As Covid-19 waxes and wanes, we might feel we’re aging faster than ever. The truth is – we are. Accelerated aging can result from many factors, including dealing with a global pandemic. Issues such as infectious disease exposure, chronic stress, and loneliness can speed up aging. But there is something that can be done to help slow down this process – exercise.
This article discusses the latest research on how aging is measured and how the pandemic may be speeding up the aging process. We also reveal how exercise can help ward off chronic inflammation, exposure to infection, and the stress that accelerates aging.
How is Aging Measured?
Researchers have been working hard to find the best approach to measure aging. According to Nature, one of the most promising approaches, epigenetics, emerged about a decade ago. Methyl groups turn genes on or off by affecting interactions between the DNA and other proteins. At specific sites in the genome, methyl groups accumulate in predictable patterns over time. In 2013, researchers developed algorithms to calculate a person’s epigenetic age based on these patterns. Scientists can now compare a person’s cellular age with their chronological age with a blood or tissue sample. “If their epigenetic age is older than their number of laps around the Sun would suggest, studies show a small but significant correlation with worse health, more pain, and a higher risk of premature death,” states Luigi Ferrucci to Nature, a geriatrician, and epidemiologist at the U.S. National Institute on Aging.
However, epigenetic age is not the only method scientists use to measure this process. Ronald DePinho, M.D., a cancer-biology researcher at the University of Texas MD Anderson Cancer Center, tells Nature that aging is also connected with certain degenerative states, including senescence (cellular death), tissue inflammation, and metabolic dysfunction. Extensive research by DePinho and colleagues, among many others, has linked these indications of aging to dysfunction in the telomeres at the ends of chromosomes. Telomeres shorten over time, and some researchers use their length to measure cellular age. The truth is the aging process involves a whole series of biological changes that drives their development. Scientists call these changes hallmarks, and around nine have been identified. All told, these measurement strategies are helping researchers in their quest to understand how humans age. But the pandemic has added a new challenge to this work. Scientists are now racing to understand how COVID-19 affects the aging process – both in the mind and body.
Is COVID Aging Us?
The short answer is yes. According to Nature, scientists find that behaviors and life events can also affect epigenetic age – including exposure to infection. Ferrucci thinks the SARS-CoV-2 virus that causes COVID-19 can also result in chronic inflammation and accelerated aging. In COVID-19, inflammation emerges through several pathways, including cellular senescence. This action often leads to a flood of immune responses, including the secretion of cytokines and other inflammatory molecules. When inflammatory reactions to the COVID-19 virus are high, the immune system can become less resilient in the long term, leaving some people less able to resist the effects of aging.
Moreover, even if someone never gets the virus, the outcomes from the pandemic are proving to be problematic – including the effects of chronic stress. Research suggests that stress can contribute to accelerated aging. A recent study found that cumulative stress was associated with accelerated epigenetic aging in healthy, young-to-middle-aged participants. Results found that the relationship between stress and age acceleration was most prominent in those with poor emotion regulation and was related to behavioral factors such as smoking and Body Mass Index (BMI).
According to Nature, another aging research study conducted by Erika Wolf of the Boston University School of Medicine and the National Center for PTSD and colleagues uses magnetic resonance imaging (MRI) to measure neuroinflammation and memory and other indicators of cognitive health in veterans. They hope to find ways of forecasting who is most at risk of cognitive decline and accelerated aging due to trauma and chronic stress. Because the pandemic started during the study, it might reveal how the experience affects the aging process. So far, the results, which have been submitted for publication, suggest that people can be caught in a cycle of chronic stress and worsening health. “There is this idea that some people are at greater risk of accelerated aging in response to the pandemic,” Wolf states to Nature, “and it may have to do with the fact that they’ve already got this process underway.”
How Exercise Can Help Ward Off Aging
Knowing that aging is connected to senescence, exposure to infection, inflammation, and chronic stress, individuals can use targeted strategies to combat these risk factors – including exercise. Many articles and review studies discuss “why” exercise can help fight aging and inflammation, but very few discuss the “how” behind the why. Below, we reveal how physical activity can clinically target specific mechanisms in the body to help ward off chronic inflammation, exposure to infection, and the stress that accelerates aging.
Fights Cellular Senescence
As stated earlier, in COVID-19, inflammation emerges through several pathways, including cellular senescence. Senescent cells secrete a mix of signals known as a senescence-associated secretory phenotype (SASP). These signals prompt chronic inflammation, destroy tissues, and encourage nearby cells to become senescent. So how can people protect themselves from this inflammation risk? Exercise, especially muscle toning, can help clear out these cells, making way for healthy new ones. It achieves this by maintaining immune balance through bone marrow homing and increasing the death of senescent T-cells, thus stimulating the production and release of new cells and tissue regeneration.
Builds Immunity & Decreases Inflammatory Cytokines
observed that moderate exercise may have a targeted impact on INF-y (interferon-gamma) and cytokine responses in the bloodstream. Post-exercise cultures showed a significant increase of IFN-γ (a cytokine that induces/modulates immune responses) and L-12 (aids in the activation/regulation of immune cells) compared to their paired pre-exercise samples. It also showed a substantial reduction in the level of IFN-γ after two months of post-exercise inactivity. A more recent study found that patients with systemic lupus erythematosus (SLE) may benefit from clinical aerobic and anaerobic exercise routines. Results found that exercise led to a decrease in specific inflammatory cytokines. SLE is a chronic autoimmune disease that affects multiple organs.
Tempers Toll-Like Receptors
Another anti-inflammatory effect of exercise is its capacity to temper the activation of TLRs (toll-like receptors) signaling. TLRs are a class of proteins that play a vital role in the innate immune system. These receptors recognize pathogen-associated molecular patterns derived from microbes. Research finds that physical inactivity correlates with augmented TLRs activation and, conversely, that chronic exercise has an effect of decreasing cell-surface expression of TLRs on immune cells.
Raises Extracellular Superoxide Dismutase
Extracellular Superoxide Dismutase (EcSOD), a powerful antioxidant released during exercise, can also serve as another weapon in reducing inflammation. A review by Zhen Yan of the UVA School of Medicine showed that aerobic and strength training improves muscle action, causing a rise in EcSOD. This potent antioxidant protects the lung and kidney tissue and reduces inflammation. In addition, EcSOD hunts down free radicals and prevents oxidative stress and endothelial damage, fundamental in disease pathologies, including SARS-CoV-2. Research suggests that even a single session of exercise boosts antioxidant production.
The pandemic is aging us. We need to let this point in history become a prime opportunity for clinicians and the healthcare community to review and improve chronic stress and disease management protocols and interventions – this includes adding exercise. Mounting research suggests that physical activity is not just a benefit or “alternative” measure but a powerful clinical tool in fighting the battle against the stress and chronic inflammation that accelerates aging.
