| Fitness flexibility stretching

Stretching: The importance and benefits of flexibility

By Robert Walker

This is an excerpt from the UMZUfit Mobility Course. For more information and an even more in depth look into mobility and fitness as a whole, make sure to check out UMZUfit!

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Table Of Contents


the big three of fitness

Let’s consider fitness endeavours as a whole. Look around your gym. What areas of fitness are people most likely to be working on? 

You will see that your gym is most likely divided into 2 parts - one for cardiovascular fitness - the treadmills, ellipticals, rowing machines - and another that is dedicated to muscular strength - the benches, dumbbells and isolation machines. Yet, in fitness, there is a “Big Three” - and that Big Three is made up of cardiovascular fitness, muscular strength, and flexibility training. 

Historically, the latter of the three is the least popular, and this is very evident in most gyms. With the boom in Internet usage has come a boom in access to information regarding fitness. 

Studies are everywhere now touting the relationship between cardiovascular fitness, longevity of life, and energy output. Likewise, studies are abound of the benefits of strength training to performance and attraction. 

Simply stated, the benefits of the first two areas of The Big Three are… sexier than the perceived benefits of flexibility training. 

Flexibility training is something we all know is good, but because many are uninformed on the true benefits of flexibility training, this form of exercise comes off as tedious. In more recent years even, research has come out calling “stretching” dangerous - saying that stretching regularly is a leading cause of injury in runners. This generalization is misleading, as it is truly only referring to a form of stretching known as ballistic stretching, which we will cover later on in this course. But writings like this have given stretching and mobility training a bad name. 

The truth is, the Big Three of fitness are not separate. Each one influences and accentuates the other. Flexibility training enhances your cardiovascular fitness and your strength and power output. I am glad that you are reading this, because this course will be the missing ingredient to your fitness endeavours. 

By really understanding the body and the importance of flexibility training, you will be able to construct an exercise routine that will keep you healthy into your sixties and seventies. To get you excited about taking on this course, I am going to quickly run through the rewards you will reap from including daily stretching into your routine. 

These include reduced stiffness, reduced risk of injury, improved body posture, and symmetry, enhanced relaxation, lower stress and tension, pain relief, enhanced physical fitness, ease of daily life. If you participate in sports, you will enhance athletic performance, improve efficiency of your movements, reduce severity of injury, decrease delayed onset muscle soreness, and reduce the duration of recovery. 

To sum this all up, there are 3 major areas of training - cardiovascular, strength and flexibility. While the latter is often neglected as too tedious, each one of these three must be weighed as equally important. By making this jump, you will enhance your performance holistically. Each one plays a role in improving the other. 

Next up, we will dive into the Big Three holistic networks in your body that you need to address to achieve optimal performance.

Learn More: What Is Fat And How Do You Get Rid Of It | UMZU


the big three networks

In this section, we are going to make an attempt to define what makes a human. The overall goal of this endeavor is to leave this section with a picture of what is truly the most important to consider when it comes to human health. 

To do this, we must look first at what we would call “holistic networks” in the body - what systems are truly so interweaving, broad, and impactful that they make a human what it is?

Let us begin with a Thought Experiment beautifully brought forward by Thomas Meyers in his book “Anatomy Trains.” In his book, he asks the question… Which physiological systems of the body, if we could magically extract them intact, would show us the precise shape of the body, inside and out? In other words, which systems of the body are truly holistic? 

The natural first thought is the skeletal system - the bones. Look around your home, office, or out on the street and imagine everyone you see as solely skeletons. You can see what these skeletons are doing and you may even be able to get a basic idea of how these skeletons are feeling by their body posture, but there is certainly something missing. 

Are these people fat or thin? Muscular or inactive? There is simply too much missing information to define the skeletal figure as a holistic system. 

Next, let’s look at the digestive system. If you extract everything else from the body, you would only see a floating set of organs. While you may be able to extract some additional information from the gut, it gives an even inferior image of the human body compared to the skeletal system. Not a holistic candidate. 

Now, let’s address the skin. We are getting a little closer here. We can now see the exact shape of the body - we can recognize emotions and facial expressions, but we would know nothing about the inner workings of the body; therefore we cannot call the skin a holistic system. So are there truly any holistic networks in the body?

Meyers defines three - the nervous system, the circulatory system and the fibrous system. This idea of these three holistic networks was first brought forward by Vesalius in 1548, when he rendered an image for the three networks, showing them interweaving throughout the body, creating the most accurate shape of what the body truly is. Let’s take a dive into all three.


the nervous system

If we were to extract only the nervous system, we would learn a great deal about the human body. We would have the brain, the spinal cord, and the vertebrae. We would see the shape of each organ, the complete digestive system, and the heart. The hands, feet, and back would be particularly visible, as they are jam packed with nerve endings. 

If your nervous system is healthy and functioning properly, there is no part of your body that would not feel. The only things missing from the image of the complete and healthy nervous system would be your tissues, bones, and the actual tubes that bring blood, food, and air throughout your body.


the circulatory system

If we extracted everything from the body besides the vascular system, we would also be able to see the full representation of the human body. We would again see the heart and the brain, the arteries, veins and lungs.

 In fact, we would see about 100,000 km of capillaries. 

We would see the complete lymphatic and cerebrospinal fluid systems. We would even see cells, which depend so much on the fluid system to operate.


the fibrous system

The final holistic network is the fibrous or fascial system. If one were to remove all other systems besides the fibrillar elements and the connective tissue, one would be able to see the entire body. 

The fibrous system is made up of almost entirely collagen, with additional elastin and reticulin. 

This final system would show the bones, cartilage, tendons, and ligaments in fiber form. As Meyers puts it, “the fascial web so permeates the body as to part of the immediate environment of every cell. Without its support, the brain would be runny custard, the liver would spread through the abdominal cavity and we would end up with a puddle at our own feet.”


comparing networks

Now that we have defined the three holistic networks of the body, let’s compare the three. 

First, all three are “networks” with a large amount of complexity, running throughout the entire body, touching nearly every inch of you. It is worth noting that all three interweave both anatomically and functionally. 

Second, all three are made of tubes - a fundamental shape in biology. Every early multicellular organism was a tube, and that shape has not changed as we have evolved over millions of years. The neuron is a tube. The capillary is a tube and the collagen fibril creates a helixed tube. 

Next, all three networks convey information. The neural network carries encoded information that helps the body make decisions, the circulatory network carries chemical information, exchanging actual physical substances throughout the body. The fascial system conveys mechanical information, helping the body move. All three of these systems intertwine and communicate with one another in order to create a human.

This section represents a radical simplification of the body; however, it is necessary to understand this one point - the three holistic networks - the nervous system, the circulatory system and the fascial system - should be the main focus of your health endeavours. These three networks make you who you are and none can be ignored, because they all work in tandem. In this course, we will be working on building the health of the fascial system through stretching, flexibility and mobility training.


benefits of stretching


Flexibility is all about Range of Motion or ROM. Essentially, flexibility is how far one can reach, bend, and turn. There are many things that go into this - the muscles, the fascia, the bones, the joints, the ligaments, the tendons, and the skin; however, for flexibility training, you only have control over muscles and the fascia.


Mobility, on the other hand, is all about joints and their ability to act in a full range of motion. To have good mobility, one must possess good flexibility, muscular strength, and stability. It is VERY important to note, that one should possess both mobility and flexibility and we will be working towards both in this course.


There are many forms of stretching that we will address in this course, but in a nutshell, stretching is the process of placing body parts in positions so that the muscles are extended, with the goal of lengthening muscles and their associated soft tissues. Stretching will impact the health of your muscles, fascia, tendons, skin, and scar tissue.

In this course, we will be working with both static and dynamic stretching, which will work in tandem to improve both your flexibility and your mobility at once.


flexibility issues

As we discussed earlier, flexibility training is one portion of the complete picture of fitness. It is essential to create a balanced fitness regimen that addresses the Big Three of fitness to complete the wheel. 

Also within the area of flexibility training, it is important to note that one person can be flexible and mobile in only one area, just like someone can have a strong chest and weak legs. In this light, we will be working on a balanced flexibility and mobility routine throughout the entire body.

Read More: The Many Benefits of Resistance Training


At its most basic level, poor flexibility and mobility, which we will call FAM from now on, limits one’s range of motion. This can be a major factor in muscle and joint pain. It can also impede your ability to do things like bend over or look behind your back.

In regards to performance, poor FAM can lead to improper muscle action. If your muscles cannot contract and relax the way they should, decreased performance and poor muscular control can result. If your muscles are short and tight, you will also experience a loss of strength and power.

Poor FAM can also lead to poor blood flow, which is vital to address. The circulatory system is one of our three holistic networks, and is therefore paramount in our health endeavours. Circulation ensures that adequate amounts of oxygen and nutrients are delivered to your muscles. Poor circulation can cause muscle fatigue and inhibit one’s ability to recover from exercise, and therefore will impede muscle growth.

Finally, and likely the most obvious, poor FAM can lead to injury and discomfort.


Flexibility and mobility can be restricted by many things - some of which are out of our control. Bones, ligaments, muscle size, tendons, and skin can all affect range of motion.

Gender, age, temperature, and clothing can also affect ROM. Most of these issues have to do with the amount of collagen in your system, so it is highly recommended that you are either supplementing with collagen or eating collagen-heavy foods (which are hard to find) while you are working through this course.


benefits of stretching


Here we see Mobility and Flexibility meet. By placing body parts in certain positions through stretching, we are able to extend the length of muscles and the associated fascia. When muscles are lengthened, there is a consequent reduction in muscular tension. From here, it is easy to see how range of motion can be increased.

By increasing range of motion, we can further extend our limbs without the risk of damage. Why would you want this? Greater range of motion leads to increased comfort, a greater ability to move more freely and a reduced risk of injury.


Unfortunately, the extent of research around flexibility as a mode of injury prevention is limited. There actually is no real evidence that stretching alone can reduce rate of injury; however, there is evidence that athletes with a restricted range of motion are more likely to be injured than a control. 

One study by Witvrouw on soccer players with limited flexibility in their quadriceps and hamstrings showed that the limited flexibility group was more likely to be injured during soccer season. Keep in mind that this is a long earned factor of the flexible soccer players. Studies show that stretching right before play has no effect on reducing injury rate - only the factor of being a flexible person has that power. 

I will repeat this frequently throughout this course - flexibility and mobility training are long-term journeys. Do not expect a quick fix and quick results.


Injuries can be divided into two categories - chronic and acute. 

Acute injuries are those that have occured recently, while chronic injuries remain symptomatic beyond their expected latency of healing. Both types of injury involve damaged tissue, usually to the bone, muscle, ligament, tendon, nerve, or muscle tissue and are often a combination of the above. Injuries result in the formation of inflammation and scar tissue. 

Stretching is essential to injury rehabilitation because it promotes the restoration of normal joint function and prevents the formation of excessive scar tissue.

Research also suggests that stretching has a restorative effect on the cellular level. There is evidence that the elongation of muscles through stretching increases the metabolic processes of cell proliferation, differentiation, and matrix formation, which suggests that stretching is beneficial for the healing of tendons and ligaments. 

One study by Bosch showed increases in collagen types I and III as a response to cyclic stretching. Another study by Squier suggests that stretching may increase myofibroblasts - the precursor to muscle cells. Yet another study by Skutek suggests that stretching activates intracellular signaling pathways that may affect tendon remodeling.

With all of this being said, stretching for injury must be treated with care and must be administered during the correct stage of the healing process in order to prevent additional inflammation from occurring. It is often the case that proper joint mobilization must be established first when recovering from injury before beginning to stretch. 

While this program does not recommend “aggressive stretching” in any capacity, aggressive stretching should never be practiced on painful tissue.


Contracted muscles affect the resting position of joints and therefore affect postural alignment. For example, a tight pectoralis muscle will force forward posture and tight hamstrings will result in a reduced lower back curve. Posture in its entirety is a result of muscle length and strength. While you will work on strength in other courses inside of UMZUfit, we will address the muscle lengthening component of posture in this course.


Does your job require that you spend a lot of time in front of a computer, sitting down, or completely sedentary? This is becoming more and more of a problem in this age of advanced technology. 

This area specifically affects me - as I spend my entire day in front of a computer trying to make UMZU the best company in the world. Sedentary work reduces the frequency and amplitude of motion you perform every day. 

Many people have neck pain, shoulder pain and back pain that pops up seemingly out of nowhere, and this pain is almost always attributed to a sedentary lifestyle. Studies have shown a strong correlation between computer use and lower back pain. If this sounds like your life, then stretching will be a critical component of you developing a healthy lifestyle.


Once you begin this course, you will notice that after the initial discomfort during stretching, it results in a relaxed feeling in the target group almost instantly. 

While the research on the actual mechanism of this relaxation is minimal, some research suggests that stretching may induce some level of anesthesia, ultimately leading to that good feeling you get post stretching.


A whomping 80% of Americans experience lower back pain at some point in their lives. This can be very disruptive to your life. 

A lack of flexibility is often the culprit. Shortened muscles affect the resting and functioning positions of the spine. Specifically, shortened hamstring length or poor hip flexion is typically the cause. 

In addition, your lower back pain may be the result of a right to left imbalance or vice versa. For example, a shortened psoas muscle, a key component of the Deep Front Line (see Dissecting the Lines for more), may cause a chronic lean to the right, even if it is virtually impossible to notice. 

These kinds of imbalances may also contribute to lower back pain. By eliminating imbalances and increasing the length of the Superficial Back Line down through the hamstrings, you may be able to address that lower back pain plaguing your life.


Several things happen as you age. If you are over the age of 40, then you may be experiencing challenges with cardiovascular health, balance, strength, and flexibility. This is likely due to a decline in collagen and a stiffening in connective tissues or fascia. Muscle atrophy is also a consideration, as ageing comes with a loss in size and number of muscle cells. 

These changes happen to everyone, but the rate at which you experience these changes can be altered through activity. Exercise programs around strength and flexibility can help to extend the onset of this degradation. Through this program, we will be improving the health of your fascia and muscles through stretching, which should help to extend your time not having to worry about stiffness and physical effects of aging.


There is an ongoing debate in the stretching realm that stretching too much causes a loss in muscle power and joint stability. If you follow the safe rules for stretching outlined in this course, then you will not have to worry about this. In fact, stretching can actually result in an increase in power, because as we lengthen the muscles, we are increasing the distance over which the muscles are able to contract.


Everyone who works out has experienced Delayed Onset Muscle Soreness. You may have heard of it referred to as DOMS - specifically around leg day. The DOMS occurs when your muscles are tighter, stiffer, and more sore the day after training them. This soreness is the result of micro tears, blood pooling, and the accumulation of lactic acid. 

Stretching to relieve DOMS is a hotly contested topic in the field, as a number of studies have shown that stretching post-workout does absolutely nothing. In fact, it may even increase the risk of DOMS if you are performing stretching exercises on areas to which you are not accustomed.

Relieving DOMS is all about improving circulation to reduce inflammation and blood pooling; therefore it makes sense that light non-strenuous activity on the target area would improve blood flow and also reduce DOMS.

Here is where I stand on the issue - while the effects on DOMS of stretching immediately post-workout are likely nil, being flexible in the target area will lengthen your muscle fibers, preventing blood pooling by increasing circulation of blood through the muscles and also resulting in the removal of lactic acid.

So just by doing this program and by becoming a more flexible person, you should experience less DOMS - and if you are experiencing DOMS, do not stay still! Go for a walk and get the blood pumping to the target area.


Fatigue is a problem for almost everyone, but did you know that stretching can actually help to reduce chronic fatigue? 

Here is why - you are always working a muscle.

Every muscle has an opposite and opposing muscle working to keep bodily balance. By extending the length of the opposing muscle, the working muscle has to work less and expend less energy to perform a task. Therefore, by improving the flexibility of opposing muscles, you expend less energy doing your everyday work and will be able to use that energy on something else!

To get the rest of this course and to get access to every UMZUfit course available make sure to check out the UMZUfit platform!

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