The secret to exercise can be told in a single phrase: keep going, don’t stop. It’s better to be active all your life at any level, including mild activity, than to play sports in high school and college, only to sit back as the years advance. Consistency is the main goal, not breaking a sweat. But this takes a conscious choice, one you are willing to stick with. The good news is that the more you keep on moving your body, the more you’ll want to. Physical activity becomes a habit you adapt to rather quickly, not to mention that it helps create new pathways in the brain.
Modern life has made exercise a blessing and a curse. The blessing is that we are no longer slaves to backbreaking physical labor; the curse is that the blessing has gone too far. Modern life for most people is physically too soft, yet despite the price our bodies pay, we seem to prefer it that way. Given a choice, most people choose
Sitting still instead of moving around
Pleasurable distractions (TV, video games, the Internet) instead of playing sports
Mental work instead of physical work
Letting machines instead of muscles perform physical tasks
Letting their children spend more time on the computer and less time playing outside
These are all modern choices, and the trend hasn’t stopped moving in their direction. As long as it does, the drawbacks of a sedentary life, such as increased obesity and type 2 diabetes, will plague society, while the benefits of exercise—in terms of cardiovascular health, avoidance of some types of cancers, and improved mental status—will be missed opportunities. As of 2013, only 20 percent of American adults got the recommended amount of regular exercise, which is 2.5 hours of moderate aerobic exercise per week or half that time spent in vigorous aerobic exercise. Someone between the ages of eighteen and twenty-four is twice as likely to exercise as someone over sixty-five—31 percent versus 16 percent—even though it’s evident that the two groups that benefit the most from physical activity are the very young and the very old.
For our ancestors, rest was a luxury; for most of us, finding the time to go to the gym is the luxury. At the turn of the twentieth century, around 80 percent of the calories expended to run a farm still came from the farmer using his muscles. This was true despite the invention of farm machinery and the widespread use of horses to draw plows, harvesters, and wagons. Such a life, where physical activity was hard and constant, was how we evolved. Our bodies are well adapted to much more activity than you’d suppose. There is evidence that primitive hunter-gatherers had a life span as long as seventy years. What shortened their lives were external conditions—disease, childhood mortality, exposure to the elements—not the built-in frailty of the body.
Because most of us don’t have to hunt, gather, till the soil, fork hay into the hayloft, or make our own bread—the list can be extended ad infinitum—there’s almost no essential physical work left. Therefore no matter how often we hear the drumbeat of diet and exercise, good intentions outweigh action. It’s because compliance is so low that we put stress management above exercise in our lifestyle list. More people are more likely to reduce the pressure in their daily lives than to get up out of their chairs and start moving.
We are realists, and we know that scolding will never motivate people to change their ways. Guilt only leads to unused gym memberships. Neither will the balance of pain and pleasure serve as motivation. Anyone who enjoys exercise is highly likely to have been running, lifting weights, or playing sports since childhood. Their bodies are conditioned to it, and the feedback loop that leads to the runner’s high or to the “good tired” of a workout is a source of pleasure. For someone who isn’t in the habit of exercising, though, the reverse is true. Exercise affects the body like physical labor, leading (at the beginning) to fatigue and sore muscles. The body of someone who doesn’t exercise is habituated to sitting still, the ill effects of which are mostly long term. It can take years before the reality of heart disease, type 2 diabetes, and excessive weight actually begins to dawn.
Our goal, then, is to provide easy choices that can change the feedback loop, which means that a little activity leads to wanting more. In addition, the recommended changes must be maintained for a lifetime. Getting active in spurts with long periods of no activity in between isn’t good for you. Adaptation comes naturally when it’s regular and steady. Better to walk up a flight of stairs every day than to shovel snow off the driveway six times a winter.
Reading the menu: As in every section on lifestyle, the menu of choices is divided into three parts, according to level of difficulty and proven effectiveness.
Part 1: Easy choices
Part 2: Harder choices
Part 3: Experimental choices
Please consult this page in the diet section if you need a refresher on what the three levels of choice are about. You should make one change per week total, not one from each lifestyle section. Remember, too, that whatever choices you make are meant to be permanent.
• Get up and move around once an hour.
• When taking an elevator, take the stairs to the second floor before pressing the button.
• Do your own housework instead of hiring a cleaner.
• Take a brisk walk after dinner.
• Choose the far corner of a parking lot (as long as it’s safe and well lit).
• If you already walk your dog every day, make the walk longer and brisker.
• If a destination is less than half a mile, walk instead of drive.
• Buy an exercise step and use it for 15 minutes every day as you watch TV or listen to music.
• Go outside for 5 to 10 minutes three times a day.
• Take up gardening, golf, or a similar activity that you actually enjoy.
• Set aside 5 to 10 minutes a day for calisthenics.
• Do more than half the chores around your house.
• Work with light weights as you watch TV.
• Acquire more-active friends and join them in their activities.
• Devote half of your lunch hour to exercise.
• If you take children to the park, play with them instead of watching.
• When using an elevator, take the stairs to the third or fourth floor before pressing the button.
• Plan a shared exercise activity with your partner or spouse twice a week.
• Buy an exercise step and use it for at least 30 minutes every day as you watch TV or listen to music.
• Resume a sport you used to love.
• Do 5 to 10 minutes of calisthenics twice a day.
• Walk for a total of 3 hours a week.
• Do all your own yard work.
• Volunteer to help the needy with housecleaning, painting, and repairs.
• Take hikes every weekend in good weather.
• Use a trainer at the gym.
• Join an exercise class.
• Take up yoga (see this page).
• Lead a hiking group.
• Train for a competitive sport and keep at it.
• Find a regular exercise buddy.
• Take up tennis.
The easy choices on the menu are quite easy. They would have to accumulate quite a lot to equal the official recommendation of 2.5 hours of moderate aerobic activity a week, combined with some additional time at weight training. But those recommendations might as well come from another planet if you lead an inactive life. The good news is this: Getting up out of your chair brings the most benefit. Moving away from a completely sedentary life is the major step in preventing the bad effects of getting no exercise. The risk of disease rises sharply as you age if you don’t move around. Drastic inactivity eventually leads to a 30 percent higher mortality rate for men and double the mortality rate for women. The “new old age,” in which seniors remain active and vital well beyond sixty-five, reversed one of the unhealthiest trends in social life.
The more activity you add, the better your body will respond. If you go from jogging a mile to running a mile, the good effects will increase. What your heart, brain, circulatory system, blood fats, and blood sugar need most is some activity, after which you can think about adding more.
In middle age, getting physical decreases the risk of chronic illness. Statistical measurement has proved the point over and over. Unlike other risk factors, however, exercising is more than statistical. It improves every individual life, at every level of activity. In very old people, eighty and above, weight training for a few minutes with minimal effort (using only a five-pound weight, for example) can double or triple muscle tone.
Our focus isn’t on how much weight you can lift or how fast you can run. We want to level the curve so that physical activity isn’t mostly for the young, with a sharp falling off in middle and old age. Leveling the curve is much more important than being really active in your youth and inactive in old age. Your body adapts to what you do all the time, not what you do every once in a while. This is also the secret for making exercise pleasurable—the feedback loop between muscles and brain gets enlivened the more you use it. Just like a biceps or abdominal muscle that atrophies with disuse, the body’s feedback loops need to be utilized, and the more messages they transmit, the livelier they become.
Of course, we hope that you will move on to the harder choices on the menu. Give it time. If you spend two months taking the stairs to the second floor before pushing the elevator button, the next step—walking to the third or fourth floor—becomes effortless. But if you decide tomorrow to walk to the fourth floor, you are likely to feel exhausted, and your body will get the message “This is work.” It’s not the right message, not if you intend to make taking the stairs a pleasurable choice.
If we had to choose the single activity that does the most for body and mind together, it would be yoga. The correct term is Hatha Yoga, which is only one limb of the ancient tradition of Yoga, which has eight limbs in all. The others have to do with mind and behavior, but the body cannot be excluded in the pursuit of higher consciousness. In Sanskrit Yoga means “union” and is related to the English word yoke. As mysterious as the concept of enlightenment may seem, Yoga makes sense in its goal of bringing the mind, body, and spirit into harmony. Each position (or Asana pose) that’s taught in Yoga is about focusing the mind to direct the flow of physical energy in the body.
Not that the two are separate. When consciousness moves, so does the energy. The teachings of Hatha Yoga can be quite subtle and even esoteric. The flow of life energy (Prana) that is regulated by the breath can be trained in exquisitely precise ways. The flow of life energy connected directly by the mind (Shakti) is even more precise and exact. It’s taught that a single syllable in a mantra, for example, has influences that extend from mind and body throughout the entire environment.
The topic is so fascinating that we are devoting a section to consciousness as the pivot between everyday well-being and radical well-being. Hatha Yoga is a step in that direction. It improves body awareness, gets you back into physicality, sharpens your focus, and tones your muscles at the same time. Ironically, the practice is taken up mostly by men in India and mostly by women in this country. In India, the pursuit of higher consciousness is open to everyone in theory, but in practice women have been excluded. In America, men typically disdain yoga because it’s not weight training or aerobic. Both attitudes are skewed and need to change.
At the moment, the epigenetics of exercise is so new that few studies exist, but this hasn’t stopped genetics from making its biggest contribution. We now know that being holistic isn’t just someone’s personal preference—it’s necessary for everyone. Because hundreds and sometimes thousands of gene activities are changed through lifestyle choices, exercise can’t be isolated from diet or diet from stress. This shift has enormous implications.
For example, health care providers used to minimize the health risks of leading a sedentary life. If you asked a physician thirty years ago what was wrong with having no physical activity, almost the only thing he’d come up with is disuse atrophy—the wasting of muscle tissue when a muscle isn’t being used. Now we realize that a broad range of mind-body problems arise from a sedentary lifestyle, spanning heart disease, anxiety and depression, hypertension, and diabetes. The affectionate image of a plump grandma sitting in her rocking chair has become an image of bad health and decreased well-being.
These ill effects can be gleaned by looking at statistics for the general population, but epigenetics will one day be able to fine-tune an individual’s personal risk. Sometimes what’s true for a large number of people isn’t true for you the individual. Across the population it’s a well-established fact, for instance, that inactivity leads to obesity through the simple formula that expending fewer calories than you take in will develop body fat. But as we’ve seen, the old belief “calories in, calories out” has been revised.
To get at a possible genetic link between physical activity and body fat, a study carried out at Lund University in Sweden investigated the effects of physical activity on epigenetic gene modifications in fat cells. The researchers found that exercise led to epigenetic shifts in gene activity (via methyl marks) that affected fat storage in the body. They looked at the genomes of fat cells in twenty-three healthy men aged thirty-five before and after attending aerobics classes for six months, roughly twice a week. They found that exercise led to epigenetic changes in seven thousand genes, many of which led to genome-wide changes in DNA methylation in fat cells, shifting activity to enhance fat cell metabolism.
Methylation can remove methyl groups if they are properly exposed by histones, which work hand in hand with DNA in epigenetic modification by either exposing it to epigenetic marks or burying it—in essence, the switch is either made available or not. With exercise, methylation patterns change: some genes are silenced by methyl marks and others are unsilenced by demethylation. These are complex changes, but in essence, switches are turned off (downregulated) for pro-inflammatory genes while anti-inflammatory genes are switched on (upregulated). No doubt the mounting evidence about lifestyle changes will expand the anti-inflammation story across the entire mind-body system.
Weight loss is a common goal when people begin to exercise, but exercise leads to mixed results. The number of calories consumed through physical activity isn’t as great as people suppose. A slightly brisk walk burns 280 calories per hour. Hiking, gardening, dancing, and engaging in weight training burn around 350 calories per hour. At 290 calories per hour, bicycling under 10 miles an hour burns off little more energy than walking. If your physical activity is vigorous—running, swimming, or aerobics—energy consumption increases to between 475 and 550 calories per hour. But even playing a vigorous game of baseball burns off only 440 calories per hour. Considering that a medium-size blueberry muffin contains 425 calories, there’s good reason why exercise alone isn’t the solution to weight loss.
However, if we take a holistic perspective, so much else changes when you become physically active that calories diminish in importance. In one study, overweight people were divided into three groups. The first group ran a mile, the second group jogged a mile, and the third group walked a mile. At the end of the trial period, the group that lost the most weight was the one that walked. One reason is metabolic. Once you break into a sweat, your body goes from aerobic metabolism, which burns calories, to anaerobic metabolism, which doesn’t. So there are instances in which less pain means more gain. Keeping exercise light but constant seems to be the key. Yet even this bright note is offset by the fact that exercise, being physical work, can make you hungrier. In addition, heavier exercise builds muscle mass, which is heavier than body fat. We’ve considered these variables and keep coming back to the basic principle that you should make easy changes and keep on going, not stopping.
Very little has been discovered about the epigenetic effect of trying to lose weight. On the one hand, it appears that adult obesity goes back to childhood and adolescent experiences that extend into later years. Methylation may have imprinted bad habits and overeating into a person’s gene activity. There is also the question of how much of an epigenetic influence gets passed on from obese parents to their children. We’ve been citing the data from the Dutch famine of World War II, but that evidence comes from extreme starvation, which then led to genetic modifications that apparently raised the risk of obesity in children, depending on whether their mothers were pregnant during famine times or times of plenty. It’s quite another thing to sort out epigenetic marks according to which cause is at work, since obese parents can easily pass on bad eating behavior as well as epigenetic marks from their own experience before and during pregnancy.
Just as significant may be a Spanish study that took 204 obese or overweight teenagers and put them on a ten-week weight-loss regimen. It’s well known that being obese as an adolescent leads to higher risk for a range of diseases in adulthood, not just the risk for being an obese adult. The program in this study was multifaceted. The teenagers were given personalized diet and exercise programs. They attended weekly meetings that gave them more nutritional and exercise information, along with psychological support.
At the end of the ten weeks, the researchers selected out the subjects who were considered either high or low responders to the program, depending on BMI (body mass index, which looks at the percentage of fat in the body) and the amount of weight lost. Looking at their epigenomes, some strong correlations were found. The high and low responders showed differences in methylation in ninety-seven different sites along their DNA. As reported online at the epigenetics site EpiBeat, there was a link to inflammation. “The involved genes belong to networks related to cancer, inflammatory response, cell cycle, immune cell trafficking, hematological system development and function.”
In five sites the changes were so different that simply by examining the methyl marks there, one could predict who would be a low or high responder to a weight-loss program. The differences increased, the better someone responded to the program. These results offer two possibilities. First, epigenetic profiling may enable us to know in advance who will find it easy or hard to lose weight. Second, we may be able to pinpoint the gene activities that physical exercise promotes.
Making the gene connection more precise solves only part of the problem. It was originally thought that methylation occurred in the womb and lasted for a lifetime. Now it’s realized that epigenetic changes are dynamic, constant, and often very rapid, taking place in twenty-four hours. Chemicals known as demethylases can remove methyl marks, and they have been connected to a specific gene (for fat mass and obesity-related transcript). Variants of this one gene are more associated with risk for obesity than any other genes. As reported by epigenetic researchers at the University of Alabama, Birmingham, it’s thought that the instructions encoded in FTO create a protein that acts as a demethylase. This protein may act to turn off or on the genes that create obesity, although the exact mechanism isn’t known, nor is it known why FTO is related to obesity. But the key finding is that regular exercise “largely erases the increased risk for obesity associated with the versions of the FTO gene. No one then is doomed by their genes,” said team leader Molly Bray.
When it comes to the microbiome, there’s been little study connecting it directly with exercise. One intriguing finding, however, comes from Ireland, where a team from the University College Cork compared forty professional rugby players with a control group of healthy adult males. The athletes were at pre-season training camp, which is a controlled environment—they ate and played together. The investigators looked at blood markers for inflammation that were also connected to immunity and metabolism.
It turns out that the athletes had a much more diverse microbiome. They were also improved over the control group in regard to markers for inflammation, immune response, and metabolism. Although some of the improvement could have been through diet, this seems to be a significant finding, if a very general one, about how gut microbes respond to exercise.
Given the present state of the science, we feel that the best practical course is to rely on demethylation through positive lifestyle choices—in other words, doing what you can today to regulate the genes that are beneficial, with a focus on lowering markers of inflammation. To date, there’s no way to target only the changes related to body weight, but that’s not essential for most people who aren’t significantly overweight. A general program of the kind we’re recommending is the best medicine anyone has yet devised with good science behind it.