Fitness centers, gyms, basketball and tennis courts are all closed now. The threat of viral contamination is real. Individuals and families are focusing on optimizing their immune system in an effort to stay healthy and thrive. What is the immune system and its functions? What happens to our immune system as we age? Does exercise improve immune system function? Is it true that exercise improves your aging immune system? How does our immune system keep us healthy? Let’s dig in.
The Immune System and Its Functions
The main function of our immune system is to keep us healthy and in good repair. It has many functions and responsibilities. On a daily basis our cells and other tissues breakdown which our immune system constantly repairs. It also protects us from invaders such as bacteria, parasites, viruses, and other microbes (1). The immune system quickly identifies them and destroys them prior to them actually causing damage to our body and making us sick. It also scans for pre-cancer cells that are destroyed prior to advancing and causing illness. A variety of immune cells are used by the immune system to carry out these many functions. A couple of examples of these cells are T cells and B cells, which are formed by stem cells in our bone marrow and phagocytes, which kill foreign invaders by actually gobbling them up. There are many, many more types of immune cells.
Our immune system has a massive job, and keeping it healthy should be priority number one if we want the best chance at overall health as we age.
Immunity Declines as We Age
The immune system, like most of our body systems, loses a bit of oomph as we age. In fact, this immune system decline actually starts not in those golden years, but much earlier—typically in our 20s—and gradually declines throughout life. Understandably, as our system progressively weakens as we age, this naturally hinders its disease-fighting abilities. This is why we see more disease in those in their 60s and beyond than we might see in a twenty- or thirtysomething. One study, however, suggests that exercising regularly as you age may help maintain a strong and healthy immune system and prevent that otherwise inevitable decline (2).
Exercise May Improve Your Immune System and Slow Its Decline
A key term to understand is immunesenescence. It’s a big word, but in regards to this study, it simply means the decline in immune function associated with aging. The purpose of the study was to determine if the immune system could benefit from exercise during aging. Many immune function levels were analyzed, including T cells, cytokines, and others. There were three groups of participants.
- Long-distance cyclists (age 55–79) with a long history of exercise
- Healthy but inactive group (age 55-79)
- Healthy young adults.
The results? Compared to the older participants in the healthy, inactive group, the immune function of the similar aged active cyclists was significantly better. In fact, in certain immune levels, such as the production of T cells, the active cyclists’ levels were comparable to the young healthy, inactive group. Meaning, in some immune functions, exercising into your 50s, 60s, and 70s could slow decline so drastically that it matches that of someone half or more of your age. The research concluded that the decline in our immune system may in part be due to the reduced levels of exercise as we age. The takeaway message is clear: Rather than becomes less active as we age we need to keep exercising throughout life to keep our immune systems in top performance.
Important Things to Know About Immunity
The immune system functions in an endless array of ways to keep us healthy and prevent diseases. Let’s take a look at a handful of fascinating studies highlighting the importance of our immune system:
- Platelets, found circulating in our blood, collaborate with our immune system, trapping invading bacteria and other microbes so phagocytes can quickly destroy and dispose of them (3)
- The immune system is so loyal to its own body that when donor stem cells, or allogeneic stem cells, are introduced into its host, studies have shown that the immune system will attack these “invading” stem cells (4).
- Activation of genes in phagocytes in the brain may hold promise in the treatment of dementia (5).
The immune system is critical is good health and vitality. Its responsibilities are vast and including constant cellular repair and fighting off invaders such as bacteria and viruses. The immune system function decreases with age. Exercise improves your aging immune system, as exercise has been demonstrated to slow this decline. During this COVID pandemic, everyone needs a top-performing immune system. Do yourself and your family a favor. While you are binging on Netflix start some bodyweight exercises. Dust off the exercise equipment in the basement. Those resistance bands in the closets can be effectively used to tone muscles. During these challenging times please be safe, isolated and confident that if we work together as a nation we can overcome this crisis.
1.Schultz KT, Grieder F. Structure and function of the immune system. Toxicol Pathol. 1987;15(3):262-4.
2. Duggal NA, Pollock RD, Lazarus NR, Harridge S, Lord JM. Major features of immunesenescence, including reduced thymic output, are ameliorated by high levels of physical activity in adulthood. Aging Cell. 2018;17(2)
4.Gaertner F, Ahmad Z, Rosenberger G, et al. Migrating Platelets Are Mechano-scavengers that Collect and Bundle Bacteria. Cell. 2017;171(6):1368-1382.e23.
5.Kleinberger G, Brendel M, Mracsko E, et al. The FTD-like syndrome causing TREM2 T66M mutation impairs microglia function, brain perfusion, and glucose metabolism. EMBO J. 2017;36(13):1837-53.