What Is Connective Tissue?

Why is connective tissue important to yoga?

A student wrote in and asked a good question:
She asked, “Connective tissue is composed of collagen and elastin. Bones are also connective tissue. Bones however exist of calcium and phosphorus. If I understood rightly this is all true. Then what are bones made of? Collagen or calcium and phosphorus?”

The concept of connective tissue is an important one for understanding movement in the body, and it can be a bit confusing. In this article, we’ll unpack the idea of connective tissue. We’ll hopefully add some clarity to your understanding of the concept of connective tissue. And, we’ll help you understand why connective tissue is so important to the practice of yoga asana.

To understand connective tissue specifically, let’s put it in context. I’m going to start with the big picture and then we’ll get more specific.

How are body structures organized?

Within our body we have systems that are organized around a function. For example, we have a circulatory system, a digestive system, and a skeletal system, as well as other systems. Each larger system is composed of organs that work together to support the function of that system. For example, in the circulatory system, one organ that we’re all probably familiar with is the heart. In the digestive system we have the stomach, large intestine, etc. Each organ, like the heart or the stomach, is composed of tissues.

What is a tissue?

A tissue is simply a group of similar cells that together perform a common function. There are four types of tissue in the body:

• Epithelial tissue
• Muscle tissue
• Nervous tissue
• Connective tissue

What is connective tissue?

Each specific type of tissue is defined by the components that make it up. Connective tissue is composed of:

• Protein fibers
• A ground substance in which the protein fibers are found
• Cells

There are many types of connective tissue. In fact, connective tissue is the most abundant type of tissue in the body and the most varied. When different types of protein fibers (collagen and elastin, for example, are both types of proteins), ground substance, and cells, are combined, we get different types of connective tissue. Some types of connective tissue include:

• Cartilage
• Bone
• Blood
• Other types
• And, what you’re probably thinking of as connective tissue, which is also called fascia

This is where it can get confusing. The broader category of tissue type and one specific example of that tissue type are both called connective tissue. (Human anatomists were maybe not the most creative folks when it came to naming things in the body!) To distinguish the specific example “connective tissue” from the broader category of a type of tissue, it’s more complete name is “connective tissue proper”. But, connective tissue proper isn’t a term that you’ve probably heard of as it’s not commonly used outside of anatomy circles. So, we’ll refer to the specific type of tissue that you’re probably thinking of as connective tissue, by its more common name of fascia.

What are bones and fascia made of?

So, to unpack the question posed by the student at the top of this article, bones are a type of connective tissue. Remember we said that all connective tissues are composed of protein fibers, ground substance, and cells. In the case of bones, the calcium and phosphorus present in bones are the “ground substance” which the protein fibers and cells are “swimming” in, so to speak. Protein fibers, such as collagen and elastin, are arranged within the ground substance of calcium, phosphorus, and other minerals. In bones, the protein fibers present are primarily collagen, as bones need more structure and less stretchiness (provided by elastin) than some other connective tissues, like fascia for example. So, the short answer is all of the above. Collagen fibers, as well as minerals like calcium and phosphorus, and some specific types of cells, all come together to make up our bones.

Why is connective tissue important to yoga?

The many types of connective tissue come together to create the body we move around with. We wouldn’t really have a body without the existence of these tissues. Our bones create a structure on which we attach other types of connective tissue, like muscles, tendons, and ligaments. Our fascia is the web-like connective tissue that connects all of the other structures and tissues in our body, together.

Additionally, that special type of connective tissue, fascia, wraps every muscle at every level, all the way down to the cellular level. So, when we are “stretching” something in yoga, we don’t just impact muscle fibers, we also impact fascia. Fascia literally connects everything to everything. If you looked at a human dissection, you’d see sheets of fascia running from our head to our toes. What that means is that when we are working with the body in any kind of movement practice, including yoga, it makes sense to me to think holistically.

For example, even if we think we have the intention to stretch just our quadriceps muscles, the fascia that wraps those muscles at every level is continuous with fascia above and below. So, when we have the intention to stretch our quadriceps, we are also impacting structures above and below. That happens whether we’re aware of it or not. And, tension in our body above, below, in front of, or behind a muscle or other structure, affects how that muscle or structure moves or is held in space. Again, that’s true whether we’re aware of it or not.

Interrelationship through fascia

Understanding this concept of the interrelationship through fascial connections is sometimes the answer to the question of why an area that you’ve been working to lengthen or increase mobility at, doesn’t seem to be changing. Sometimes the tension or restriction is actually somewhere else in the long line of fascial connection.

Understanding where these fascial connections occur throughout the body is a whole area of study in itself. That’s more than I’ll dive into in this article. But, the overall idea of interconnection of tissue in the body is worth exploring in your yoga practice, especially around those places where you feel stuck. Consider inquiring into what’s happening above and below the area(s) in your body where you feel like something is stuck. If you put some attention onto those surrounding areas, what do you notice? Sometimes those are the missing pieces of the asana puzzle.