How Your Genes Could Impact Your Fitness and Health Goals

Box Jumps
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Look at the guy next to you in the gym. He can blast out six-foot box jumps, run a sub-six minute mile, and practically came out of the womb with a six-pack.

You? Your mile time has been north of eight minutes since you took the time trial in high school, you gain a pound just by looking at a Boston crème, and when you do tackle a tough workout you’re out for a week with too-tender muscles. Can you chalk it all up to genetics? Or is that just our favorite excuse?

The answer to both questions: Yes.

“It’s about understanding the genetic information you can act upon and designing workout or nutrition plans that optimize or improve your chances of reaching a certain checkpoint, whether that’s increasing your muscle mass or improving your exercise performance,” says co-founder and CEO of FitnessGenes Dan Reardon, M.B.Ch.B. (UK’s M.D. equivalent) and personal trainer.

When it comes to athletic and physical performance, genetics can be attributed to about 50-60% of the difference between your skills and someone else’s. The other 40-50% comes down to environmental factors like training, diet, and lifestyle habits (i.e. sleep).

Sure, you probably have a good idea what you’re genetically good at and where you struggle. But, do you know what to do about those things to maximize the good and overcome the bad? Click through the following slides and read about which genes could be impacting your “struggle” with certain diet and fitness goals, plus what you can do about them. 

You can also take the FitnessGenes Starter System ($229) test and be one spit swab away from a personalized road map created from 43 of your genetic variations. 

Struggle: always hungry

Hunger and appetite gene – FTO

You’ve probably said it yourself or heard people earnestly say they carry “the fat gene.” While a gene variation of FTO is prevalent in obese men and women, it’s not like the genes are packing on the pounds—but they are making you hungry. If you carry a specific variation, you’re almost biologically hardwired to have more food cravings and become hungry quickly. The culprit is ghrelin, your hunger hormone. 

Some people can eat in the morning and not experience any hunger pangs until lunch or dinner. “They don’t think about food and that’s fine—as long as they’re having balanced meals and macros for their body’s needs and training demands,” Reardon says. But others look at food like Garfield looks at lasagna: with an insatiable hunger.

It’s not that they have lower self-control. Reardon explains: “If you take someone like this and say, ‘You should only be eating three meals a day without any snacks,’ the psychological torture will sink in because they’re hungry.” The scenario that follows isn’t a pretty one. The chances are high you’ll overeat and snack on the wrong types of foods. “These individuals will have deregulation in their eating patterns and won’t get very good results when they stop following the diet and nutrition plans,” Reardon adds. 

The hack: “If you give people with specific FTO gene variations diet plans that are high in fat and protein and low in carbs, they’re a lot less likely to stick to it because they’re not getting the same level of satisfaction,” Reardon says. Long-term strategies for a healthy lifestyle need to be optimized for body composition and genetic dispositions. High-level ghrelin groups have a lot of emotion tied to their eating habits; in short, they need carbs. While a genetic test in addition to your height, weight, and age can tell you the specific ratio of carbs to fat to protein you should be eating, you can take some hunger-reducing measures yourself. Eat good-quality carbs like sweet potatoes, chickpeas, and brown rice; load up on lean protein sources and fiber-rich foods, and make sure you’re sufficiently hydrated. If you have two copies of the FTO gene, eat 5 or 6 small meals a day, reduce your fat intake, and begin a diet you can sustain in the long run. Trial and error is not a good idea; if you give up and the diet is too strict, you’ll suffer metabolic consequences and struggle to stay motivated.

Struggle: Can’t keep weight off

“One person will do diet program X and get incredible results, but when their friends try it, they won’t,” Reardon says. It boils down to genetic variations—across quite a few genes. It may seem unrelated, but the fight-or-flight hormone, adrenaline, plays a role in relaxing skeletal muscle (which delays digestion), cardiovascular (increases heart rate, cardiac output, and regulates blood pressure), respiratory, metabolic, and hormonal systems. 

Adrenaline signaling gene – ADRB2_2
Men with a certain genetic variation of ADRB2_2 are more apt to have a heavier weight, BMI, and fat. If you have it, you’re more inclined to struggle with obesity and have trouble with weight loss plans.

Fat and carb processing – PPARG 
This protein is a receptor that dictates how you store fat and how you break down glucose, which can determine your risk for obesity and diabetes, as well as your response to saturated fats and power-based activities, indicating how easy it is for your body to drop fat and respond favorably to exercise.

Gene for response to saturated fat intake – APOA2
APOA2 plays a role in fat metabolism, insulin sensitivity and obesity. Certain variations are associated with a higher (more negative) response to a diet high in saturated fats and the likelihood of developing obesity. 

The hack: Start by nixing saturated fats from your diet and put your efforts toward high-intensity workouts over steady-state cardio. Turn your workouts metabolic by introducing plyometrics and strength and conditioning HIIT routines. Adopt a sensible diet plan so you have a better chance of dropping weight—and keeping it off. 

Struggle: Stomach discomfort after dairy consumption

Lactate processing gene: LCT

You want your fitness and health, mind and body to work symbiotically—so both benefit. When one piece of either puzzle is out of whack, it can have a domino effect, which is exactly what happens with a lactose intolerance. Whether it’s been caused by genetics or your environment, an intolerance prevents your body from digesting the lactose in milk and other dairy products, which can wreak havoc on your GI tract and tie your stomach in knots pre- and mid-workout. 

The hack:
You probably know if you’re intolerant to dairy, if you can digest lactose, or if you have a sensitivity based on how your stomach feels after eating milk-based products. If you’re intolerant, cut it out completely and begin incorporating non-dairy protein powders and foods rich in vitamin D and calcium. You’re only going to suffer stomach and bowel problems if you try to muscle through it. Be careful if you’re sensitive, and talk to a dietician; if you start weening yourself off dairy, you can make yourself intolerant. 

Struggle: Can’t seem to pack on muscle

There could be a number of reasons you’re having a hard time packing on mass. You could be training or eating ineffectively (or a combination of the two), and then you have to factor in how your genetics balance (or throw off) these external factors. “We can figure out when we look at gene results if you’re a guy who’s got a “fast metabolism” or from a genetic standpoint, an inefficient metabolism. There’s also a bevy of genetic variations that influence muscle, metabolic efficiency, meal timing, and frequency.

Gene for unusual muscle size and strength: MSTN 
Certain variations of this gene determine how you respond to resistance training, and whether you’ll have greater muscle mass and strength. The majority of the population has a genotype (DNA sequence) that elicits normal muscle growth, but there is a “knockout gene” that gives you huge muscles without much training effort. (But you won’t need a test to know if you have this Hulk-like trait.)  

Gene for muscle volume: IL15RA 
IL15RA is linked to the prevention of muscle breakdown and how quickly you can increase your muscle size. Some people carry the genes linked to increases in strength but less muscle size in response to resistance exercise training, while others carry genes associated with larger muscle size and hypertrophy but small gains in strength in response to resistance training.

Genes for regular growth and development: IGF1 + IGF1_2  
The IGF1 gene influences muscle growth and development. Specific genotypes are linked to poor performance and strength.

Gene for strength: ACVR1B
Certain variations mean you’re more apt to have average muscle strength.

The hack: If you’re one of the majority and don’t have the aptitude to gain huge muscles with little effort, your first line of defense is nutrient timing—making sure you’re optimizing your workouts by having energy to train hard and sustain your work—and eating the right kinds of food pre- and post-workout. Even if you do have a fast metabolism, but you’re not timing your caloric intake around your workout, then you’re wasting time and effort. Try to eat within half an hour to an hour before your workout, and 20 minutes after to reap the greatest benefit for your muscles. 

Struggle: Can’t run farther

Genetically, there can be quite a few things setting you back here: how your body reallocates energy to fuel your runs, how well your body clears lactate, your endurance capacity, and Vo2 max.  

Endurance gene – ACE 
Elite endurance athletes (even middle-distance runners, cyclists, and rowers) usually have a specific combination of genes that makes them genetically and naturally better at long-distance events. If you have the power/strength version, endurance is harder for you to build up to.

Fat-burning gene – PPARA
Your body’s ability to switch from fueling your runs on fats instead of carbs combined with your distribution of fast- and slow-twitch muscle fibers can help or hurt your performance. For endurance, you want to have a higher percentage of fatigue-resistant slow-twitch muscle.  

The hack:  Getting better at running long distances comes down to how you periodize your training, prepare for training sessions and events, and recover after these workouts—all of which are relative the above genes. Periodization relates to how you divide and strategize your training plan, and it can strengthen weak points, help you overcome training plateaus, manage fatigue, and build a stronger body. If you’re only logging long miles, you’re not going to see a return in investment because you’re not increasing your Vo2 max or your lactate threshold. To optimize lactate within your body, you need to have a base endurance and incorporate high-intensity training. So, plan tempo miles, track intervals, hill repeats, strength training, and yes, long runs.

Also, if it takes you two days to recuperate from a difficult sprint workout or your legs to feel energized after a really long run, then you need to give yourself the extra recovery time in between difficult workouts to see the results you’re looking for. Make sure you’re fueling your body adequately for long runs, too; if you always exercise in the morning before breakfast, but feel wiped out mid-way through your run, then pre- and post-workout nutrition needs to have a greater emphasis

Struggle: Can’t sprint faster

Gene for speed: ACTN3
Certain variations of the speed gene ACTN3 yield a greater baseline of strength, a protective effect against muscle damage, and an increase in fast-twitch muscle fibers. (Fun fact: One particular version of ACTN3 has been found in nearly every Olympic sprinter ever tested.) If you don’t carry the “sprinter” version of the gene and carry copies of the “endurance” version, your body isn’t able to create rapid, forceful muscle contractions (i.e signal to your fast-twitch fibers) which is necessary for speed and power sports.

“Some people naturally have sprint tendencies,” Reardon says. “West Africans’ limb length, hip mobility, combination of fast twitch and slow twitch muscle fibers, and propensity to respond well to training makes them faster, more powerful sprinters,” he adds.

The hack:
“It’s not about building more fast-twitch muscle, it’s about activating the most fast-twitch muscles you already have, and signalling some slow-twitch muscle to take on fast-twitch tendencies,” Reardon says. If you’re not naturally a sprinter, you need to maximize power training and explosive-type work and minimize activities that optimize slow-twitch muscle. You want to incorporate box jumps, medicine ball slams, kettlebell swings, power cleans, push presses, and jump squats; and when you lift, lift heavy and fast. You don’t want to do long bouts of steady-state cardio, or resistance training with time under tension exercises, or higher reps with a slow tempo.

Struggle: trouble boosting V02 Max

Aerobic capacity gene – PGC1A
Having a high aerobic capacity enables your body to work harder during long bouts of exercise. It’s also a sign of good health. Certain variations enable athletes to have better aerobic capacity and a greater baseline of fitness than non-carriers.

Gene for Vo2 max improvement – CKM
The CKM gene impacts how energy is used in your cells and how well you process oxygen, which is important for speed and endurance. If you carry the “endurance athlete and increased aerobic capacity” genotype, you’re in a good place for ramping up your Vo2 max; if you carry the “weightlifting and combat athletes and lower VO2max” response, you’re gonna have to work harder.

Gene for response to low oxygen – HIF1A
HIF1a controls how your body processes glucose, your metabolism, and the formation of red blood cells. Elite endurance athletes have a genotype that yields a greater increase in VO2 max in response to aerobic exercise training than other carriers. 

The hack:
It all has to do with endurance. Aerobic capacity is your Vo2 max, and how you utilize oxygen. Some people have a greater propensity and respond better to Vo2 max-style training (like hill or sprint intervals and high-intensity circuits). If you don’t, you want to force that adaption. There are also extreme measures like training in a hyperbaric oxygen chamber (or wearing those altitude masks that make people look like Bane from Batman), but penciling in more Vo2-max boosting workouts is the safest bet. This interval workout is actually science-proven to increase your Vo2 max.

Struggle: lagging metabolism

Genes for metabolism – UCP2 + UCP3

A certain genotype is linked to a faster metabolism and a lower risk of weight gain, particularly when combined with exercise, while another is linked to a more efficient metabolism that’s more prevalent in elite endurance athletes.

If you have the “lower metabolic rate” response, your metabolism isn’t as efficient as someone with the “higher metabolic rate” genotype. Because of this, you’re more likely to have a greater BMI and a lower aerobic capacity since UCP3 is involved with how your muscles burn and metabolize fats.

The hack: While we’re all born with a certain metabolic level, you can boost it and get your network of hormones and enzymes burning food to fuel more efficiently. For starters, eat breakfast. A 35g-protein breakfast is linked with greater weight loss, likely because you’re alerting your body to start churning and reducing the odds of snacking on poor-quality foods before your next meal. Make sure your cardio workouts are metabolic, meaning they’re at an intensity where you ramp up the amount of calories you burn during the workout and maximize calorie burn after the workout, and that you’re incorporating resistance training when you lift. Research also shows working out in the morning, without breakfast, can also boost your metabolism.

Struggle: Low levels of testosterone

Testosterone-influencing genes – ESR1 and SHBG1 + SHBG2
Testosterone is essential for building muscle and staying lean since it aids in how nutrients are stored and used. If you genetically have low testosterone, or your lifestyle is lowering levels, you’re more at risk for increased body fat, poor metabolic health, and reduced muscle mass. 

All of the above genes can affect muscle building and your testosterone “score.”

The hack: Reardon says you can alter your daily behaviors to naturally bring testosterone levels back up. Lose weight, eat tesosterone-boosting foods and a healthy diet, lift heavy, complete HIIT-style workouts, take magnesium supplements, and get adequate sleep. 

Struggle: Can’t sleep through the night

Gene affecting sleep cycling: Circadian Locomotor Output Cycles Kaput (Clock) gene
Sleep duration and quality have a huge influence on your recovery, ability to build muscle, lose weight, perform at your best, and many, many more mental facets. Many gene variants have been reported to affect the sleep cycle or the circadian clock. If you carry any genetic variants associated with a disturbed circadian rhythm paired with whether you identify as a morning bird, night owl, or somewhere in between there’s an optimal time for you to exercise. 

The hack: If you don’t get a genetic test, use a sleep monitoring app or wearable fitness tracker to determine whether you have a light, moderate, or severe likelihood of sleep disturbance (i.e. how often you’re restless and wake up throughought the night). If you have moderate to severe sleep disturbance, let yourself naturally wake up during the weekends, and make sure your bedroom is dark, quiet, and cool. If you had a rough night of sleep, recharge and take a 10-20 minute nap in the middle of the day; it’s been shown to be beneficial for performance later in the afternoon and reverse some of the negative effects of sleep deprivation.

If you’re an early bird (you wake up around 6 a.m.), the best time for you to work out is between noon and 4 p.m. If you’re in between being an early bird and a night owl (you wake up naturally just before 8 a.m.) your athletic performance peaks around 4 p.m. And if you’re a night owl (you typically wake up just before 10 a.m.) your muscle and athletic peak is around 8 p.m.

Struggle: Need long recovery time

Inflammation and recovery gene – IL6
IL6 is released from contracting muscles and is thought to protect against muscle damage and improve recovery. There’s a variation that has a protective role against muscle damage following powerful contractions, and people with this genotype typically have a lower waist circumference and BMI, and better improvements in VO2 max following 8 weeks of training. But if you have the lower IL6 expression, you’re more prone to greater weight gain if you’re not leading a healthy lifestyle and a harder time recovering from exercise.

The hack: If it takes your body a few days to clear the inflammation after a grueling workout, try to speed the process by getting plenty of rest, hydrating, icing, and foam rolling. Check out these 10 tips. 

Struggle: Fatigue sets in early during workouts

How quickly your body clears lactic acid determines the onset of fatigue when you exercise. 

The fatigue gene – MCT1
If you have the “slow lactic acid-clearing” genotype, your muscles have a lower capacity to clear lactic acid, speeding its accumulation and the onset of fatigue. (This genotype is found more commonly in endurance athletes who usually have more slow-twitch fibers and greater fatigue resistance.) 

The hack: If you’re tiring quickly in workouts, you may need to reduce the amount of weight you’re lifting and slow your movements down until you get stronger. Give yourself ample time to recover in between reps, sets, and workouts. Always complete a proper warmup so you’re not reducing your range of motion, and work on building your aerobic capacity. Increase your endurance with interval training; the oxygen boost will keep your muscles working for longer periods of time and prevent lactic acid buildup. Prioritize your hydration and nutrition, too. If you’re starving yourself before workouts, you’re sapping all the energy you need to perform.

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