the process and can then provide energy by entering the Krebs cycle. Another destination of acetyl-CoA is the liver, where it’s used to produce ketone bodies that provide energy to tissues like the heart and brain. That process may increase thermogenesis, or the production of heat by metabolic processes, leading to fat loss.
Cardiovascular exercise can help mobilize fatty acid stores for use as fuel. Moderate aerobic activity seems to burn more fat, although more intense cardio for the same duration may enable you to burn more fat for several hours after the exercise is complete. The best time to do cardio is first thing in the morning on an empty stomach. That’s when insulin levels are low and glucagon is higher, both of which help prime the body for fat use and, therefore, loss. Be sure to drink plenty of water, and you may also want to use a thermogenic supplement beforehand to speed up the fat-burning process. Waiting an hour after the cardio to eat can also spur greater fat burning.
The human body contains different types of adipose tissue. The majority of stored fat in the body is white adipose tissue (white fat); however, the more interesting type is brown adipose tissue (BAT), which actually fights fat by using up metabolic energy to create heat.2
One way to stimulate fat loss is by activating beta-adrenergic receptors’mainly beta-1s and beta-2s, but the beta-3 receptors also show great potential for fat loss. Beta-3 agonists help target BAT, and what’s even more interesting is the fact that they’re only found in fat. Beta-1 and beta-2 receptors are found in other parts of the body, including the heart. Scientists have discovered that in humans the beta-3 receptors exist in great abundance in the thermogenic brown fat cells, especially in the abdominal region. Do you see where this is leading? The theory is that stimulating the beta-3 receptors may help reduce abdominal fat. BAT can also be found between the shoulder blades. (The next time you do cardio, touch the area between your shoulder blades and see if you’re producing extra heat there.)
Many of BAT’s heat-producing effects are due to the expression of uncoupling protein-1 (UCP-1) gene.3 UCP-1 is exclusively found in the mitochondria of brown fat cells.
Other factors affecting fat loss include the thermic effect of food, which is the cost of metabolizing different types of food. Research indicates that a high-protein/lowfat meal boosts postmeal thermogenesis by 100 percent over what you get with a high-carbohydrate/lowfat meal.4 That’s one reason high-protein diets are popular for weight loss. Certain hormones’like thyroid, cortisol, growth hormone and testosterone’can also have an effect on fat burning.
Ephedrine and caffeine. These two powerful ingredients are found together in many fat-loss products. They constitute a power-packed synergistic combination that’s backed by a lot of research showing that it works effectively to help reduce bodyfat fast.5 Many of the studies used a 10-to-1 caffeine-to-ephedrine ratio (i.e., 20 milligrams of ephedrine with 200 milligrams of caffeine), but other studies used different combinations. Caffeine and ephedrine are also found in their herbal forms as guarana, or kola nut, and mahuang, respectively, and the combo offers many benefits besides burning fat and increasing calorie expenditure. It can also help preserve lean muscle mass when you’re restricting calories and suppress appetite, which may be one of its most powerful effects. That’s why so many bodybuilders use the combination before a contest.
Some recent research indicates that ephedrine can enhance anaerobic exercise performance like weight training, psychologically and physically’good news for bodybuilders looking for a preworkout boost. Ephedrine, or ephedra, is a beta-adrenergic agonist that stimulates beta receptors, which can activate the fat-loss process, as discussed above. There are beta receptors on your heart as well, so some people may experience an increased heart rate while using ephedra-based products. That’s why ephedra-and-caffeine products aren’t for everyone, especially people who are on medication or who have heart or blood pressure problems.
Some research shows that taking ephedra daily actually reduces its stimulating effects over time while still increasing energy expenditure and weight loss.6 In other words, people develop a tolerance to its stimulation effects, but the fat-loss effects continue going strong.
Ephedra is considered a nonselective sympathomimetic, which means it may mimic some of the effects of epinephrine and norepinephrine, leading to greater fat burning. Many studies have shown ephedra to be quite safe’including ones conducted at Columbia and Harvard’and millions of Americans have used it regularly and safely. It’s abuse of this potent ingredient that causes problems in some individuals.
So ephedra and caffeine help turn calories into heat instead of storing them as fat, and the combo has also been shown to increase both aerobic and anaerobic exercise performance.7 Caffeine, which is chemically a methylxanthine, is one of the best researched ergogenic aids available today. Several studies have shown that it promotes fat oxidation and both weight and fat loss in exercising individuals.8,9 Many studies repeatedly show that caffeine enhances both short-term and long-term endurance performance.10,11 Caffeine seems to delay fatigue, or prolong time to exhaustion, so aerobic workouts can go on longer and stronger.12
It’s also proven effective in increasing speed in simulated race conditions and in a regular laboratory setting. A study published in the International Journal of Sports Medicine in 1998 states, ‘Caffeine ingestion can be an effective ergogenic aid for short-term, supramaximal running performance.’13 Even though there are far fewer studies documenting the effects of caffeine on resistance training, some evidence does suggest that caffeine can increase the power generated during repeated muscle contractions and enhance endurance at submaximal tension.14 More power equals more reps and, as a result, muscle gains.
Caffeine works through several mechanisms, including promoting the release of stored fat to be used as energy and stimulating more release of calcium from the sarcoplasmic reticulum, leading to greater muscle contraction. It’s also involved in antagonism of the adenosine receptors, mainly in the central nervous system; inhibition of phosphodiesterases, leading to an increased level of cyclic AMP (adenosine monophosphate) in muscle tissue, which creates a more favorable intracellular environment in active muscle; and sparing glycogen, the carbohydrate stores in muscle cells and the liver, because of an increased rate of fat oxidation. That last point could explain why caffeine delays time to exhaustion during aerobic exercise.
Another thing to look out for is caffeine’s effects on blood sugar. Although the research isn’t clear, it may decrease insulin sensitivity, so diabetics need to be careful. Regularly taking in high doses of caffeine may also adversely affect blood pressure. Moderation is the key. A regular cup of coffee has about 100 milligrams of caffeine, but some research shows that coffee is not as effective at maximizing the benefits of caffeine as pure caffeine, taken in pill, powder or liquid form.8
For people seeking fat loss, taking 20 milligrams of ephedrine (standardized from mahuang) and 200 milligrams of caffeine one to two times daily may help accelerate the fat-burning process. The best time to take the combination is 30 minutes before aerobic exercise, preferably first thing in the morning on an empty stomach with plenty of water. You can take an additional dose 30 minutes before lunch. Taking the combo on an empty stomach increases the speed at which the compounds are transported into the bloodstream, while taking it with food may cause nausea in some people. Try starting with half the recommended dose, and after building a tolerance, boost your intake to the full recommended dose. After 12 weeks of continuous use it’s a good idea to take three to four weeks off.
To keep the stimulating effects of this potent combination going, try using it on a two-days-on/one-day-off regimen. Warning: The NFL, NCAA and IOC have banned ephedrine. Also, don’t take it too late in the evening unless you plan to stay up all night, as it causes sleeplessness in most people. Due to the skyrocketing liability-insurance rates for companies carrying ephedra-based products, many firms are switching to potent ephedra-free versions that include synephrine.
Synephrine. Citrus aurantium (bitter orange, or zhi shi) contains the active ingredient synephrine. (It also contains other potent compounds like octopamine and tyramine.) It’s touted as an ephedra alternative and known as ephedrine’s calmer chemical cousin’and it still has beta-agonistic fat-burning effects while being less stimulating to the central nervous system. Doses similar to those used with ephedrine may be effective (20 milligrams of active synephrine after standardization per serving).
There’s definitely more research on ephedrine and caffeine combinations for fat loss, but one study published in Current Therapeutic Research in 1999 showed that a combination of Citrus aurantium extract, caffeine and Saint-John’s-wort caused significant bodyfat loss in overweight healthy adults.15 Other research has looked at the thermogenic properties of compounds found in Citrus aurantium, including synephrine, and the results are very encouraging.
Green tea extract. This powerful supplement is known for its immuno-enhancing and antioxidant effects. The major components of interest in green tea extract are the polyphenols (including EGCG’epigallocatechin gallate) and caffeine. Some research suggests that this potent extract has greater antioxidant protection than vitamins C and E.
What many people don’t know, however, is that it may have potential as a fat burner. A study published in the American Journal of Clinical Nutrition showed that green tea extract actually increased 24-hour energy expenditure and fat oxidation in humans.16 Many experts might say that’s due to its caffeine content, since caffeine has been shown to have some of those properties; however, the authors of the study concluded that ‘green tea extract has thermogenic properties and promotes fat oxidation beyond that explained by its caffeine content per se.’ Green tea extract may play a role in the control of body composition via sympathetic activation of thermogenesis, fat oxidation or both.’
I believe green tea’s thermogenic property is most likely linked to its EGCG content. Another recent study showed the synergy of green tea extracts catechin-polyphenol and caffeine contents, discussing how it stimulates BAT thermogenesis.17 The study mentions that green tea extract and the synergistic relationship of its contents may be a valuable tool in assisting in the management of obesity. Taking 200 to 300 milligrams daily could be beneficial. Look for a standardized extract containing at least 40 percent EGCG.
Coleus forskohlii (forskolin). Although not a stimulant, forskolin is showing up in many thermogenic weight-loss formulas. Coleus forskohlii is a so-called power herb that increases the amount of cyclic AMP in cells by activating an enzyme called adenylate cyclase. Why is it important to increase cAMP levels? There are several benefits to athletes, including relaxation of the arteries and smooth muscles; lower blood pressure; enhanced insulin secretion, which can help drive carbohydrates and protein into muscle cells for energy and recovery; increased thyroid hormone function, which can help enhance metabolic rate; and significantly increased fat burning.
Forskolin also seems to benefit other cellular enzymes. It has been shown to enhance lipolysis, and it may also inhibit fat storage.18 It’s actually patented under U.S. patent 5,804,596 by the Sabinsa Corporation for stimulating lean body mass (the more lean muscle mass you have, the more calories you will burn at rest). A good dose is 100 milligrams of Coleus forskohlii standardized to 20 percent forskolin. Taking 25 to 60 milligrams daily in divided doses can be beneficial.
Guggulsterones/ guggulipid. Thyroid hormones are very important for normal growth and development, and they can enhance fat burning. The two main thyroid hormones that have any relevance are T4 (thyroxine), which is inactive thyroid, and T3 (3,5,3′ triiodothyronine), which is active thyroid. T4 can be converted into T3 in the liver by the enzyme 5′ deiodinase, which in turn can help maintain a healthy metabolism and may cause fat loss to occur.
Guggulipid, also known as guggulsterones, has been used for hundreds of years in India. Several research studies on the herb showed very positive benefits. One showed that guggulipid had a very strong effect in decreasing triglycerides as well as LDL (bad cholesterol) levels while increasing HDL (good cholesterol) levels in human subjects.19 It has these effects because it may cause an increase in both T4 and T3.
Several other studies have shown similar effects of guggulipid as a fat-reducing compound.20,21 Many people following a diet and training program over a fairly long period of time complain that they just cannot lose that last bit of fat no matter what they do. Thyroid hormones may play a key role in getting past fat-loss plateaus. Your body adapts to any calorie deficit by reducing thyroid hormone output. Taking guggul can cause thyroid hormones to become normalized, and you can continue burning fat. Plus, some research suggests that it may even help reduce acne’a nice bonus.
This natural compound has also been shown to be very safe and completely nontoxic in humans. When choosing a guggulipid product, make sure it’s a standardized guggulsterone of type E and Z from the plant Commiphora mukul. A good dose is 25 milligrams of active guggulsterones after standardization taken three times a day. Taking one dose with plenty of water 30 minutes before cardiovascular exercise can be helpful.
Cayenne pepper powder. Cayenne pepper has some unique metabolic and thermogenic properties thanks to capsaicin, its active ingredient. Cayenne’s effects on thermogenesis are mainly attributed to capsaicin’s activation of the sympathetic nervous system’stimulation of epinephrine and norepinephrine. That results in enhanced energy metabolism, more calories being used and a feeling of warmth.22 According to other research, cayenne pepper can also help decrease appetite. When looking for a cayenne pepper product, make sure it contains a standardized amount of capsaicin. A good dose is 30 milligrams three times a day.
Naringin. This flavonoid compound found in grapefruit is what gives that fruit its characteristic bitter flavor. Naringin has recently begun appearing in fat-loss formulas, mainly to increase the effects of the caffeine they contain. It can increase the half-life, lowering the clearance rate of some supplements by interfering with enzymatic activity in the intestines. One caution: Avoid using this ingredient with prescription medicines, as it can prolong their effects. A good dose is 100 milligrams taken two to three times a day with caffeine-containing products.
Octopamine. This unique and interesting compound appears to have great potential for fat loss. It’s actually one of the components of zhi shi, a Chinese herb that comes from the immature dried fruit of Citrus aurantium. When harvested early in its ripening, zhi shi is composed of a number of chemical amines, including synephrine, octopamine, hordenine, N-methyltyramine and tyramine. A study published in January 2000 concluded that ‘octopamine could be considered as an endogenous selective beta-3 adrenergic agonist.’23 That means it could have great potential for fat loss in humans, even though the beta-3 receptor seems to be a newer and less clear area of research.
Some scientists think that the beta-3 receptor is the most powerful and has the greatest fat-burning, muscle-sparing effects when stimulated. The beta-3 receptor is only found in fat tissue, not the heart, so taking a beta-3 agonist may be much less stimulating to the body than taking a beta-1 or beta-2 agonist. Only further research will tell if this ingredient is for real.
The quest for fat loss will never end as long as six-packs’abs, not beer’are in style. Remember, it takes a solid combination of proper nutrition and hard training capped with proper supplementation to reduce bodyfat permanently. Using some of the cutting-edge compounds discussed here can help you get faster results from your fat-loss program; however, it’s important to consult a physician before using any powerful fat-burning agent.
Editor’s note: Rehan Jalali is president of the Supplement Research Foundation (www.tsrf.com). He’s studied the science, efficacy and safety of sports supplements for more than 10 years and is a nationally recognized biochemist and sports nutritionist who consults with many professional athletes and sports teams. Jalali is also an industry-recognized product formulator and natural bodybuilder. To contact him, send e-mail to [email protected].
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