Yes, Physical Inactivity is THAT Bad for You.

Dr. Kevin Ritzenthaler, DC, DCBCN

You’ve seen the headlines and heard the news stories declaring that a sedentary lifestyle is bad for your health. How bad?  Some compare its effects to being as dangerous as smoking a pack of cigarettes a day.

“Sitting is the new smoking” is a phrase that’s been credited to Dr. James Levine, director of the Mayo Clinic-Arizona State University Obesity Solutions Initiative.

Wow – sitting around is THAT bad for you?

Yes, it sure can be.  Lack of physical activity can increase your risk for diabetes, heart disease, osteoarthritis, cancer, gastrointestinal issues…pick most any disease and you can likely find some way to trace a risk factor back to lack of exercise. According to the National Institutes of Health, physical inactivity is a primary cause of most chronic diseases.1 Linking lack of exercise to disease is sort of like playing Six Degrees of Kevin Bacon – when you dig deep enough, you’ll see that it’s all connected.

But, it’s also important to understand that we’re not only talking about the stereotypical couch potato, eating cheese balls and playing video games all day. Many people work in professions whereby they spend the majority of the day in a car and at a desk . These people are just as vulnerable to the dangers of a sedentary lifestyle as those glued to their X-Box for 10 hours a day.

So, why does exercise play such an important role in our health?  Some of the connections are relatively straightforward, while others require us to dig a bit deeper.

Chronic Pain and Osteoarthritis

If you’ve learned anything from reading my articles it’s that your body was made to move. Without movement your muscles become weak from a lack of freshly oxygenated blood flow. A build-up of lactic acid can lead to muscle spasms and trigger points.  Joints that do not move do not produce the synovial fluid necessary to lubricate the joint and protective cartilage, eventually leading to breakdown, calcification, pain, and osteoarthritis. These are basic body mechanics that are pretty easy to understand once they are explained.

Heart Disease

Another fairly obvious example is heart disease. When you exercise, your heart rate rises, your blood pumps harder, and your lungs work harder. You can actually feel some of the effects the exercise is having on your body.  Depending on how out of shape you are, this “feeling” might be good or bad, but either way, you can feel the effects of exercise.  Likewise, you can also feel and see the effects on non-exercise: getting winded easily, the inability to “keep up” with others, weight gain, and flabby muscles, among others.


But some other links between exercise and disease are not as obvious.  For example, exercise can reduce your risk for cancer. According to the National Cancer Institute, people who exercise on a regular basis can lower their risk for colon cancer by 40 to 50 percent.2 Women who exercise at a moderate to vigorous level from more than three hours per week can lower their risk for breast cancer by 30-40%. This is true regardless of their family history of breast cancer.2 Exercise is known to help reduce the risk of other cancers as well.

But how does exercise reduce your risk of cancer? What’s the connection?

There are many ways in which exercise can reduce your risk for cancer and other chronic diseases. But to understand it, you need to look deeper. You need to understand the workings of the human body at a deeper level, a level that’s not so apparent to the average person.

Systems Approach

As a Functional Medicine practitioner, I have studied the biochemical processes of the body in depth. It is through this understanding of the systems of the body that you can understand the impact that a lack of exercise has on chronic disease.

Here are just a few examples of the benefits of exercise from a “systems” approach.


Your liver is the primary detoxifier for your body.  It acts as a filter for your blood and regulates chemical levels in the blood.  It transforms food into energy and nutrients for the body and controls the flow of those nutrients throughout the body. It also metabolizes drugs so that the body can get rid of them.

In order for the liver to do its many jobs, it requires an important enzyme called glutathione (GSH).  GSH has been called the “mother of all antioxidants” because of its importance in protecting your body. While exercise may temporarily deplete your supply of GSH, exercise is also your body’s signal to produce more of this protective enzyme.

In addition, excess weight can damage the liver and hamper its ability to function. Fatty liver disease is becoming a growing epidemic, estimated to affect 30-45% of Americans.3 The prevalence of fatty liver disease is being tied to the rising number of obese Americans.

DNA and Mitochondrial Function

On a microscopic level, exercise affects your DNA and your mitochondrial function. Humans are made up of 80% water. It is the liquid that the cells of our body are bathed in – it’s their environment, if you will. Inside that liquid are many molecules including vitamins and minerals. This environment is continually changing, based on the foods we eat, the environment we’re living in, and the amount of activity we do. The more physical activity you have, the better the environment for your cells, the better the environment, the lower the risk to damage to your DNA.  And what’s cancer? Cancer is damaged DNA.

New research is also showing that exercise can change the way our genes are shaped and how they function. One study showed that genes that play a role in energy metabolism, insulin response, and inflammation within muscles were positively impacted by exercise.4

There are a few popular sayings in the Functional Medicine community that drive home this point: “Genes alone do not define us, it’s what we bathe them in that makes us who we are,” or

“Every choice your make about food and exercise is either fighting disease or feeding it”.

Immune System Function

Exercise makes your immune system stronger. But think beyond building immunity to the common cold and consider the importance of your immune system when it comes to fighting chronic illness.

The white blood cells in your immune system protect you against bacteria, viruses, toxins, cancer cells and other harmful substances. When you exercise, a biochemical change occurs in your body that makes your immune cells better, stronger, and more potent in fending off disease. Additionally, exercise improves circulation of these immune cells in your blood.

Exercise. Just Do It.

I could list a plethora of other biochemical processes in the body that are negatively impacted by a lack of exercise, but I think that I’ve made my point.

Here are a few other points for you to absorb.  As of 2012, about half of all adults—117 million people—had one or more chronic health conditions. One of four adults had two or more chronic health conditions.5

Seven of the top 10 causes of death in 2010 were chronic diseases. Two of these chronic diseases—heart disease and cancer—together accounted for nearly 48% of all deaths.5

The human body was made to move, and this lack of movement in our modern society is having a direct, and extraodiarily detrimental impact on our health. But the good news is that you can do something about it.  Exercise can be free. You don’t need to join an expensive gym.  Talk to your health care provider about ways that you can begin an exercise regimen that is safe for you.