Cortisol is considered the enemy of lean muscle mass. The popular theory states that the less cortisol your body produces the better. In fact, chemically assisted bodybuilders lead the way in the battle against cortisol, and many don't hesitate to use dangerous drugs in an attempt to inhibit their natural secretion of the stress hormone. Drug-free bodybuilders also seek ways to suppress their cortisol secretion. The trouble is, the effects of cortisol on the human body aren't all bad. Some of its actions are positive and tend to help build muscle. So instead of looking for ways to block cortisol secretion, you should strive for dynamic cortisol control.
Cortisol and Fat
Fat specialists will tell you that cortisol is a lipolytic hormone, which means it favors fat loss. That's true especially in a test tube—although specialists will also point out that people who are obliged to use synthetic cortisol to treat various illness build up fat at a tremendous rate, even if their diets don't change. It's almost impossible to get rid of the fat gained due to synthetic glucocorticoids, so, if there's a rationale for suppressing cortisol, it's the hormone's effect on adiposity.
The amazing thing is that suppressing cortisol production won't make you any leaner. That's the first paradox of cortisol. An excess of cortisol will make you fat; a lack of it, if anything, will also make you fat.
Cortisol and Catabolism
Most bodybuilders associate cortisol with catabolism, and it's true that studies have shown that animals or sedentary people given cortisol see their muscle mass shrink. Muscle cells contain receptors that bind to cortisol. When that happens, it activates a very strong proteolytic pathway called the ATP-dependent ubiquitin/proteasome pathway, which causes the body to literally eat its own muscles.
The good news is that weight training impairs some of the direct catabolic actions of cortisol. By putting regular tension on your muscles, you prevent the muscle cortisol receptors from working properly. It isn't a complete inhibition, though, because training tends to stimulate cortisol release. That's the second paradox of cortisol: Training both reduces cortisol's direct catabolic impact on muscle and increases the body's secretion of it. The more you train, the less cortisol-based muscle loss you'll experience. Unfortunately, more training also means more cortisol secretion, and the extra cortisol overrides the natural defense exerted by training.
Cortisol and Anabolism
Another nasty effect of cortisol is that it slows the anabolic drive. Part of that anti-anabolic action is mediated directly through the muscle cortisol receptors, and training prevents that. The problem is that another part of cortisol's anti-anabolic action is indirect. Cortisol inhibits the release of numerous anabolic hormones, including growth hormone, insulinlike growth factor 1 and testosterone. It has also been shown to fight the androgen-receptor upregulation induced by nontraumatic workouts.
While training can partially inhibit some of the direct anti-anabolic effects of cortisol by impairing cortisol receptor responses, such preventive effects are localized in the trained muscles only. Training cannot overcome the unwelcome indirect effects of cortisol on the various anabolic hormones.
What About Suppressing Cortisol?
If cortisol can promote protein degradation and at the same time impair protein synthesis, you'd be wise to get rid of it, wouldn't you? There's some scientific basis to that reasoning. Animal-based studies reveal that suppressing cortisol release or inhibiting its actions by blocking cortisol receptors leads to increased muscle mass. For example, there's an amazing Canadian study involving four groups of 10 rats. One group was a control, another was made up of severely burned rats, a third included rats that were burned but also received RU486 (the abortion pill that blocks cortisol receptors), and the fourth was rats that were uninjured and were given the RU486. Which group of rats had the most muscle at the end of the experiment? The rats that were severely burned but received RU486. They had even more muscle than the uninjured RU486 rats. That means RU486 not only eliminates the muscle loss due to stress (in this case a severe burn, although it could have been training), but it also promotes muscle gains. The problem with this study is that rats don't respond to cortisol the same way humans do, so the results won't necessarily apply to people.
Bodybuilders have used this synthetic cortisol receptor blocker without much success, and RU486's failure was attributed to its cortisol-release-stimulating properties. When cortisol receptors are blocked, the body rapidly increases its cortisol production to where the blocking properties of RU486 are overwhelmed. Many attribute the potent muscle building effects of anabolic steroids to their so-called ability to block cortisol. That's unlikely to be true, however, as most, studies have failed to demonstrate a connection between androgens and cortisol receptors. Some so-called enhanced bodybuilders are to pack on muscle even though their cortisol secretion is very high. Furthermore, no studies have noted ultrarapid cortisol elevation after subjects took anabolic steroids, as could be expected with any effective cortisol receptor blocker.
Bodybuilders didn't stop with RU486 in their quest to surpress cortisol. They moved on to drugs that can stop natural cortisol production. With a very low cortisol level, they expected fast muscle growth. What they didn't expect were the strange allergies that some of them experienced.
Cortisol and Protein Absorption
Scientists have known for a long time that eating a meal triggers the release of cortisol. They've also discovered that proteins are the most potent cortisol releasers of the macronutrients. So the more protein you eat, the more cortisol release you trigger. Scientists have now uncovered the pathways used by proteins to induce cortisol secretions, and they've figured out how to block them. It's easy to do. You just block your alpha-1 adrenergic receptors. "That's great!" I hear you say. But don't get too excited yet. Giving alpha-1 blockers to humans before a protein meal blunts cortisol release, but it also blunts protein absorption. The sad-but-true fact is you need cortisol in order to assimilate your dietary proteins properly. It's also a fact that the protein-induced cortisol rise is very short, unlike stress-induced cortisol secretions.
Cortisol as an Anti-Inflammatory Hormone
Not all the effects of cortisol are bad. Some are even helpful to bodybuilders. Weight training induces various degrees of trauma to the muscle fibers, damage that triggers some inflammatory reactions. The more severe the trauma, the more serious the inflammation, which will cause the body to manufacture more of such harmful substances as tumor necrosis factor (TNF). The muscles have TNF receptors, and when a TNF molecule activates a receptor, it activates the ubiquitin/proteasome catabolic pathway. In other words, TNF has an almost direct catabolic effect on muscle cells. Cortisol can inhibit the TNF secretion due to an inflammation, which means that cortisol possesses both catabolic and anti-catabolic properties. If you suppress cortisol release, your body will manufacture more TNF and the catabolic effect of cortisol will be unopposed.
Controlling Cortisol Secretion
Your goal is not to inhibit normal cortisol secretion but to control its secretion and effects. Some drug users have found a radical way of controlling their cortisol secretion: They take synthetic cortisol, and the exogenous glucocorticoids strongly inhibit their natural cortisol secretion. Instead of having fluctuating cortisol levels, they establish an artificial baseline.
It's tricky, but some people have made their best gains while using this method. Of course, if you make a mistake with your dosages, don't expect to pack on muscle. What's more, the technique won't work for natural bodybuilders. Drug users can artificially control their protein turnover rate, a feat natural bodybuilders can't accomplish. We're limited to methods of cortisol control that are more natural but not as precise.
Using a preworkout testosterone booster can moderate the cortisol response to exercise. Testosterone can't completely prevent cortisol's effects, but it can lessen its response to stress.
Growth hormone boosters have the same property. GH can oppose an excessive elevation of cortisol. So can phosphatidylserine (PS). None of the supplements eliminate the stress-induced cortisol elevation; they just keep it within reasonable limits. On the other hand, they don't suppress the basal cortisol release, so they don't cause problems.
Besides stress, there are other ways in which workouts elevate cortisol. If the workout is long, your blood glucose level is likely to fall, leading to hypoglycemia, which triggers cortisol secretion. Taking a carb drink absorbed during training will prevent the fall of blood glucose, countering the hypoglycemia. It will also maintain insulin at a high level, which, as you'll see, is important.
If you choose to fight the exercise-induced cortisol rise, I strongly suggest you use a natural anti-inflammatory supplement such as omega 3s, a group of essential fatty acids derived from fish oil. The omega 3 fatty acids have been shown to inhibit the elevation of catabolic substances such as inflammation-induced TNF.
Controlling Cortisol's Effects
Using both a GH booster and a testosterone booster offers another advantage. As mentioned above, cortisol tends to depress CU, IGF-1 and testosterone secretions, but the natural boosters fight those effects. The carb-drink-induced elevation of insulin also tempers some of the harmful effects of cortisol. For example, insulin is one of the few hormones that can combat the cortisol-induced elevation of the ubiquitin/proteasome proteolytic pathway.
In addition, cortisol stimulates the manufacture and release of glutamine, which empties the muscle glutamine reserves. Glutamine can be formed from other muscle amino acids thanks to an enzyme called glutamine synthetase. Whenever the enzyme activity is stimulated, the muscles start to lose their amino acids. The bottom line is, when muscle glutamine levels are low, anabolism is reduced. Cortisol increases glutamine synthetase expression from the muscles. By taking oral glutamine, you blunt that effect, as glutamine represses the enzyme's activity.
I cannot stress enough the importance of glutamine. When muscle glutamine is low—for example, because cortisol is high—the activity of the glutamine synthetase goes into action, which leads to a vicious circle. Cortisol reduces muscle glutamine a little, but a lower-than-normal muscle glutamine level automatically triggers even more glutamine synthetase expression, which in turn further reduces muscle glutamine levels.
Of course, in the very short run glutamine synthetase increases muscle glutamine levels; however, the newly formed glutamine is rapidly exported from the muscles. In theory, glutamine is very effective at putting an end to the vicious circle. In practice, the entry of the glutamine from the blood into the muscle is not as important as we might hope. Consequently, taking oral glutamine only reduces some of the wasting effects of cortisol although in theory it can potentially blunt them completely.
Muscle branched-chain amino acid (BCAA) reserves are also negatively affected by cortisol, which increases the activity of another muscle enzyme called branched-chain keto dehydrogenase (BCKAD). The effects of BCKAD are very different from those of glutamine synthetase. While the latter manufactures glutamine, BCKAD destroys BCAAs; and while glutamine tames glutamine synthetase activity, BCAAs activate BCKAD.
The rationale for using oral BCAAs is that cortisol reduces muscle-BCAA levels. Even if a portion of the oral BCAAs is wasted because they activate BCKAD, another portion replaces the cortisol-induced loss of BCAAs. So, unlike what happens with glutamine, the oral BCAAs don't directly combat cortisol's wasting effects. Rather, they repair some of the damage it causes.
Using Cortisol's Effects
Although high cortisol levels tend to waste muscle mass, studies have demonstrated that the muscles play catchup when cortisol levels return to normal. A day of rest acts as a brake on the ramped-up cortisol production, making it a powerful anabolic inducer. The lack of stress creates an anabolic overshoot. You need to take regular rest days to ensure muscle growth.
by Michael Gündill