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November 07, 2023
Building muscle is such hard work we need every advantage we can get. Peptides are one such potential advantage. However, a lot of confusion and misinformation is circulating about this subject. Maybe you've heard of peptides for bodybuilding but aren't sure how they work or which ones are the best. In this article, we'll identify the five best peptides for muscle growth, detail the correct dosages, and explain how peptides work for muscle gain.
The five best peptides for muscle growth are:
Peptides are naturally made in the body, but just like testosterone, as we age, their production decreases. Synthetic peptides have been developed to supplement the body's natural production. Here's an overview of the five synthetic peptides that are recognized as most effective for muscle gain.
Ipamorelin is a man-made peptide that is classified as a human growth hormone-releasing peptide (GHRP). It is widely considered to be the best peptide for muscle growth. It stimulates the body to secrete growth hormone from the brain's anterior pituitary gland.
Ipamorelin's specific mode of action is to mimic the hormone ghrelin, which allows it to bind the ghrelin receptors in the pituitary gland. This stimulates the release of growth hormone-releasing hormone, which, in turn, promotes greater GH secretion.¹
Muscle Growth: One of the advantages of Ipamorelin is its selective action. It primarily stimulates the release of GH without significantly affecting other hormones. This selectivity minimizes the risk of side effects associated with some other peptides or growth hormone-releasing compounds. Unlike some other peptides, Ipamorelin does not bring on a stress response.
Increased growth hormone release may increase lean muscle mass potential and enhance muscle repair. Coupling the use of Ipamorelin with weight training will position your body for optimal muscle growth and mass increase.
Fat Loss: Ipamorelin also promotes fat loss. Growth hormone boosts the burning of body fat for energy. This peptide also increases metabolism to reduce body fat. This dual action on muscle growth and fat loss makes it popular among athletes and bodybuilders.
Recovery: As well as promoting muscle growth, Ipamorelin assists with post-workout recovery by promoting tissue repair. It may also improve sleep quality, which is vital for exercise recovery and muscle growth.
Dosage: The recommended dosage of Ipamorelin typically ranges from 200 to 300 micrograms per day, administered through subcutaneous injections. The timing of administration of this peptide for muscle growth is often before bedtime to align with the body's natural GH release pattern during sleep.
Legality: Ipamorelin is not approved for recreational or athletic use in many countries. Its use is usually restricted to medical purposes, such as treating growth hormone deficiencies. In the United States, the FDA has not approved Ipamorelin for human use. It is banned by the World Anti-Doping Agency (WADA) and the United States Anti-Doping Agency (USADA).
Research: Most of the research on Ipamorelin has been conducted on animals. The scientific community considers such research to be 'pre-clinical. In one study on rats, the researchers were interested in seeing how effective Ipamorelin was in reducing bone damage. While they found that the peptide was able to reverse bone damage in the rats, they also noted that it led to significant increases in muscle strength.²
There has been no direct research evidence that Ipamorelin increases muscle mass. The closest we have is a number of rodent studies that showed that rats injected with this peptide were significantly stronger than those not. We can also hypothesize from the fact that WADA bans Ipamorelin and other GH-enhancing peptides that they may have a muscle and strength-enhancing effect.²
CJC-1295 is another Growth Hormone Releasing Hormone (GHRH) peptide. As such, its key benefit is to stimulate the release of growth hormone. Like Ipamorelin, this is a selective action peptide, minimizing any side effects.
Originally, CJC-1295's development was geared towards helping people dealing with excess fat accumulation in the context of HIV/AIDS. However, clinical trials were stopped following an incident in which one participant passed away. Even though researchers concluded that the participant's death was not related to CJC-1295, research on it was largely abandoned.
Different Forms: CJC-1295 is available in various forms, including a version boosted with Drug Affinity Complex (DAC). This addition helps the compound bind to blood proteins, leading to a significantly longer half-life compared to CJC-1295 without DAC. While CJC-1295 DAC boasts a half-life of about one week, its no-DAC counterpart clears from the body within about an hour.
Increased Growth Hormone Levels: CJC-1295 demonstrates its muscle-building promise by significantly elevating blood levels of growth hormone and insulin-like growth factor-1 (IGF-1). These effects lay the foundation for potential muscle growth.
Fat Loss: CJC-1295 may promote fat loss through the release of growth hormone, which boosts fat lipolysis. Increased muscle mass, which is promoted by this peptide, also increases metabolism to burn more calories at rest.
Quality Sleep: The peptide may also contribute to improved sleep quality. Its parent compound, growth hormone-releasing hormone, has been associated with reduced cortisol levels at bedtime, an increase in rapid-eye-movement (REM) sleep, and slow-wave sleep. Quality sleep is crucial to the muscle-building process.
Research: Most of the research into the effects of CJC-1295 has been done on rodents. There are a small number of human trials, but these usually had very small sample populations. One such study looked at its effect on sleep quality. The results showed reduced cortisol levels at the onset of sleep, increased rapid eye movement (REM) during sleep, and increased slow-wave sleep. Interestingly, the peptide was administered intra-nasally.³
No human studies on healthy subjects show increases in muscle mass as a result of taking CJC-1295.
Dosage Considerations: Administered via subcutaneous injections, CJC-1295 is typically dosed between 2000-4000 mcg per week. To ensure safety, it's advisable to begin with a lower dosage and incrementally adjust based on individual needs.
Hexarelin is yet another growth hormone-releasing peptide (GHRP). It operates through the activation of growth factor pathways, particularly those involving phospholipid-dependent protein kinases. This stimulates GH release, which stimulates protein synthesis, creating new muscle tissue.
Fat Reduction: Besides muscle growth, Hexarelin has shown promise in reducing body fat. The heightened GH levels can boost metabolism and promote the use of stored fat for energy.
Cardiovascular and Bone Health: Hexarelin is believed to support cardiovascular health by binding to CD36 receptors found on blood cells. Athletes may also benefit from its potential to strengthen bones and increase joint flexibility.
Cognitive Benefits: Researchers are interested in learning more about the neuroprotective benefits of Hexarelin. A 2022 study suggests that this peptide may be able to reduce brain inflammation, potentially preventing cell damage.⁴
Research: A 2017 rodent study focused on the ability of Hexarelin to prevent muscle loss in cancer patients undergoing chemotherapy. Results showed that the injection of this peptide led to significantly less muscle and strength loss in the group that took Hexarelin. The study authors hypothesized that this was due to improved mitochondrial function, less inflammation, and better regulation of cell turnover, all of which were attributed to the administration of the peptide.⁵
When it comes to Hexarelin and fat loss, a Canadian study is of interest. In this study, researchers treated the white fat cells of rats with Hexarelin to see what effect it would have. They noted that the peptide administration resulted in decreased triglyceride accumulation and higher levels of genes that control fat metabolism.⁶
Recommended Dosage: Hexarelin is taken as an oral injection. The recommended daily dosage typically falls within the range of 200-300 micrograms. Users should start with lower doses and gradually adjust as needed. Cycles typically last 12 to 16 weeks to achieve optimal results.
Sermorelin is another GHRG peptide created to increase growth hormone production in the pituitary gland. This peptide originally received FDA approval for treating growth hormone deficiency. However, in 2008, its approval for commercial use was discontinued, though it remained available as a research chemical. This means that Sermorelin is no longer prescribed as a medication but can be purchased 'for research purposes.'
Muscle-Building Potential: There is research that suggests that Sermorelin can promote some lean muscle mass gains in men who have been diagnosed with hypogonadism. Its beneficial lean muscle mass-building effects on healthy men are less clear.
Enhanced Sleep Quality: Users of Sermorelin have reported improved sleep quality. Adequate sleep is essential for muscle recovery and overall health.
Immune Function and General Well-being: Beyond muscle-building potential, Sermorelin may boost immune function and contribute to overall health and wellness. While its primary focus is on GH release, it may have secondary effects that boost the body's immune response.
Research: A 2020 research paper by Deepanker et al. stated that Sermorelin can significantly improve the body composition of male cancer patients undergoing chemotherapy while also helping to prevent fat gain. There are, as yet, no studies to show the peptide's effects in terms of muscle gain on healthy people.⁷
There is also research indicating that Sermorelin may have anti-aging benefits. In one study, the participants were nine healthy young men. Researchers found that Sermorelin injections could stop age-related decline in growth hormone and IGF-1 levels.⁸
Optimal Dosage: Sermorelin is typically administered in daily doses ranging from 500 to 1000 micrograms, delivered by injections.
GHRP-6 is another ghrelin-mimicking growth hormone-releasing peptide. Increasing ghrelin levels in the body signals the pituitary gland to increase growth hormone release. Users also report that GHRP-6 may also increase energy levels, allowing you to train harder.
The increased GH level brought on by using GHRP-6 stimulates the liver to increase its insulin-like growth factor-1 (IGF-1) production. This hormone helps to burn body fat by increasing fat lipolysis. GHRP-6's six amino acid sequence signals the brain to release growth hormone while not allowing the regulatory hormone somatostatin to prevent that release.
As well as promoting muscle gain through increased GH release and stimulating fat loss, GHRP-6 may also promote better sleep, increase energy levels, and boost immune function.
Dosage Recommendations: GHRP-6 is administered orally. A common dosage is 100 to 150 mcg, one to four times daily.
Peptides are short chains of amino acids consisting of 50 or fewer individual amino acids. Longer amino acid chains are classified as proteins. Peptide bonds join them together.
We classify peptides based on the number of amino acids in their chain:
Peptides perform the following functions in the body:
Research into peptides has led to breakthroughs in medicine, including the development of peptide-based drugs for various diseases.
There are a number of mechanisms through which synthetic peptides may promote muscle growth:
A class of muscle-building peptides called growth hormone secretagogues or Growth Hormone-secreting peptides (GHSPs) stimulates growth hormone release in the pituitary gland. The most effective growth hormone secretagogues are Ipamorelin, GHRP-6, and GHRP-2.
Growth hormone promotes muscle growth by stimulating protein synthesis. This is the process by which muscle is repaired, and new muscle tissue is created in response to the stress of resistance training. GH also stimulates the liver to produce Insulin-Like Growth Factor (IGF-1). This hormone is also a key player in the processes that lead to hypertrophy.
Growth hormone has also been shown to help prevent muscle cells from breaking down, preventing catabolism.
Myostatin is a type of protein that actually works against muscle growth. Some synthetic peptides are designed to block myostatin so that muscle cells can develop without restriction. A prime example of a myostatin-inhibiting peptide is Follistatin.
Some synthetic peptides are designed to improve collagen synthesis. The most abundant protein in the body, collagen, promotes strong, healthy bones, ligaments, and tendons. By strengthening these parts of the body, these peptides indirectly support resistance training gains and muscle growth.
Some synthetic peptides are made to speed up nutrient and oxygen transportation to the muscle cells. This enhances muscle repair and regrowth after a workout.
Specific peptides possess strong anti-inflammatory properties. This helps combat the detrimental muscle cell effects of oxidative stress from intense workouts. These peptides may also reduce inflammation and muscle soreness post-workout.
When used in accordance with prescription guidelines, peptides are generally safe. However, there are some potential adverse side effects to be aware of. Here are some general side effects common to all peptides:
Let's now zoom in on the side effects of the five peptides we are featuring in this article:
The ambiguous answer to this simple question is yes and no. While a number of peptides can only be purchased with a doctor's prescription, many others are legal 'for research purposes only.' That means that you can legally buy them but not actually consume them. That's because they haven't been FDA-approved for humans. That is why online retailers sell peptides clearly marked 'for research purposes only.' Of course, what the purchaser does with the product after purchase is out of the control of the seller.
The form of peptide administration depends on the specific peptide being used. Injection is the most common form. Some peptides, such as BPC-157 and TB-500, are taken orally in capsule or tablet form. Oxytocin and desmopressin are examples of two peptides that are administered nasally in spray form. Others are applied topically in lotion, serum, or lotion form.
No, peptides are not steroids. They are short amino acid chains with specific bodily functions, such as promoting the release of hormones. Steroids are synthetic versions of the hormone testosterone. While they can both support muscle growth and workout recovery, anabolic steroids have a more powerful effect. At the same time, anabolic steroids carry far greater health risks than peptides.
Whether peptides are better than SARMs depends on what your goal is. If it is to build muscle, then the small amount of research suggests that SARMs have an advantage over peptides in hypertrophy. When it comes to fat loss, peptides are more effective because they stimulate the release of growth hormone, which, in turn, stimulates the breakdown of stored fat.⁹
Peptides are a promising supplemental tool for those who are already training hard and eating smart to gain muscle. Remember, though, that they are not a steroid substitute nor guaranteed to pack muscle into your body. As we've seen, the research on healthy humans is very limited.
We know peptides are much safer than other chemical muscle-building avenues. The five best peptides for muscle growth are the HGH promoters Ipamorelin, CJC-1295, Hexarelin, Sermorelin, and GHRP-6. If you decide to experiment with any of them, be sure to stick to the recommended dosage guidelines and get yourself to your doctor if you experience any serious side effects.
Our recommended online peptide supplier is Regenics, which offers a comprehensive service that includes a detailed blood panel, micronutrient testing, and an InBody composition scan. Based on your results, they then develop a plan that serves your unique wellness needs, meets your short-term goals, and improves your long-term health.
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December 08, 2023
December 07, 2023
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