How Does Exercise Prolong Life? – Jesse Santiano M.D.

There is a dose-response relationship between physical activity and length of life. The more and vigorous the movement, the longer the life. That was the topic of Physical Activity Correlates with Life Span. The more powerful the movement, the longer the life.

So how does the body do that? How can movement and exercise make a person live long? The answer is in the following:

By Improving the Inner Lining (endothelium) of the blood vessels.

Blood supply to the whole body needs a well-functioning vascular system. The inner lining of the arteries should ensure a smooth flow without blockage.

Exercise allows the endothelial cells to form substances that make arteries accommodate the increased blood flow, preventing unnecessary blood clot formation, repair any defects in the inner lining of the arteries, stop premature cell death of the endothelial cells (apoptosis), and avoiding unwanted sticking of white blood cells to the arterial lining that can cause damage.

Endotelijalna_ćelija — Cross-section of an Artery

Exercise increases Nitric Oxide formation.

The more intense the activity is, the higher the need for blood. For every pulsation of blood after every heart contraction, the arterial wall distends and causes shear stress. The shear stress stimulates the endothelial cells to produce nitric oxide (NO). NO plays a significant role in maintaining the patency and functionality of the endothelium.

Exercise Increases Insulin Sensitivity in the Skeletal Muscles

Insulin Sensitivity is the skeletal muscle’s ability to respond to the circulating hormone insulin to accept blood glucose to enter the skeletal muscles. The skeletal muscles require glucose to form glycogen. Glycogen is the fuel supply of the skeletal muscles needed to provide energy for the skeletal muscle to move. The higher the activity level, the more glycogen is used that creates a demand for more glucose. This facilitates the insulin to “push” the glucose into the skeletal muscles. The lower the blood sugar.

Exercise Prevents Fatty Liver that initiates of Metabolic Syndrome.

If blood glucose is not excessive, then fatty liver formation is prevented. Fatty liver leads to liver dysfunction. It increases the formation of Very-Low Density Lipoproteins (VLDL) and Triglycerides that spread all over the body and cause problems in the blood vessel lining.

Stage_of_liver_damage — Stage of Fatty Liver

Exercise Leads to Blood Sugar Control by Preventing Insulin Resistance and Hyperinsulinemia

If the skeletal muscles and the liver are not responding appropriately to insulin, then a state of insulin resistance develops. The pancreas will compensate by making more insulin to have help “push” the glucose into the skeletal muscle and liver cells. The pancreas has to protect the body from the effects of high blood sugar (hyperglycemia). Persistent hyperglycemia is toxic to the human body and leads to Type 2 diabetes.

But hyperinsulinemia carries a high price tag. There are insulin receptors throughout the body, and they may not be insulin resistant. The excess insulin will then cause unwanted stimulation of the other organs, leading to different disease conditions. The most common is hypertension.

2052fig01 — **Figure 1.** Physiology of insulin signaling in metabolic syndrome. Overview of the physiology of insulin signaling in metabolic syndrome. Insulin actions that are insulin resistant in metabolic syndrome are labeled in red, whereas insulin actions that remain insulin sensitive in metabolic syndrome are marked in green. TG indicates triglycerides, FFA, free fatty acids. Original artwork by Leah A. Klein.

Exercise Prevents and Reduces Visceral Fat, therefore, Decreasing inflammation.

Visceral fat is the fat inside the abdominal cavity. Once fatty liver develops because of the persistently high blood sugar, the excess glucose increases the size of the visceral fat that infiltrates the other solid organs like the pancreas and starts to secrete pro-inflammatory substances and reactive oxygen species (ROS) that destroys the pancreas and spread to other organs to cause inflammation, and disease.

Abdominal_obesity_in_men — Beer, Soda, Pop, Too Many Sweets/Carbs Belly

Exercise Increases Myokine Release

Myokines are signaling proteins secreted by skeletal muscles in a dose-response manner. Myokines exert beneficial effects on the whole body like exercise adaptation, tissue regeneration and repair, anti-obesity, immune regulation, cancer prevention, heat generation, tissue, and blood vessel repair.

Exercise Increases High-Density Lipoprotein (HDL)

HDL, commonly known as the “good cholesterol,” has many protective functions. The lower the HDL, the higher the risk of developing a heart attack. So far, HDL increasing drugs have not duplicated the protective effects of improved HDL functionality and number associated with exercise.

HDL “cleans up” the atherosclerotic deposits in the blood vessels (reverse cholesterol transport) thru cholesterol efflux. Cholesterol efflux is the mechanism wherein the HDL carries the lipoproteins are removed from the atherosclerotic plaque back to the liver. HDL also contributes to a healthy functioning endothelium, has anti-inflammatory and anti-oxidative properties.

Red Ts means to prevent, Green arrow – Good effect, Black arrow – Bad effect, SMC smooth muscle cells, ox LDL – oxidized LDL

Exercise Addresses all the Criteria in Developing Metabolic Syndrome

According to the NCEP ATP III protocol, a person has metabolic syndrome if you have hypertriglyceridemia, obesity, high blood sugar, low HDL, and hypertension. Metabolic syndrome is associated with many disease conditions. Top Causes of Mortality, lungs, gout, and eye, coagulation, periodontal disease, erectile dysfunction, atrial fibrillation, cancer, ear problems, tinnitus, and vertigo, male genitourinary and female reproductive system, and heartburn.

Looking back at this article, you can see that exercise addresses all the factors contributing to metabolic syndrome, prevent many diseases, and maintains a healthy body. That is how exercise prolongs life.

If you get any value in this article, please subscribe and share it with others.

Thanks for reading.

Reference:

Green et al. Exercise and cardiovascular risk reduction: Time to update the rationale for exercise? . 2008 Aug; 105(2): 766–768.

Image Credits:

Endothelium by By DRosenbach at English Wikipedia, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=30308742
Nitric Oxide by By YinY. – Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=54660537
Beer Belly By Diabetes – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=65981665
Myokines: Christoph Hoffmann, and Cora Weigert Cold Spring Harbor Perspectives in Medicine 2017;7:a029793 Cold Spring Harbor Laboratory Press
Hyperinsulinemia by Leah Klein: https://www.ahajournals.org/doi/full/10.1161/ATVBAHA.111.241919?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%3dpubmed
HDL on the Blood Vessel by By Rfch – Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=4596470
Fatty Liver Image is Public Domain Stages of Fatty Liver: The original uploader was Countincr at English Wikipedia. (Original text: National Digestive Diseases Information Clearinghouse) – https://catalog.niddk.nih.gov/catalog/ImageLibrary/detail.cfm?id=154, Public Domain, https://commons.wikimedia.org/w/index.php?curid=2310132