Could DNA Dictate Your Best Workout?

Want guaranteed results? Consider your phenotype.

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Contrary to what magazine covers would have you believe, there is no magic workout that works for everybody. Customization is key, and over the years that word has become commonly used to describe various types of program development. We exercised for our body shape, blood type, personality, and even astrological sign, but recently the conversation has taken a more scientific turn. The latest approach: exercising for your phenotype. And it may be more than buzzworthy. Scientists and industry insiders say we could have finally cracked the body betterment code.

Equinox Q
Equinox Q

While still somewhat in its infancy, DNA testing is beginning to be used in top facilities around the country to inform trainer-prescribed exercise plans for both aesthetic and wellness purposes. And the testing itself requires nothing more than a simple cheek swab and subsequent lab analysis.

"By determining a client's genetic expression, skilled fitness professionals can better understand his or her unique physiological response, and design a program that best supports the goals," says Geralyn Coopersmith, an exercise physiologist and head of the Equinox Fitness Training Institute, Equinox's in-house education program for all of its personal trainers. At E, a private training facility within Equinox clubs in Los Angeles and New York City, top-level coaches work with a company called Existence Genetics to process DNA testing and inform training protocol. The genetic test costs $500. That does not include personal training fees.

The focus there is more about disease prevention, but the residual effects of overhauling your physical health tend to include reshaping muscles and losing fat. "Everything is actionable," says Matthew Berenc, the personal training manager at the Century City club in Los Angeles who handles the program. "The future of health and fitness is not just being reactionary, but taking proactive steps."

No matter what the goal, the crux of the approach is to understand what your phenotype is and what that means for how your body responds to specific training. "Just as some athletes are literally made for endurance running or sprinting and are trained accordingly to enhance those natural-born inclinations, we have these existing genotypes just waiting to be stimulated in a specific way in order to best produce results," Coopersmith says.

We are usually either dominant in aerobic or anaerobic physiology or sit somewhere in the middle. The main differences lie in what type of muscle fibers we have and how quickly those fibers contract, the type of fuel our bodies are inclined to convert into energy, and how we use oxygen under exertion. For example, someone with an anaerobic-dominant physiology uses more fast-twitch muscle fibers and produces more powerful contractions; he or she might benefit from intense plyometric training that elicits those types of responses from the body, whereas that approach could fall somewhat flat on an aerobically-dominant phenotype.

Specifics aside, overall, the message is a positive one. The phenotype theory gives hope to those frustrated by the all-too-common lack of results. Even without formal testing in place, most experts would agree that if after six weeks of training you're not reaching the proper benchmarks for improvement, it might be time to change course. It's also strong evidence for what industry veterans have been saying forever: Change up your routine. For example, incorporate both longer, steady state cardio and shorter, sprint interval sessions into your training (which you should be doing anyway). Or alternate body-weight training sessions with dumbbell days. Do what you have to do to elicit the right response from your unique physiology and results are quite literally guaranteed.

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Liz Miersch is editor-in-chief of Q, By Equinox. A former fitness editor at Self, she has written for magazines including Fitness and Details. Liz admits a newfound obsession with power yoga— specifically arm balances. Get your daily guide to fitness, life, and style at Q, a blog by Equinox.