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Ripped and Thermogenic To the Core

By: George L. Redmon, Ph.D.N.D.

Several studies have confirmed that humans show significant (mild) cold induced thermogenesis, without shivering. Tissues shown to be involved in adults are skeletal muscle and brown adipose tissue (BAT). The most likely cellular mechanism in both tissues is mitochondrial uncoupling. Recently functional BAT has been rediscovered in adult humans. At the functional level, adipocytes can be subdivided into white and brown. The most important function of white adipocytes is energy storage, while the main function of brown adipocytes is heat production.                           
Wouter Van Marken Lichtenbelt, Ph.D.
Maastricht University, The Netherlands.

Thermogenesis in practical terms centers on the body’s ability to increase energy expenditure above its natural metabolic rate. Dr. Lichtenbelt’s comments above suggest that adult humans have the capacity to induce thermogenesis by increasing the metabolic activity of skeletal muscle and fat tissue researchers refer to as BAT, short for brown adipose tissue. His comments also inform us about the existence of white adipose tissue (WAT) that serves as the main storage reservoirs for triglycerides, simple fats or lipids.

The question that begins to emerge here is how can BAT, as well as WAT tissue for that matter be up-regulated or re-programmed to move an individual beyond their normal thermo-genic or fat-burning potential? Based on research over the last decade or so researchers have discovered the existence of proteins within BAT and WAT tissue known as uncoupling proteins.

Originally uncoupling protein 1 (UCP1) was thought to be the main control switch in BAT that turned on this tissues internal heat pump so to speak. It does so by burning fatty acids from white fat stores. However, researchers have discovered the existence of new uncoupling proteins UCP-2/UCP-3 widely dispersed within muscle, immune and amazingly in white body fat. Comparably, UCP-2 and UCP-3 have similar heat producing effects to UCP-1, however independent of ATP production. Incidentally, mitochondria cells are referred to as the power house or energy factories of the cell where energy is produced and fatty acids are burned. Nonetheless, brown and white adipose tissues have a number of similar abilities such as fat storage and adipokine (cytokines-cell signaling proteins) secreted by adipose (fat) tissue.

As a note here, adipocytokines informs other cells about the energy status of the body and helps them burn fat safely and more efficiently. However, from a physiological standpoint the energy or fat storing white adipose tissue has few mitochondria and a low oxidative capacity. The heat-producing brown adipose tissue on the other hand has a high concentration of mitochondria and a high oxidative capacity, meaning they are more efficient at fat-burning.

Releasing Fat: A Key Pre-Cursor to Thermogenesis

The bottom line here, simply releasing fat stores without being core ready to burn them will only lead to redistribution/redeposit of them. Interestingly, both white and brown adipose tissue lipolysis (the breakdown of fats into fatty acids) are mainly under control by the sympathetic nervous system. Also, as in white fat cells, beta-adrenergic receptor activation in brown fat cells promotes what researchers refer to as adenylate cyclase activation (cAMP production) which increases lipolysis. By the way, the sympathetic nervous system plays a critical role in the regulation of thermogenic responses to cold exposure and dietary intake while catecholamine-stimulated thermogenesis is facilitated by the beta-adrenergic receptors as cited above. Increased sympathetic activity accelerates the secretion of key catecholamine’s epinephrine and norepinephrine. Incidentally, catecholamine pronounced cat·e·chol·amine such as epinephrine, norepinephrine, and dopamine are derived from the amino acid tyrosine, and up-regulate thermogenic processes. Correspondingly, as cited by Dr. Harry Preuss, M.D. at Georgetown University researchers have divided thermo-genic activity into three different categories: exercise-associated thermogenesis, non-exercise activity thermogenesis and diet-induced thermogenesis. Here we will focus on supplemental boosting of non-exercise thermogenesis or your resting metabolic rate (RMR).

Natural Born Thermo-genic Agents

Fortunately, sports medicine researchers have identified several natural supplements that have the capacity to induce thermogenesis. In fact,Dr. Abdul G. Dulloo, Ph.D. at the University of Fribourg in Switzerland states that  although the pharmaceutical approach concentrates on the development of drugs that would target beta3-adrenoreceptors, believed to be the pivotal adrenoreceptors which sympathetically release noradrenaline activating thermogenesis, there is also considerable interest in the nutritional/nutraceutical areas for screening foods and/or dietary ingredients with potential thermogenic properties by virtue of their mode of action by interference with the sympathoadrenal system. What is important to remember in reference to fat-burning is the more efficient you are releasing fat stores, the more you can burn. However, your body must be primed or re-programmed to do so, not only during a workout. Similarly, the supplements cited below have can help you reprogram, heighten and shift your thermogenic potential into overdrive even at rest, essentially generating spontaneous generation of heat during normal catalytic reactions.

Caffeine - recently, researchers at the University of Vienna, in Austria investigated the effect of caffeine on mitochondrial oxidative phosphorylation, cellular energy supply and thermogenesis. They found that caffeine induced a depolarisation (the difference of the charge between the inside and outside of the plasma membrane of a muscle or nerve cell) of the inner mitochondrial membrane within 24 hrs. These researchers remind us that this is a distinct feature of mitochondrial thermogenesis, paralleled by increased concentrations of uncoupling protein-2 (UCP-2) another indication of the thermogenic activity of caffeine. Similarly, in a study appearing in the American  Journal of  Clinical  Nutrition  subjects 90 min before and 240 min after ingestion of placebo, caffeine (10 mg/kg of bodyweight), or caffeine during β-adrenoceptor blockade in post-absorptive conditions (the period following absorption of nutrients) reported that in placebo 34% of lipids were oxidized and 66% were recycled. However, caffeine ingestion increased energy expenditure by 13% and doubled the turnover of lipids, of which 24% were oxidized and 76% were recycled. Also these researchers noted that β-Adrenoceptor blockade decreased. As a note here, Beta-adrenoceptors normally bind to the metabolic activators norepinephrine and epinephrine.
Overall, caffeine appears to increase both lipolysis (the breakdown of fat) and thermogenesis (calorie burning) for a period of time after ingestion.

Forskolin- extracted from the Coleus forskohlii plant, researchers have known for some time that forskolin activates cAMP. For example, researchers of the Sport and Exercise Sciences at the University of Kansas in a randomized, double-blind placebo-controlled study for 12 weeks comparing forskolin to a placebo noted favorable changes in body composition by significantly decreasing body fat percentage, fat mass and increased lean body mass compared to placebo. These researchers also noted significantly increasing bone mass and serum free testosterone levels in these overweight and obese men. Uniquely, the actual change in serum total testosterone concentration was not significantly different among the groups but it increased 16.77 ± 33.77% in the forskolin group compared with a decrease of 1.08 ± 18.35% in the placebo group. Similarly, researchers at the Penn State administered 25 mg of forskolin (250 mg capsules of 10% standardized forskolin extract) to subjects twice daily for eight weeks. At the end of the eight-week trial, the participants lost ten pounds, and reduced their percentage of body fat by nearly 8%.

Green Tea - green tea has two thermogenic components, caffeine and EGCG. Current research suggest that catechin polyphenols like epigallocatechin gallate (EGCG) helps boost circulating norepinephrine which increases the breakdown of stored fat and carbohydrates. Current data indicates that green tea is effective at stimulating thermogenesis by preventing inhibition at different control points along the cyclic adenosine monophosphate (cAMP) axis. As a reminder here, cAMP is formed from ATP responsible for triggering the cellular processes for lipid metabolism, essentially serving as the primary signaling agent that stimulates lipolysis while reducing lipogenesis.

L-Carnitinethis amino acid is synthesized from the amino acids lysine and methionine. L-carnitine while not an active fat-burner as once believed, it is however important in fat metabolism because it acts like a bus and transports fatty acids into the mitochondria. Recently researchers at the University Hospital of Ferrara in Italy reported that Propionyl-L-carnitine a carnitine derivative that has a high affinity for muscular carnitine transferase increases cellular carnitine content, thereby encouraging accelerated free fatty acid transport into the mitochondria. As a note here muscle carnitine palmitoyltransferase II deficiency is a metabolic disorder characterized by an enzymatic defect that prevents long-chain fatty acids from being transported into the mitochondria for utilization as an energy source. It is here that researchers at the University of Texas remind us that fatty acids are the most abundant source of endogenous energy that can be mobilized from surrounding adipose tissue and transported via the blood to active muscle. These researchers state that during low intensity exercise, glycogen (stored glucose)  breakdown and thus glycolysis (the breakdown of glucose to pyruvate with the release of usable energy) is not markedly stimulated, so the increased availability of fatty acids allows their breakdown to serve as the predominant energy source. However, at higher intensity exercise, stimulation of glycogen breakdown and glycolysis cause increased pyruvate entry into the TCA cycle for oxidation, and as a consequence the inhibition of fatty acid breakdown by limiting their transport into the mitochondria.

As a reminder here, the citric acid cycle also known as the tricarboxylic acid cycle, the TCA cycle, or the Krebs cycle is the second of three metabolic pathways that are involved in fuel molecule catabolism and ATP production, the other two being glycolysis and oxidative phosphorylation. During oxidative phosphorylation the mitochondria in cells use their structure, enzymes and energy released by the oxidation (breakdown) of nutrients to reform ATP. However, data indicates that when lipid is infused well in excess of requirements during high-intensity exercise, less than half the energy is derived from fat. This is because the muscle itself is a major site of control of the rate of fat oxidation during exercise. The researchers cited above found that the mechanism of control of fatty acid oxidation in the muscle is the rate of their entry into the mitochondria, hence the major role L-carnitine plays in transporting fatty acids into the mitochondria.

Yohimbe yohimbe bark is an herb derived from a West African yohimbe tree and contains a chemical called yohimbine which can increase blood flow and nerve impulses.It is most often used to treat erectile dysfunction and general sexual problems in both men and women. Current data also indicates that yohimbine can augment the production of the catecholamine’s epinephrine and dopamine. As discussed catecholamines increase the release of fat. In practical terms here, yohimbe increases fatty acid synthesis by preparing stored fat for use as a fuel source while reducing adipogenesis, the creation of new fat. For example, a study appearing in Research in Sports Medicine twenty top-level male soccer players were administered either yohimbine (20mg per day) or a placebo for 21 days.

There were no statistically significant differences between groups in body mass and muscle mass, however, percentages of body fat significantly decreased in the yohimbine group after the supplementation (9.3 +/- 1.1 vs. 7.1 +/- 2.2%). These researchers concluded that yohimbine supplementation appears to be suitable as a fat loss strategy in elite athletes. Uniquely, yohimbe blocks alpha 2 receptors which are much more abundant than beta-1 receptors. Alpha 2 receptors are associated with increasing fat cell production and the storage of fats by inhibiting the release of the fat-mobilizing hormone norepinephrine. The take home message here, yohimbine ensures higher norepinephrine levels, which causes your body to break down fat cells, paralleled by increased blood flow to fat tissue, which causes less fat to be retained.

Thermogenic Agents Galore

While this report can’t cover all of the supplements known to generate thermogenesis, the following list represents some well-known and utilized thermogenic agents that you have at your disposal. By the way sports medicine researchers have begun using these supplements together in various combinations. Although not conclusive some are: Bitter Orange (citrus aurantium), Cardamon, Cayene (capsaicin), Cinnamon, Co-enzyme-Q10 (CoQ10),7-ketoDHEA, Kola Nut, Garcinia Cambogia (Hydroxycitric acid (HCA) , Ginger Root, Guarana , Pyruvate ( pyruvic acid), Raspberry Ketones, Synephrine, Taurine, Theanine, Turmeric, Tyrosine and Yerba Mate.

As a note here researchers recommend supplementing herbs like Ashwaganda, Holy basil and Rhodiola rosea when using thermogenic agents as they stimulate the adrenal glands to release the catecholamine’s epinephrine and nor-epinephrine to release stored body fat. These herbs nourish and supports adrenal function.


Fat is a formidable opponent. When you view this statement  from a scientific point of view, the massive force of fat cells (70 billion) you have to deal with, it‘s easy to understand the formidable task bodybuilders are confronted with,  trying to sustain and maintain an internal state that is attacking fat, rather than mounting counter attacks that are only successful temporarily. You have the ability to take the fight to fat by reprogramming your fat cells to release fat, as well accelerating their transport into what could be referred to as your fat-burning matrix, to decreasing their re-creation and re-distribution. You have at your disposal an arsenal of supplements that can help you burn body-fat on a more continuous basis beyond your workout routine, essentially converting your body into a multi-dimensional fat-burning machine.

About the Author:

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