Peptides and Muscle Growth
Peptides can significantly influence muscle growth by stimulating the release of growth hormone from the pituitary gland. This hormone plays a crucial role in muscle development and recovery. Additionally, certain peptides can increase the production of proteins, which are essential for muscle growth and repair. Therefore, peptides can be a valuable tool for those looking to enhance their muscle growth and athletic performance.
What are peptides doing in my organism?
Peptides play a significant role in our bodies, helping with various biological functions including those in the nervous, endocrine or immune system [1]. They also contribute to the maintenance of homeostasis, inhibition of genetic ageing program and realization and lifespan prolongation [1].
In our organisms, they participate in cell differentiation, growth and development. They can direct the differentiation of meristematic stem cells and also the formation of tissues and organs [2].
In the nervous system, they serve as signalling molecules. They can control muscle contraction or neuronal circuitry [3]. In addition, neuropeptides can influence our cognition as well as learning and memory processes.
Other uses of peptides include peptides for weight loss. Peptides can also affect gut health and the gut microbiome. Peptides are also a promising therapeutic approach for tendon repair.
Can peptides help with muscle growth?
Peptides have been detected to have a significant contribution to muscle growth. According to studies looking at how supplementation of certain types of peptides (e.g. myostatin propeptide, collagen peptides, and novel peptides MIF1 and MIF2) in combination with resistance exercise (for instance strength training) can lead to increases in muscle mass and even strength.
In a study investigating the effects of pea peptides and exercise in male rats, an increased body weight was detected [4]. Further, in another study, supplementation with bioactive collagen peptides was found to enhance the function and structural adaptation of skeletal muscles to resistance training. In addition to these findings, they saw an increased muscle volume in individuals who received the collagen peptide supplementation compared to the placebo group [5].
Interestingly, another study investigating peptides and interaction with growth factors in mice found that viral-mediated delivery of Insulin-like growth factor (IGF) (a hormone) in isoform B promotes muscle hypertrophy only in growing mice. This finding suggests that the bioavailability of the receptor affinity diminishes with age [6]. Therefore it is important to keep in mind that the effectiveness of peptides can vary and is influenced by the individual’s age and also overall health.
How can peptides affect muscle growth?
As abovementioned, peptides can affect muscle growth through interaction with growth factors. In particular, IGF seems to play an important role in muscle development and growth and peptides produced from the IFG1 gene have been reported to promote cell proliferation and are essential for muscle growth [7].
Moreover, collagen peptides seem to enhance muscle mass and strength when combined with resistance exercise training. They found that increased protein composition of skeletal muscle leads to an increase in body mass, fat-free mass and muscle strength [8].
However, let’s not forget to note that muscle growth can be influenced by other factors as well including chronic elevations of growth hormone [9]
Are peptides good for bodybuilding?
So now that we know that peptides indeed can influence muscle growth, are they good for bodybuilding?
Peptides are considered crucial for muscle growth as they are the hydrolysis products of proteins [4].
In a study investigating resistance-trained men, they found that ingestion of specific collagen peptides combined with resistance training resulted in an increase in fat-free mass and a decrease in fat mass compared to a placebo group [10]. Another study looking at elderly men found that collagen peptide supplementation combined with resistance training resulted in an increase in body mass, fat-free mass and muscle strength than resistance training alone [8, 11]
As mentioned above, pea peptide supplementation in conjugation with resistance exercise has also been shown to increase muscle gains and strength [4].
In addition, after-training protein supplementation, including peptides, helps to further enhance muscle mass and strength [8, 11].
However, it's important to note that while peptides can enhance muscle growth and strength, they are also listed in the official World Anti-Doping Agency lists, indicating that they can be used for doping [12]. Therefore, it is crucial to understand the sports regulations and use peptides responsibly.
In conclusion, peptides can be beneficial for bodybuilding, particularly when combined with resistance training. However, one has to be careful when dealing with them so the actions are in accordance with sports regulations. Furthermore, some peptides have received a lot of hype on social media, but the scientific evidence behind their safe usage is missing. For example, the benefits and side effects of BPC 157 in humans have not been studied enough.