by Nicholas Crown
She has “good” genes. He has “bad” genes. We all too often build a genetic roadblock in the way of our most important goals. Sure, genes are genes are genes. However, recent studies have shown that we have tremendous power over the expression of our genes by making positive lifestyle choices. Dad may have gone gray early, but it doesn’t mean that you will. Mom may have even suffered from dementia, but you’re taking measures to avoid this fate, right? Your diet, fitness, and mental condition will dictate how you respond to the aging process and even various, serious illnesses.
Studies continue to reveal: no one is a certain victim to family history. In fact, your known, genetic weaknesses should become motivational fuel. Here’s your wakeup call. Genes are officially a terrible excuse for shrugging off the treadmill. The message is twofold: one part carpe diem and one part applied science. First off, what exactly is epigenetics? From the Greek prefix, epi-, it’s anything that is outside of, around or on top of genes. In other words, changing the expression of genes without actually altering your DNA. It’s the effects on your cellular or physiological state from external factors—like environment, lifestyle, and stress.
Interestingly, these modifications are heritable. Meaning, your morning workout isn’t just benefitting your health directly, but potentially the health of your future offspring. This all comes down to DNA methylation (1). In a nutshell, you lose methyl deoxycytidine as you age, which is responsible for cellular differentiation and maintenance (2). Similarly, this process promotes tumor-suppressing genes and positive metabolic function. Exercise alters this pattern of DNA methylation. While the exact scientific pathway is a bit more involved, this general concept will weave throughout our discussion. As the clock ticks, wear and tear occurs on the cellular level.
As a side note, you may already be familiar with epigenetics. There has been extensive research done in epigenetics in early childhood development, heritability of addiction, anxiety, and depression. You’ve heard how alcoholism may “run in a family” for generations or how depression may be common between two family members. Things really get interesting when applied to fitness. As you can see, the power of fitness and strength training extends far beyond aesthetics. Without falling victim to melodrama, this discussion may prove a lifesaver.
The Fitness Time Machine
Ageing is a brutal process. As men, our energy, testosterone, collagen, and bone density (just to name a few!) will decline over time. Not exactly a fairy tale ending. We, however, have the ability to slow this process and even reverse some damage. The time machine awaits; it’s just not as easy as pressing a button. As mentioned above, DNA methylation decreases with age; vastly different from newborns to centenarians (3). Remarkably, this loss is slowed by exercise. One recent study shows that adults who exercised thirty minutes or more per day had significantly more DNA methylation than the control group of sedentary individuals (4). Repeated, strenuous exercise has shown the most impact. Keep in mind; this is the routine grind, not a weekend jog.
Furthermore, as we age, telomeres at the end of our chromosomes gradually shorten. These structures are pieces of redundant, genetic code that protect from cellular damage; a DNA shield, so to speak. Occasionally, telomeres can produce non-coding RNA, which as an additional layer of stability. As you exercise, your body increases the amount of non-coding RNA (5). As telomeres become more stable, they’re less likely to be subject to the shortening as we age. You’re building an extra barrier against genetic mutation.
Improve Your Resistance to Cancer
Perhaps the most notoriously malicious disease of all, cancer, is also influenced by DNA methylation patterns. Consistent exercise increases your genetic resistance to tumor growth while simultaneously suppressing oncogenes, or genes that have the potential to turn tumorous (1). Exercise reduces the likelihood of epigenetic mutations, in some instances actually reversing the damage. Interestingly, a common marker for cancer is the methylation of certain tumor suppressing genes (6). Fitness is sound preventative “medicine” especially for those at elevated risks.
Another consideration is how exercise increases good stress, or eustress, on the body. Eustress increases the expression of tumor suppressant genes (7). The vital p53 protein, a regulator of cell growth, is also coded by this gene, which advances the anti-cancer effect. In women, exercising patients were observed as having a 60% reduction in risk of breast cancer death as compared to a limited-exercise group (8). The tie-in of fitness walks (or marathons) among many breast cancer fundraising organizations isn’t just a good idea for improving research; it may actually promote continued health amongst participating survivors.
Metabolic Improvement and Diabetes
When we think of exercise, especially aerobic activity, we think of burning fat and increasing your heart rate. Logically, this should improve your metabolic function at rest as your body becomes more conditioned to strenuous activity. Looking closer, on a genetic level, exercise has a hand in the expression of genes associated with your metabolism. When you exercise, you activate regulatory genes responsible for muscle repair and growth.
Digging deeper, MicroRNA also plays a role. MicroRNA’s can interfere with blood flow, genesis of blood vessels, and cause inflammation by blocking mRNA. Broadly, exercising reduces the MicroRNA count in our muscle tissue. A proper fitness regimen of resistance training and healthy diet has show to reduce MicroRNA (9). This means the growth and regulation of skeletal muscle with improved blood flow.
As for diabetes, several genes involved in glucose transport and metabolism and energy metabolism are subject to hypermethylation (10). Mitochondrial DNA, in the powerhouse of a cell, also falls victim to the methylation of these genes. Exercise acts as a reversal to the process, improving cellular function as well as reducing touchstone diabetic symptoms. While not a panacea, exercise is an important tool in combatting diseases, especially as a preventative measure.
Fitness is a lifestyle choice. It’s a grind and certainly takes dedication. However, if the obvious benefits (looking good on summer vacation) weren’t enough to pull you out of your desk chair and onto the bench press, the subtle epigenetic effects certainly will. So, to be blunt, if the quality of your life is important to you as you age, hit the gym. After all, we all want to age as gracefully and as slowly as possible.
References
1. Handy, D. E.; Castro, R.; Loscalzo, J. (2011). “Epigenetic Modifications”.
Circulation.
2. Wilson, V. L.; Smith R. A.; Ma S.; Cutler R.G. (July 25, 1987). “Genomic 5-
methyldeoxycytidine decreases with age”
3. Heyn, H; Li N; Ferreira HJ; Moran S; Pisano DG; Gomez A; Diez J; Sanchez-Mut
JV; Setien F; Carmona FJ; et al. (June 26, 2012). “Distinct DNA methylomes of
newborns and centenarians”.
4. Zhang, F. F.; Cardarelli R; Carroll J; Zhang S; Fulda KG; Gonzalez K;
Vishwanatha JK; Morabia A; Santella RM (Mar 2011). “Physical activity and
global genomic DNA methylation in a cancer-free population”. Epigenetics.
5. Werner, C.; Hanhoun M.; Widmann T.; et al. (August 5, 2008). “Effects of
physical exercise on myocardial telomere-regulating proteins, survival
pathways, and apoptosis”. J Am Coll Cardiol.
6. Coyle, YM; Xie XJ; Lewis CM; Bu D; Milchgrub S; Euhus DM (February 2007).
“Role of physical activity in modulating breast cancer risk as defined by APC
and RASSF1A promoter hypermethylation in nonmalignant breast tissue”.
Cancer Epidemiol Biomarkers Prev.
7. Sanchis-Gomar, F.; Garcia-Gimenez, J. L.; Perez-Quilis, C.; Gomez-Cabrera, M. C.;
Pallardo, F. V.; Lippi, G. (December 2012). “Physical exercise as an epigenetic
modulator: Eustress, the “positive stress” as an effector of gene expression”. J
Strength Cond Res.
8. Zeng, H.; rwin, M. L.; Lu, L.; Risch, H.; Mayne, S.; Mu, L.; et al. (May 2012).
“Physical activity and breast cancer survival: an epigenetic link through
reduced methylation of a tumor suppressor gene: L3MBTL1”. Breast Cancer Res
Treat. 133
9. Ntanasis-Stathopoulos, J.; Tzanninis, J-G.; Philippou, A.; Koutsilieris, M. (June
2013). “Epigenetic regulation on gene expression induced by physical exercise”.
J Musculoskelet Neuronal Interact.
10. Ling, C.; Groop, L. (December 2009). “Epigenetics: A Molecular Link Between
Environmental Factors and Type 2 Diabetes”. Diabetes
