When you go to the doctor and are told that it is a normal part of aging to become tired and experience pain, most people are satisfied with that answer. It sounds reasonable that fatigue and pain are caused by aging, which is why the doctor’s offer of stimulants and pain-relieving medications is received with gratitude.
But age has no causality (cause-and-effect relationship) with fatigue and pain in the body. This means that the relationship between age and fatigue/pain is merely statistical. What causes fatigue and pain in the body is that cells suffer from a lack of oxygen. Then you become tired, and the lack of oxygen in one or more cells means that their energy production is impaired. Those cells then try to produce energy without oxygen, i.e., the cells begin to ferment glucose, which, however, is nowhere near enough to compensate for the lack of oxygen, and you have less energy, i.e., you become tired. The fermentation of glucose produces a by-product, lactic acid, which is acidic. In the alkaline environment inside the cell, you perceive the lactic acid as pain. Fortunately, lactic acid immediately loses a hydrogen (H) and is converted into lactate, which is alkaline, and the pain disappears. But as long as the fermentation of glucose continues, you feel pain.
Why does the supply of oxygen to the cells decrease?
Oxygen is transported through the arteries by red blood cells, which are propelled by the heart’s pulsations and the healthy, elastic, and resilient muscular layer of the arteries. When the red blood cells reach the outermost and narrowest arteries, known as terminal arterioles, they must be able to pass through this short but constricted passage. However, a red blood cell may have a larger outer diameter than the inner diameter of a terminal arteriole. If the muscular layer of the terminal arteriole has lost its elasticity and resilience, it becomes more difficult for the heart, and it takes longer for red blood cells to pass through the terminal arterioles and enter the downstream capillaries.
As a result, fewer oxygen-filled red blood cells are available in the capillaries, from which oxygen must pass through the surrounding tissue to reach and enter individual cells. Fewer red blood cells mean less oxygen available to the cells.
Why does the muscular layer of the terminal arterioles become stiff?
It has been 25 years since Furchgott, Ignarro, and Murad were awarded the Nobel Prize in Physiology or Medicine for their discovery that the muscular layer of blood vessels (tunica media) loses its elasticity and resilience as the delivery of nitric oxide (NO) from the endothelial cells (the inner lining of the vessels) decreases. Unfortunately, this knowledge has not been reflected in more recent research in the field of cardiovascular medicine.
All cells, including the endothelial cells of the arteries, have a hairy outer surface (the glycocalyx). As the glycocalyx is damaged—for example by bacteria, viruses, sugar, and insulin—and consequently becomes thinner, the endothelial cells deliver less NO to the muscular layer of the vessel wall (tunica media), which then becomes ”stiff.” As a result, it becomes increasingly difficult for the heart to pump enough red blood cells to prevent your body’s cells from suffering from oxygen deficiency. This can affect all parts of the body, from the arteries in the large skeletal muscles and the heart muscle to those of the eyes, ears, and brain, reducing their ability to deliver sufficient life-giving oxygen.
The book How Is Your Glycocalyx? The Healthier It Is, the Healthier You Are describes how my studies over more than seven years (primarily on PubMed, where all medical scientific articles published in recognized scientific journals are available) led me to the realization of the importance of the glycocalyx for our health.
Lasse Blomdahl, Why do we become tired and develop pain as we age?
