Genetic Testing for Runners
We all know that runner or athlete who just seems naturally gifted. No matter how hard they train, they always seem to come out on top on race day. But how much do genetics truly play a role in determining athletic performance?
In the last few decades, huge advances in scientific genetic technology and research have thrust an entire new world of elements into the fingertips of consumers. It’s now affordable to have your entire genome mapped with a quick mail-in sample of saliva or a cotton swab to the cheek. This now booming industry (we must remember that it IS an industry) has been an increasingly popular avenue for tools in customized health and fitness information. Combine that with the pharmaceutical industry and supplements which are often (controversially) recommended by outside sources on the basis of genetic results, and it’s no surprise that dozens of genetic testing companies have turned up overnight.
Genetic Testing for Athletes
“23 and Me” is one of the most widely known companies, and they offer mapping of your entire genetic sequence, which includes information on ancestry and (optionally) on health indicators as well. Another popular company is DNA Fit, which advertises specific testing packages for Fitness and Diet, for Sports, and for Wellbeing. The Sports category is advertised to give you information about categories like power and endurance, sports injury resilience, recovery speed, recovery nutrition, VO2 max, and fitness genotype breakdown.
Many companies offer specifics like predominance of fast vs. slow twitch muscle fibers, the amount of oxygen delivered to muscles, your personal likelihood of having healthy collagen (the elastic building block of tendons and ligaments, which is often affected with achilles and patellar tendon overuse injuries in runners). The information from genetic testing often shows risk factors or predispositions to certain types of diseases, and can also help you determine your bodies’ own individual potential for detoxification. Some companies delve more deeply into genetic markers that may indicate your ability to lose weight, respond to certain diets, or process certain types of foods. And the list goes on…
This is certainly an attractive bunch of data for runners. But is this information really worth all the hype? Does it really have the potential to predict the best customized plan for aspects of training and racing, or supplementation? I decided to find more research on this area.
What does the research say?
When it comes to athletic superiority measures, several studies have looked at the ACTN3 gene, which is supposedly linked to elite sprinting performance. However, research has not supported this gene as being the stand-alone indicator of fast twitch muscle performance and power output. In fact, one study found that Jamaican sprinters and east African distance runners had no significant difference in the ACTN3 gene.
When it comes to general measures of health and wellness, studies find that similarly there’s not a single gene that has the ability to predict anything with precision. When clients get their genetic results back, many of the companies report SNP’s (DNA sequence variations) or mutations with certain genes that read on paper as that person have a high susceptibility for things like heart disease and cancer. But before you go screaming for the hills and preparing your burial plot… most experts strongly encourage you to “take it all with a grain of salt.”
There are so many things in this world that only react or result poorly when certain factors all line up at the same place at the same time. Take the basic act of baking a gluten-free cake, for example. In order to get a finished product that meets our desires, we must combine exact and correct amounts of certain ingredients in order to have it stick together like a “real” cake in the absence of gluten. If you try to make if from scratch and forget the extra baking soda or ingredients like guar gum, xanthan gum or gelatin, it will often be a crumbly disaster. Our genetic mutations are no exception, and it’s believed that only the “perfect storm” combination of altered genetics, in conjunction with environmental alterations, lead to disease states.
How should we interpret and use genetic testing results?
So, we are faced with an interpretive dilemma when reading these genetic test results. Sure, they may indicate that your body is more likely to be obese, more likely to be better at endurance sports, or more likely to need extra supplementation of something like folate or B vitamins. However, it is VERY important to remember that the human body is very complex and that a number of factors interact to promote the environment for both performance and disease states. Medical experts recommend a number of guidelines to help you in this area:
- If you’re perfectly healthy and feeling well, the testing may not offer a lot of useful information that can be applied to your training or fueling. However, if you feel like you’re eating well, resting well, and training well, and yet are still struggling with overall wellness, the test may guide your doctor into what type of testing they could do to help you determine any diagnostic or nutritional needs. It’s recommended you seek out a functional medicine doctor or naturopath who can further guide you in addressing the entire big picture with both labs and genetic results.
- Never based your supplementation on genetic testing. Combine the information with actual blood or urine test results and review it with a doctor if you suspect you are deficient in something or have an area that is not performing well (ie- detoxification).
- If you get genetic testing, don’t read too much into the results. Look at it as an interesting bit of information to add to the factors that you already know about yourself. It is NOT equivalent to diagnostic information, nor does it possess predictive qualities.
Don’t forget about Environment!
One of my favorite quotes is “Genetics loads the gun, environment pulls the trigger.” While we may not be able to control our genetics, we can certainly control our environment to a certain extent. Making time for regular practice of stress-relieving techniques like yoga, meditation, or breathing exercises plays a large role on our body’s overall state of stress and expression of certain genes. Psychological well-being and amount of sleep are other important internal factors, particularly with athletes. External factors also greatly affect our genetic expression, from everything like altitude, air, water, light, sound, pollution/environmental factors, food, and even EMF (electromotive force, or voltage developed by a source of electrical energy). Perhaps in future years the experts will have more figured out about genetics and athletic performance. (Remember that genetic mapping is all a relatively new science that is only in its infancy stages).
Take Home Message
This is a very complex discussion that is difficult to sum up concisely. This article only covered the tip of the iceberg, without getting too technical. “Methylation” is another hot genetics topic that is subject to much of the same debate. There are many great web and podcast resources out there, but be wary of media that is put out there by companies who perform genetic testing, as they are obviously biased.
In summary, genetic testing may be of benefit for athletes who feel like they are not performing or recovering to their full potential despite taking all of the necessary steps needed. When combined with doctor advice and actual medical testing, genetic testing can be a great tool for unlocking more insight into an individualized diet, supplement and training plan. However, a degree of caution should be exerted when interpreting the genetic results alone for disease risk factors and supplement advice, as the physiological processes as they relate to genetics are ultimately strongly influenced by a plethora of other biological and environmental factors.