Growth factors that participate in the promotion of muscle growth
- IGF-1 is highly anabolic
- Plays a key regulatory role in muscle growth
- IGF-1 stimulates the proliferation of satellite cells.
- Enhances satellite cell fusion and increases cell density
- Insulin promotes the formation of muscular myotubes and enhances differentiation
- Supports muscle protein synthesis
- Insulin promotes blood vessel dilation which improves circulation of nutrients to the injury site
- Increases the amount of muscle glycogen that gets stored in the muscle tissue
- Testosterone has been shown to increase the levels of neurotransmitters at the site
- Â Testosterone stimulates GH secretion and interacts with the receptors in DNA
- Testosterone modulates the activity of the satellite cells by increasing IGF-1 production and the density of androgen receptors
- Growth hormone stimulates the production of IGF-1
- GH plays a key role in the uptake and integration of amino acids into the new muscle proteins
- GH is also believed to promote myogenesis which is the formation of muscle tissue.
Â Bodybuilding peptides :
â€˘ Growth Hormone Stimulating Peptides
â€˘ Growth Hormone Releasing Peptides
High-Intensity Training and its Effect on Muscle Growth
Bodybuilding and weight training will stimulate more contractile protein. Contractile protein will then need further muscle nuclei (myonuclei) to function properly. The inactive stem (or satellite) cells around the muscle fibre then have the ability to be stimulated to fuse with the muscle fibre.
It can then differentiate into myonuclei, and help produce and support the additional contractile proteins. High-intensity training is highly effective at both stimulating increased contractile protein, alongside supplying myonuclei to maintain cellular function. Maintaining the correct GH and testosterone levels also can do this.
How do we increase / gain muscle mass?
In order to increase muscle size and strength there must be improvements made to the neurological control of the muscle cells. This improvement is made by way of the brain and spine. The brain sends signals along the motor pathways communicating to the muscles when, how rapid and powerfully they should contract in order to move..
This neurological control is achieved through the sequence of frequent high-intensity repetitions of a particular movement. Each movement results in changes in nerve connections and activation thresholds.
Muscle growth occurs primarily by the production of extra contractile proteins within the muscle cells, a process called muscle hypertrophy. There is also a small increase in the number of muscle cells, a process called hyperplasia
How muscle growth occurs on the cellular level.
In a matter of hours post workout, white blood cells called neutrophils and macrophages, enter the injured muscle to reduce inflammation on site. Cell signalling proteins called cytokines are also released, which in turn attract more white blood cells and satellite cells.
Upon being signalled, satellite cells wake up from a relatively dormant state to proliferate at the site of the muscular injury. Satellite cells regulate gene expression, and they possess a single nucleus.
The tissue damage prompts cellular replication and differentiation of the satellite cells into mature muscle cells by fusing to the existing muscle fibres. This new muscle protein strand will facilitate muscular repair.
As training continues, satellite cells will continue to heal damaged muscles; flooding injured fibres with satellite cells. The cells will need to become part of the cell cycle in which the replication of molecular pathways takes place.
Signalling pathways ultimately regulate activation and expansion of satellite cells, resulting in the production of bigger, stronger muscles.
The body needs to be in an environment conducive to healing and growth for satellite cell activation.