By Dr. Linda J. Dobberstein, DC, Board Certified in Clinical Nutrition
Physical activity. Movement. Exercise. From kicking your mom in the ribs during pregnancy throughout your lifespan, you have been made to move. Movement and being physically active is deeply intertwined with longevity and your health span. Yet, a sedentary lifestyle has become the way of life in the modernized world.
With that inactivity comes a host of problems that impact you in ways that you may not have realized or considered. The “use it or lose it” principle stands as a true defense against this health hazard. Here are some critical findings to help motivate and empower you to keep moving.
Physical Activity Slipping Away
You know that you need to be physically active, but it gets harder each year. Whether it is schedules and demands, nagging aches and pains, fatigue, or just simply being out of habit, it can be hard to maintain a regular exercise routine.
Furthermore, modern conveniences have downsized our number of steps and overall physical activities. Movement has been replaced by remote controls to voice activation and AI, and numerous other automated or mechanized things. Modern society is also now filled with gyms, personal trainers, fitness equipment and experts to motivate and teach you how to use your body.
Historical records show that the total number of steps taken in a day has declined by 50-70% since the introduction of powered machinery. The average step count in the US (1966-2007) was 7473. In 2010, the step count was 5340 (men) and 4912 (women). The Amish (2002) step count average is 18425 (men) and 14196 (women). A sedentary lifestyle is defined as less than 5000 steps per day. Society has indeed changed in the last 100 years!
Effects of Physical Inactivity
The effects of physical inactivity and sedentary lifestyles are among some of the most damaging things to your body. Physical inactivity creates a pro-inflammatory state in your body. You become more inflamed with inactivity. Furthermore, as the inactivity continues for months and years, numerous metabolic breakdowns, the development of obesity, and other vast changes in health occur.
Physical inactivity is associated with at least 35 chronic health conditions in 2012 research. These included accelerated biological aging/premature death, low cardiorespiratory fitness (VO2max), sarcopenia (age-related muscle loss), metabolic syndrome, obesity, insulin resistance, prediabetes, type 2 diabetes, nonalcoholic fatty liver disease/NAFLD, coronary heart disease, peripheral artery disease, hypertension, stroke, congestive heart failure, endothelial dysfunction, arterial dyslipidemia, hemostasis, deep vein thrombosis, cognitive dysfunction, depression and anxiety, osteoporosis, osteoarthritis, balance, bone fracture/falls, rheumatoid arthritis, colon cancer, breast cancer, endometrial cancer, gestational diabetes, pre-eclampsia, polycystic ovary syndrome, erectile dysfunction, pain, diverticulitis, constipation, and gallbladder diseases.
One of the major recommendations for treatment and prevention of these issues is to engage in daily moderate physical activity.
Cancer Risks and Physical Inactivity
The stark negative effects of physical inactivity have been linked to the development of many types of cancers since that previous study was published. We often think of toxins, genetics, or bad luck that results in the development of cancer. Research shows that an estimated 30-40% of cancers can be prevented by changing lifestyle and environmental risk factors, like engaging in regular physical activity.
The association between physical inactivity and cancer has a strong or moderate link with bladder, breast, colon, endometrial, esophageal, stomach, kidney, lung, ovarian, pancreas, and prostate. Obesity is a risk factor for endometrial, postmenopausal breast, colorectal, esophageal, kidney, meningioma, pancreatic, stomach, liver, multiple myeloma, ovarian, gallbladder and thyroid.
A sedentary lifestyle causes adverse changes with sex hormone binding globulin (SHBG), leading to increased estrogen and androgens in circulation. Additionally, metabolic hormones change, leading to decreased insulin sensitivity and increased blood glucose levels. This causes increased chronic low-grade inflammation and higher levels of leptin, TNF-a, C-Reactive Protein, IL-6, and more—a metabolic environment at risk for cancer.
These effects further increase oxidative stress and change methylation functions that affect DNA. Telomere length is shortened. Pro-inflammatory immune function and gut microbiome changes occur which increase the likelihood of cancer from sedentary lifestyles.
Effects of Inactivity on Your Blood
The health of your blood cells and blood flow is severely impacted by physical inactivity. It results in high blood levels of fibrinogen, elevated hematocrit, increased blood viscosity, increased platelet aggregability, diminished fibrinolysis, and low plasma volume.
Astonishingly, in as little as 3 days of physical inactivity glucose intolerance develops causing sugar to build up in your bloodstream and tissues. This constellation of changes increases your risk of heart attack and stroke regardless of your diet and other lifestyle factors.
Brain: Mental Health, Cognitive Function
Mental health and cognitive function are impacted by physical inactivity regardless of age. An extensive prospective cohort study in the UK evaluated leisure activity, screen time, sleep, and dementia risk of more than 431,000 adult participants, which were followed for an average of 9 years. The lowest risk of dementia was associated in individuals who had moderate-to high leisure physical activity, low to moderate sedentary behavior, and slept on average 7 hours per night. Those with greater sedentary activities were 22% more likely to develop dementia.
Further analysis of this data has been published in several studies. The JAMA September 2023 study clearly showed that among older adults, the more time spent in sedentary behaviors was significantly associated with higher incidence of all-cause dementia.
Other studies showed that participants with the most amount of TV viewing time experienced low hippocampal volume, i.e. that part of the brain shrunk. The results led to increased concerns of dementia, depression, and Parkinson’s disease.
The hippocampus is a brain structure that is essential for learning and memory. It converts short-term memories into long-term memories and connects them to emotions.
Kids Mental and Cognitive Health
Studies with adolescents show that depression, stress, and negative mood worsened with physical inactivity. A positive self-image, psychological well-being, and satisfaction with life and happiness were more prevalent in those who exercised and were more active.
A JAMA Pediatrics June 2024 publication demonstrated clear beneficial effects of physical activity in boys and girls 10-11 years old. Participants were followed for an average of 6 years. Numerous factors were evaluated for mental and physical health with participants engaging in running, sit-ups, standing broad jump, and sit and reach tests. Substantial improvements were noted in those who increased their physical activity including greater physical strength, cardiorespiratory health, endurance as well as reduced risk of anxiety, depression, and ADHD.
Kids, adolescents, and young adults are in a mental and emotional health crisis more than ever before. We must get them engaged in exercise and being physically active with other health supporting choices.
Autoimmune Disorders
Autoimmune disorders are on the rise just like so many other issues with poor health. Experts in the field of autoimmune disease highly recommend physical activity to manage autoimmune disorders as described in the review article “Physical activity and autoimmune diseases: Get moving and manage the disease”.
Research showed that disease severity was reduced with physical activity as it supports the release of anti-inflammatory cytokines, modulates the immune system to a healthier Th1/Th2 balance, and inhibits the release of pro-inflammatory cytokines. Patients who exercised also experienced reduced fatigue, better mood, cognitive function, better quality of life and cardiovascular profiles, reduced pain and risk of neuropathy, and healthier joint function.
Joints and Inactivity
The common belief is that osteoarthritis happens because of excessive physical activity and wear and tear. This can be true, but it also works the other way. Physical inactivity can also worsen osteoarthritis. Sitting more than 4 hours per day was found to cause worsening of knee arthritis as demonstrated by x-ray.
Engaging in physical activity with knee, hip, or other types of arthritis however helps reduce pain and improve physical function and quality of life comparable to the use of pain medications. Other benefits include reduced risk of falling, increased ability to live independently and participate in occupational and recreational activities, healthier body weight, and better sleep.
Mitochondria and Inactivity
Exercise is required for the function, remodeling, and birth of new mitochondria. These organelles are at the heart of energy production, health, and longevity. Every cell in your body has these energy factories and they follow the “use it or lose it” principle.
Physical inactivity from sedentary lifestyles leads to changes in mitochondria physiology, increases in free radical stress, and changes in how calcium is managed cellularly. The result is muscle fiber atrophy making you feel weaker, fatigued, more prone to injury, and aging faster.
However, exercise can offset these changes and improve mitochondrial function. The adverse effect of a sedentary lifestyle is even more than this snapshot. History shows us that physical inactivity was something to contend with even thousands of years ago.
What Does History Tell Us?
In the fifth century BC, Hippocrates wrote, “All parts of the body, if used in moderation and exercised in labors to which each is accustomed, become thereby healthy and well developed and age slowly; but if they are unused and left idle, they become liable to disease, defective in growth and age quickly.”
Jeremiah Morris was the professor who invented the field of physical activity epidemiology in the 1950’s. In his 10th decade of life, he wrote “We in the West are the first generation in human history in which the mass of the population has to deliberately exercise to be healthy. How can society’s collective adaptations match?”
Now What?
It’s likely that you have watched individuals or even find yourself succumbing to the effects of physical inactivity. If you have a sedentary lifestyle, and are unsure of where to start, walk a few more minutes extra each day and gradually increase the amount and intensity. Do not attempt to start exercising at the level that you performed at last year or 20 years ago. Your metabolic chemistry is not the same as what you expect it to be. Your muscles may have atrophied making you more susceptible to injury. Consider a beginner class at the YMCA or community center.
If you are recovering from an illness, disabled, or homebound, start with isometric exercises. Examples of this include squeezing a ball with your hand, making a fist and squeezing it, clenching your buttocks together, squeezing your thigh muscles and then the whole leg. Start with 5 repetitions 1-2 times per day and then gradually work your way up to 10 reps, then 20, then 30 reps 1-2 times/day. Add a one-pound weight or more as you get stronger. Work with your health care team for proper support and training.
If you are a pro at exercise or are regularly engaged in moderate to high amounts of physical activity, keep up the great work! Feed your body well with your diet and longevity nutrients to keep up with the demands and encourage those along the journey.
I don’t know about you, but any one of these findings is an incentive for me to be as physically active as life’s limitations allow. It’s not too late to change! How are you doing with your steps, strength, and aerobic activities?
