Nothing is more satisfying after workout congestion or pumping the working muscle. This lets you know you’ve done a good job in your workout. Sometimes the worked muscle is so “pumped” that even a slight movement is challenging and can “literally” feel the blood running through your arteries.

The fact that our muscles tend to feel full during the series of higher volume and after workouts is not a coincidence. A busy and congested muscle is an anabolic muscle and an increase in the volume of muscle cells indirectly works as an engine for muscle growth.2

It is generally assumed that the best way to increase the volume of cells is great pumping in the gym. The volume of cells and pumping although interrelated, are not the same thing. Whereas the volume of cells refers to the actual volume of water within the muscle cells, a bulge or reactive hyperemia, physiologically refers to an increase in volume in areas between and around muscle cells also called the “interstitialarea”

Despite this distinction, receiving congestion may, in appropriate circumstances, facilitate increased cell volume. The volume of the cells is critical for the amino acids into the cell, activating protein synthesis and suppression of protein degradation during critical times: before, during, and after training.

The anatomy of a pump and muscular cells

In response to high-intensity exercise, it increases vasodilatation having increased blood flow, this increases the supply of oxygen and nutrients and removing waste products in the muscle worked. This reactive hyperemia, resulting in an increased blood plasma in areas (in-between and around) the muscle cells (interstitial space).

The combination of increased plasma and blood lactate accumulation and other metabolites increase the osmolarity of the interstitial fluid. This creates a concentration gradient that pulls extra blood to water, creating the phenomenon we all know as well as “pumping”.

It increases the concentration of solute on one side of a semi-permeable membrane; the gradient will spread when you add water. This concentration would last until the system reaches equilibrium. Similarly, when the muscle tissue undergoes pumping, increased interstitial fluid osmolarity which attracts water to diffuse out of the muscle cells, which effectively reduce the cell volume.

Fortunately, skeletal muscle is very well equipped and prepared to deal with this. Through a process known as regulatory volume increase (RVI), the muscle cells are able to maintain or even increase the volume of the cell, despite the increase in extracellular osmolarity that occurs during muscle pumps.

Understanding how this works can be quite difficult as it is academic but it is essential to harness the anabolic power of cell volume. The cell volume increases during muscle congestion through the coordinated activity of two carrier proteins located in the cell membrane.In the first step, the sodium-potassium (Na + / K +) congestion muscle moves three sodium ions out of the cell, to change the flow of two potassium ions. Because the sodium concentration is typically 10 to 20 times out of cells compared to the interior. Energy is required as ATP to pump sodium out of the cell against their concentration gradient.

In the second step, another pumping associated (co-transporter sodium-potassium-chloride) membrane called simultaneously transporting a sodium ion, potassium and one two chloride ions outside the cell inward same.

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