Getting Active Slows Your Cells Aging
Jessica Caterini, B.Sc (Hons), M.Sc.
We know that exercise provides a host of benefits to our bodies by improving the function of our heart and lungs as well as improving our muscle strength. But what if there was an ‘anti-aging’ effect that exercise could have on our DNA? Scientists have discovered structures protecting the end of our genetic material called ‘Telomeres’ that may hold the key to cellular aging. These components of DNA protect the ends genetic material by making sure that different components of DNA do not unravel and become stuck to each other. Telomeres shorten as our cells divide as a normal process of aging. This process is associated with increased cancer risk, and higher mortality. The good news is that numerous researchers have demonstrated that physical activity reduces the shortening of telomere length as we age!
Stress in daily life can shorten telomere length over time, but exercise stress may be an effective buffer for slowing telomere shortening and cellular aging. A study in PLoS One examined the role of exercise for moderating stress-induced telomere shortening (Puterman et al., 2010). 63 post-menopausal women completed a perceived stress scale, recorded their physical activity (PA) levels, and had measurements taken of the telomere length in their white blood cells. The researchers found that exercise significantly moderated the effects of perceived stress on telomere length! However, dosage was important in this relationship; there is a point at which increasing PA is no longer associated with shorter telomeres. Participants did not have any increased benefits in PA reduction if they exercised more than 40 minutes a day over three days. When you are stressed and busy you are less likely to exercise- but this research shows that moderate exercise during your most stressful days confers the greatest benefits to longevity and healthy aging.
It is important to note that dosage of exercise can have a demonstrable effect on telomere length. When energy expenditure is divided into quartiles in older adults, moderate levels of PA (2nd and 3rd quartiles) are associated with longer telomeres. However, the highest levels of PA (10-14 hours/week) are associated with telomeres of length similar to those of sedentary older adults (Ludlow et al, 2008). This relationship between sedentary behaviour and shorter telomeres was recently confirmed in a study examining the effect of sitting time on telomere length in participants aged 68 years (Sjoren et al., 2014). Researchers observed a strong relationship between increasing time spent sitting and shorter telomere length. Therefore, limit your sitting time to reduce telomere shortening, but also take appropriate recovery between your workouts and do not over-train!
The Berlin Aging Study was one of the largest studies to examine the relationship between telomere length and physical activity levels (Sabenroth et al., 2015). The study looked at 815 participants across different stages of life, and compared their participation in different sports with the length of the telomeres in their white blood cells. Longer periods of physical activity participating in intensive sports was significantly associated with longer telomeres. The good news is that the greatest effects of physical activity participation on telomeres were seen in adults over 42 years of age! Even better, physical activity performed when you are a young adult (between 20-30 years of age) had no relationship with telomere length! So don’t fret if you were inactive when you were young; if you start now you can still harness the effects of exercise on slowing the rate at which your telomeres shorten. Increasing your levels of physical activity now can hold the secret to slowing aging in your cells. It’s never too late to start getting active and improving how you age!
Ludlow, A. T., Zimmerman, J. B., Witkowski, S., Hearn, J. W., Hatfield, B. D., & Roth, S. M. (2008). Relationship between physical activity level, telomere length, and telomerase activity. Medicine and science in sports and exercise,40(10), 1764.
Puterman, E., Lin, J., Blackburn, E., O’Donovan, A., Adler, N., & Epel, E. (2010). The power of exercise: buffering the effect of chronic stress on telomere length. PLoS One, 5(5), e10837.
Saßenroth, D., Meyer, A., Salewsky, B., Kroh, M., Norman, K., Steinhagen-Thiessen, E., & Demuth, I. (2015). Sports and Exercise at Different Ages and Leukocyte Telomere Length in Later Life–Data from the Berlin Aging Study II (BASE-II). PloS one, 10(12).
Sjögren, P., Fisher, R., Kallings, L., Svenson, U., Roos, G., & Hellénius, M. L. (2014). Stand up for health—avoiding sedentary behaviour might lengthen your telomeres: secondary outcomes from a physical activity RCT in older people. British journal of sports medicine, 48(19), 1407-1409.