Why You Must Exercise
A strong body makes the mind strong.
John Lennon was right: All you need is love—the love of exercise.
Exercise is a key tool for fighting food cravings and changing eating behaviors. When it comes to weight loss, burning calories is helpful, but it is a distant second to the psychological, hormonal and chemical changes that exercise initiates—changes that allow you to gain control over what you eat. Getting physically active is the most powerful tool there is for controlling eating behavior.
Are you an inactive couch potato? Do you hate the idea of sweating? I understand, because I used to be the same way. I was the high school spaz who made the geeks look good and always got picked last when teams were chosen. I sucked at every sport imaginable, yet I now love exercising almost every day of the week. I have about 50 pounds less fat and 20 pounds more muscle than I did two decades ago.
This isn’t “if I can do it, so can you” motivational pablum. I hate that. I just want you to know I have some perspective on what you’re about to go through.
Exercise Is Critical
“Exercise is a critical component of weight loss and weight maintenance,” Dr. Miguel Alonso-Alonso, who specializes in how exercise affects the brain, told me. “We know that. It’s a fact.”
Harvard doctor up there. He says it’s critical. Take heed.
I’ll be blunt. You’d be a fool to ignore exercise as part of your weight loss strategy, because it creates a suit of armor to protect you from the endless temptations of our toxic food environment.
Why am I harping on this? It’s because I’ve been to the bookstore. By my estimation, 80 percent of weight loss books are either only about diet or pay the barest lip service to physical activity. They perpetuate a myth that exercise is torture and sweating is gross. Well, sweating is kind of gross, but you get used to it, and there are breathable fitness clothes that mitigate its ickyness.
Miracle-diet books that promise “no exercise required” are telling people what they want to hear. Instead, I’m going to tell you what you need to hear. (What this will mean for book sales remains to be seen.)
Exercise improves diet, which reinforces exercising, which improves diet, which … creates a virtuous cycle. When it comes to health and fitness, would you rather be in a virtuous cycle, or a death spiral?
A word of caution before you dash off to the gym or the pool or the cross-country skiing trail: while exercise is indeed rewarding, the most important thing to remember when adopting an exercise regimen is to avoid the trap of the reward mentality. We’re talking about the state of mind that leads some people to burn 300 calories on a treadmill, feel they’ve earned a reward and then eat 500 calories worth of cheesecake. That’s bad math.
Understand that exercise is not about allowing you to reward yourself with junk food but about giving you the power to RESIST junk. You need to embrace the lifestyle rather than see it simply as a means to an end.
Exercise as Therapy
Margaret and I are not experts in how to deal with a traumatic past or stressful situations, but we do know one thing: food is not the answer. Neither are drugs or alcohol.
We have bad days, bad bosses, bad childhoods and thus bad cravings for eating junk. But it’s important that you don’t use the latter to medicate any of the former. The best healthy escape from a life that feels as if it’s sucking you dry is exercise, though a healthy sex life can help too.
If you’ve got some serious I-feel-messed-up-in-the-head issues, you may want to seek professional help and deal with these problems at their core. We wish you success and happiness; know that the information in this book can be used in conjunction with your therapy.
However, if you don’t believe psychological intervention is required, we offer an alternative: exercise therapy. It worked for me and it works for Margaret.
It’s worked for millions; people have created a positive relationship with exercise to give them something to feel good about. You too can wash the pain and stress away in a pool of sweat.
Exercise and Cognitive Capability
Actor Jesse Eisenberg’s character in the movie Zombieland extolled the virtues of “cardio” as an apocalyptic survival tool. I’ll bet it never crossed his mind that all that activity was making him a more scrumptious target for the walking dead.
All supposing a better-functioning brain is also a tastier one, that is.
I love The Simpsons and always laugh when Grandpa has a “senior moment.” But it’s not so funny to imagine it’s you getting senile. A little later in this chapter, we’ll get into how exercise pumps up your cognitive capabilities (and how this affects food intake), but first let’s examine how both resistance training (like weightlifting) and aerobic exercise can ward off a host of neurological impairments.
“It’s a medium-sized effect—but since we’re talking about the brain, medium is good,” Michelle Voss, assistant professor of psychology at the University of Iowa and lead author on a 2011 review of the effect of exercise on cognition, told me.
I’d say very good.
Voss and her team examined more than one hundred studies on the topic and discovered interesting things. Here’s one: the brain benefits of resistance training seem to differ from those you get from aerobic exercise.1 “Aerobic exercise improves ability to coordinate multiple things, long-term planning and your ability to stay on task for extended periods,” she said. Resistance training, which had been studied much less than the aerobic side of things, “improves your ability to focus amid distracters.”
This makes sense to me: aerobic exercise such as running involves staying on task for a long time, and if you’re training to get better, you need to stick to a plan. Weightlifting requires ignoring the spandex and lousy gym music and focusing enough to prevent the barbell from crushing your trachea during bench press.
The details of what’s going on inside your skull are fascinating. Voss explained that the fMRIs of people in their 60s showed increases in gray and white matter after just six months of exercise. This increase happens in the prefrontal lobes (which control decision making) and temporal lobes (which control sensory input), sites that typically diminish with age. With exercise, Voss told me, they grow.
Voss also explained that the hippocampus area of the brain, key for memory formation, shrinks 1 to 2 percent per year in those older than 60. But when people in this age group begin fitness regimens, it grows by 1 percent to 2 percent instead.
Beyond growing one’s brain, exercise improves the ability of different parts of the brain to work together, Voss says. It talks to itself better, but not in a multiple-personality kind of way.
Exactly how hard were the researchers pushing these over 60s? I could see how the excitement over the results might be curtailed if one had to become a power-lifting marathoner to reap benefits. But that’s not the case. Simple brisk walking for 45 minutes three times a week gets results.
And, Voss added, going much beyond that won’t give your brain much more: “There definitely is a law of diminishing returns. The difference between zero and moderate exercise is significant, whereas the difference between moderate and high exercise is much less so.”
Exercise also can help if you’ve got a genetically programmed Alzheimer’s time bomb ticking away in your noggin. In 2000, Dutch researchers published a study of 347 men, some of whom were genetically prone to Alzheimer’s due to a certain gene variant. Adjusting for a number of confounding factors such as smoking, drinking and education, the researchers found the inactive couch potatoes with the brain-wasting gene variant were four timesmore likely to develop Alzheimer’s than the fit people who carried the trait.2
Genetic tendencies aside, exercise reduces your risk of developing silent brain infarcts. And if you surmise that a “silent brain infarct” is something unpleasant, you’re right. It’s also called a “silent stroke.” It’s a lesion. On your brain. That’s bad.
In 2011, Columbia University researchers published a study of 1,238 elderly people in the journal Neurology, reporting that the 25 percent who were the most physically active were nearly half as likely to suffer these brain lesions compared with their inactive counterparts.3
Cerebellums and cerebrums and medullas, oh my!
As we learned back in chapter 3, scare tactics are lousy motivators for just about anything, including diet and physical activity, so let’s just forget all that doom and gloom stuff. (If you have the Alzheimer’s gene variant, forgetting should be easier … I know. I’m going to hell.) Since fear isn’t going to get your butt in gear, let’s get deeper into the benefits of how exercise both reduces stress and enhances brain function in myriad ways.
Chilling Out with Cardio
Do you ever feel like making a voodoo doll in the image of your boss, stabbing it full of pins, twisting its head off, then setting it on fire?
I remember those days.
Speaking of the old days, here’s to the good old mammoth-slaying Stone Age, when we really knew how to deal with stress. I’m talking about the fight-or-flight response, an inherited advantage coded into our genes via natural selection. Say you were chillin’ at the cave one day when in sauntered one of those saber-toothed murder beasts. The resulting stress would have elicited a massive surge of adrenal hormones; you’d jump to your feet and go all caveman on the intruder with valiant stabbing or cowardly fleeing.
Either way, the hormone surge was short-lived. Soon enough, you’d be roasting up tiger steaks or muttering about how you didn’t like that cave anyway as you headed off in search of a new abode to drag Daryl Hannah back to.
Fast-forward a few millennia, and it’s goodbye murder beast and hello performance reviews conducted by supervisors with double-digit IQs. And as good as it might be for stress relief, you can’t kidney-punch a domineering boss, throw him out a high-rise window and declare yourself alpha drone o’er the cube farm. Hooray for progress.
Instead, you send a snotty email to some unsuspecting IT guy about how your stupid keyboard isn’t Diet Coke–resistant, or yell at a slow driver from the safety of your minivan during the commute home. And when you finally get back home, you pour yourself a stiff drink and crab at the kids to stop doing those things that kids do before collapse in front of the TV to watch your favorite team lose or see The Bachelor give the boot to the one woman you thought deserved to win his heart.
Also, you eat. Remember all that stuff in chapter 1 about stress-induced eating? Stress does not lead to healthy food choices.
But it doesn’t have to be this way. Casually flipping through a 2006 copy of the Annals of the New York Academy of Sciences, I learned that exercise is the key to combating the stress of modern life.
The authors, from the University of Ioannina in Greece, first explain (in regard to the fight-or-flight response) that “stress responses can be elicited by emotional stimuli or professional and social stress.” No kidding. Just one negative memo handed down from on high can get the glucocorticoids and catecholamines flowing, but since you just sit there and stew, these adrenal hormones go unused. Your body stores them in visceral fat deposits, and this does bad things to you.4
The article then describes how these stored adrenal hormones disturb gonadal function (no wonder Viagra is such a big seller) as well as growth hormone and thyroid function. The authors explain how these “metabolic disturbances” lead to “comorbidities including central obesity, hypertension, dyslipidemia, and endothelial dysfunction.”5 In other words, unrelieved stress turns you into an artery-clogged hippopotamus with Limbaugh-like blood pressure and a lousy immune system. Oh, and it’s also hard on your brain.
The aforementioned cavemen didn’t have to worry about heart disease and senility. They became food for something else long before their arteries clogged up or their brains turned to tapioca. For real, this time: hooray for progress!
Continuing on in PhD-speak, the authors inform us that “accumulating evidence documents the beneficial effects of regular exercise in preventing or ameliorating the … comorbidities induced by chronic stress.”6
There’s that word “comorbidities” again—you want to avoid those.
The American Psychological Association has also weighed in on the subject of exercise and stress, noting online that “physically active people have lower rates of anxiety and depression than sedentary people.” This mood boost probably has nothing to do with that old myth about exercise unleashing a surge of happy-making endorphins, the statement adds, since there’s not much evidence for this popular belief.
Still, the effect may be more than just chemical. “Exercise seems to give the body a chance to practice dealing with stress,” according to the APA. “It forces the body’s physiological systems—all of which are involved in the stress response—to communicate much more closely than usual.”7
We can sum up all this science talk as follows: not only is stress killing you, it’s making you fat, which is also killing you. You can’t beat up your boss, but you can whale on a squash ball or pound the heck out of a pair of running shoes.
So try that instead, and stay employed.
Sweating Out the Sad
Maybe stress isn’t your big issue. Maybe you’re seriously bummed out instead, perhaps even clinically depressed. If so, you should know that a host of recent research affirms the anti-depressive effect of exercise.8 Depression overwhelms people. Even a mild case taxes your neurological capabilities, making wise food choices all the more challenging.
“We find the remission rate of depression in the highest exercise dose was right on par with the use of SSRIs [anti-depressant medication],” Dr. Tim Church, an expert in exercise and health at the Pennington Biomedical Research Center, told me. “This was about 200 minutes per week at a moderate intensity.”
What Church’s research is telling us is that just over three hours of exercise a week at moderate intensity is an equivalent treatment to anti-depressant medication. This doesn’t mean we should all flush our doctor-prescribed pills, but it does say a thing or two about the ability of physical activity to improve your mood.
Actor Mariel Hemingway says exercise saved her life.
“I suffered depression most of my life, and fitness and eating well has been very important in terms of battling this,” Hemingway told me. “My mother had cancer and my dad had heart disease and people were fighting all the time and there was a lot of alcohol. And being out and moving in nature is what made me feel complete and whole.” It’s worth noting that Mariel has lost seven family members to suicide. “It’s been very important in helping me get through those darker times,” she said.
“Exercise has a lot of benefit to the brain,” Dr. Church said. “With neural imaging looking at before and after exercise, we’re seeing changes in volume and size of the brain. It seems like reducing insulin has a positive effect on the brain.” Church explained that a molecule associated with improved brain health and repair is increased by exercise, and this molecule is also associated with lower levels of stress, anxiety and depression.
“People report exercise as being a good way to cope with stress,” Prof. Leigh Gibson told me. And he expands on Church’s comments on insulin: “There is literature developing that links insulin resistance [which can lead to type 2 diabetes] to poor appetite regulation.” Gibson explained that because exercise is powerful for controlling insulin sensitivity, it’s an additional mechanism for controlling what you eat.
“It can definitely regulate mood,” the professor and obesity researcher Carolyn Davis says of exercise. “It can make you feel better, more energized and can help you concentrate so you don’t need the distraction of nibbling on something.”
In Search of Happiness
Tomes abound on how to find it, but for many, happiness eludes. I believe it arrives via an indirect route. Physical activity elicits a physiological response that decreases stress, improves mood and battles depressive feelings. And from a psychological perspective, it’s hard not to smile when you’ve modeled your physique into something healthier that performs better, something you’re proud of. Make yourself proud.
Pumping Up the Cognitive Capabilities
In 2011, researchers from the University of South Carolina put 35 subjects on treadmills in order to figure out what exercise does for building mitochondria in the brain. If you remember middle-school biology, you’ll recall that mitochondria are the powerhouses of the cell because they provide most of its supply of chemical energy.
Granted, these “subjects” were mice, and that’s just as well, because the researchers then dissected the rodents’ brain tissue and examined the differences between treadmill-aficionado mice and cage-potato mice. Lo and behold, eight weeks of treadmill running made mouse brains more fatigue-resistant due to an increase in mitochondria.9 The little quadrupeds had pumped up their cognitive capabilities.
Michelle Voss explained that increased mitochondria increases the brain’s ability to get blood and oxygen where it needs to go. “There is a shorter refractory period as well.” Translation: you recover more quickly; periods of mental exhaustion are shortened.
This comes in handy. When I go for a long run, cycle or other workout session, it’s my brain that pushes me. I have to resist my legs, which are saying (or shouting), “Dude, we’re done.” My brain drives them by replying, “No, keep going.” When your body is screaming at you to stop, it takes an effort of will to override that. I believe this mental aspect of exercise is primary in continuing to push yourself even though you’re tired.
And yes, this mental toughness comes in handy for sticking to a healthy diet.
How Exercise Affects Eating Behavior
It’s time for this chapter to get climactic.
So far we’ve explained that exercise prevents brain rot, chills you out, creates feelings of happiness and makes your brain fatigue-resistant. All this contributes to becoming a better eater, yes. There is less stress to promote emotion-based eating, and you have the mental energy to choose your foods wisely.
Hang on, it’s about to get even more awesome.
“Physical activity and eating behavior are connected in the brain at the cognitive level,” Dr. Alonso-Alonso told me. “They share the same mental processes.”
I promised awesome, but awesome requires a bit of explanation, so bear with me.
Alonso-Alonso explained that we use goal-oriented systems in our brains to suppress impulses to eat junk food. Remember in chapter 2, when we talked about how higher impulsivity leads to higher body weight? In order to lose weight, we need to suppress that impulsivity. “The resources for goal-oriented eating behavior are greatly enhanced via physical activity,” he said. “Exercise improves eating behavior through brain and cognitive changes.”
Exercise enhances the brain’s “executive function,” which is what allows you to follow a plan. Sticking to a healthy diet means sticking to a plan. It’s about adherence to goals. You have to resist urges too, but mostly it’s about following a healthy eating plan.
So what is executive function? Dr. Alonso-Alonso explained that it’s located in the prefrontal cortex and is a combination of three things: your ability to control impulsive behavior (like the impulsive desire to reach for that doughnut), adaptability and working memory. These three things working in concert form your decision-making capabilities.
“There is a dose-response effect,” Alonso said. “A fitter person is going to have greater improvements in executive function and therefore better control of what they eat.”
Every time you eat, you’re making a decision, or decisions. Salad or hamburger? Takeout or home cooked? Not surprisingly, higher executive function = better decisions. Oh, and according to Brian Wansink, a professor of consumer behavior and nutritional sciences at Cornell University, we make over 200 decisions about food every day.10
Giving Senior Management a Support Team
Executive function is the senior management of your brain—and the folks in the corner office of your cerebral cortex have a tough job. Alonso-Alonso co-authored a 2011 paper in Obesity Reviews explaining that the modern environment—not just from a food perspective but from an everything perspective—tires out our executive controls on a daily basis.11 These controls are of a limited capacity, and the obesigenic environment means they are taxed. Eventually, the repeated need to control impulses becomes too much and we give in.
And by give in, I mean pig out.
That poor senior exec is overworked and, honestly, starting to suck at his job. He needs help. Enter exercise. Exercise is like giving the guy a venti Starbucks brewed by a barista who switched the caffeine dial to “weapons grade.” Except, unlike with coffee, you don’t get the crash. Or the spaziness. As mentioned earlier, being physically active chills you out. What I meant with the whole java analogy is that your poor, suffering decision-making capabilities get a significant boost from exercise. It’s like hiring a highly qualified assistant to keep that executive on task. Higher awareness and goal-oriented thinking is key to sticking to a diet. There really is a think-yourself-thin component to weight loss. But there is more to exercise than pumping up the cognitive capabilities. It also works on …
The Unconscious Level
Exercise makes you jones less. I wish the Joneses in my neighborhood would teach their stupid dog to shut up.
I digress. By less jones-ing I mean less craving, and not just food craving. Got a thing for the ganja and trying to cut back on your Visine usage? In 2011 researchers from Vanderbilt University in Nashville put a dozen potheads on treadmills and made them run for 30 minutes 10 times over a two-week period (I can just imagine the barfing-up of lung tissue that resulted). These were heavy users, and they saw a dramatic drop in both their cravings and their usage (a decrease of more than 50 percent) after just a few exercise sessions.12 Exercise was the only intervention. What’s especially interesting is that these people were deemed cannabis dependent, and didn’t even want treatment to help them stop smoking pot. But the exercise alone made them cut their marijuana use by more than half. Okay, maybe the coughing-up of alveoli while on the treadmill played a role, but note that the cravings were reduced as well.
And this goes way beyond the stinky green stuff. A 2011 analysis of the research published in Frontiers in Psychiatry revealed that exercise is a powerful tool for reducing self-administered use of a host of other mind-altering substances, including cocaine, meth, nicotine and alcohol.13
And this is why exercise is used in treatment for addictions.
“Patients work out with us every day,” Jennifer Dewey, fitness director for the Betty Ford Center in Rancho Mirage, California, told me. “It’s a mandatory part of the treatment program.” Betty Ford offers a wide variety of exercise opportunities, from outdoor activities such as hiking, biking, kayaking and rock climbing, to personal trainers and a yoga studio.
“It’s one of the critical components of sustaining sobriety,” Dewey said. And it’s not just while in treatment. “We give them routines they can take home and follow.” They help patients plan for a fitness-focused future as an aid to stay clean.
How does physical activity help people break bad habits? It’s because exercise is a replacement reward. It’s hitting the same neurochemical pathways in the brain as things like booze, drugs and even gambling. Back in chapter 3, we met Shinedown lead singer Brent Smith. He used exercise as his replacement reward to kick the booze habit. Coupled with cleaning up his diet, this led to tremendous weight loss for the rocker.
“Exercise can release opioids in the brain and be reinforcing,” Nicole Avena told me. “It’s hard for people to get to the point where it’s reinforcing, but after a while they crave it.” Yep. No one likes running the first several times they do it, but you’ve got to power through. Pretty soon you’ll look forward to your run in the same way you used to look forward to a bag of Doritos.
Speaking of which … exercise has the ability to reduce cravings for junk food as well.14
Help for the Reward Sensitive
Some people are reward sensitive. They are more likely to be addicted to food, alcohol, drugs and even gambling. I spoke with actor Daniel Baldwin, who has been on both Celebrity Rehab for his drug and alcohol addiction and on Celebrity Fit Club for being obese.
“I’d just turned 50, weighed 285, and my doctor had read me the riot act about my health,” Baldwin told me. He started intense training with a kettlebell, which led to dietary improvements, which led to losing 50 pounds in six months.
“My doctor didn’t recognize me,” he said. “He thought I was Billy Baldwin.”
Daniel says he loves working out with kettlebells because it’s fun and allowed him to lose fat and build muscle. He also says the confidence boost that comes with his new physique has been good for battling his addiction demons.
“What this does for me emotionally, psychologically and spiritually … has been very important in not relapsing,” he told me.
In other words, Daniel started getting his fix from working out. You can too.
Working Up a (Loss of) Appetite
Have you ever heard the expression “work up an appetite?” Yeah, that doesn’t actually happen. There are people out there who will tell you that the effort you put into exercise is wiped out by an enhanced appetite, therefore making physical activity useless for weight loss. Don’t listen to them; it’s just another form of snake oil. They’re telling you what you want to hear: Weight loss can come with no effort required. Buy my product.
Story time again.
Through an amazing case of serendipity, I had a mandatory work event at the same time as my wife’s cousin’s wedding on the other side of the country. She took the kids, and I had a few days of bachelorhood. I also had some nice weather, and one day I pushed myself further than I ever had on my bike, riding it for six hours solid. That evening was meant to be a gluttonous feast of beer, pizza and high-definition violence on my big-ass TV as loud as I damn well pleased.
Um. Not quite. I could barely stomach two beers, and I didn’t order the pizza. I made a salad and a salmon sandwich and could not finish them. I was just not hungry or craving beer, even though it was a rare night without husbandly or parental duties—plus I was getting to watch movies of bullets ripping through soft tissue, swords cleaving body parts and stuff getting blowed up. It was family-guy nirvana.
But that intense effort of a day on the bike resulted in an anorectic effect. This is not to be confused with anorexia, which is bad. What it means is that all that activity suppressed my appetite. I have noticed this effect many times after aerobic activity such as running, cycling and swimming, and it can last for much of the day. My six-hour ride is an extreme example; it doesn’t take nearly as much effort for the anorectic effect of exercise to kick in. A big pile of research supports the appetite-suppressing aspects of moderate physical activity.15
Interestingly, it seems to be mostly aerobic exercise that suppresses appetite, and not resistance training like weightlifting.16 As someone who is avid for both activities, I can attest to the veracity of this research. Uh, I mean, yeah. That seems about right. Research also shows that the more intense the exercise, the more profound the appetite- suppressing effect.17 That also seems right.
“Exercise is good to control appetite,” Avena said. “It releases hormones that are associated with satiety. You have a reduced desire to eat.”
Oh, and sitting around all day doing nothing doesn’t cause you to eat less.18 So much for that theory of “working up an appetite.” It’s ironic that burning extra calories has the power to make you ingest fewer calories, but there it is.
Regrowing the Dopamine Receptor Forest
Cast your mind back to chapter 2 for a moment and recall all the dopamine tsunami doom and gloom. The dopamine receptors are a forest that gets washed away with wave after wave of highly palatable tsunamis. And pretty soon you’re craving more and more of whatever your “highly palatable substance” is to get the same effect.
Evidence shows that exercise helps those receptors grow back.
A 1994 study published in Brain Research Bulletin determined that both synthesis and metabolism of dopamine have a close relationship with exercise. It makes these receptors more effective.19
And more recently, we have rats on meth. A 2012 study in Synapse let rats go on a meth bender, which must have been hilarious to watch, and it burned out their dopamine and serotonin receptors. After getting their chemical freak on, some of the rats were left to be cage potatoes, and others were made to run. The results show that the running rats significantly reduced the meth-induced brain damage, and that all the activity had a profound positive effect on their dopamine and serotonin receptors. And the lazy rats? Well, let’s just say it sucked to be them. The Swiss-cheesing brain effects of the dope lingered.20 Truthfully, it sucked for both groups. They all got their brains dissected.
Exercise can lead to a greater concentration of dopamine receptors (which are more sensitive). This, in turn, is tied to a reduced need for overconsumption of highly palatable food—your sensitivity to reward is higher, so it takes less of whatever it is you’re ingesting to make you feel good. When it comes to reward-seeking behavior, a little bit of junk food will go a long way.
Sweet, Sweaty Memories
All the positive benefits of exercise that we’ve discussed so far have been physiological, but there is also an important psychological link between exercise and what you eat.
What I mean is, if you begin making a big effort with exercise, do you want to undo it all by eating a bunch of crap? The answer for some people is yes, I earned it (we’ll deal with that at the end of this chapter). For many, however, exercise is the beginning of a subtle change in their relationship to food.
“When you exercise it creates a life perspective where you don’t want to undo it all with an unhealthy diet,” Eric Stice, the eating behaviorist, told me.
Knowing that you exercised makes you think more about consuming healthy foods that will feed your recovery. Knowing that you’re about to exercise makes you yearn for foods that improve performance. Seriously, I like doughnuts, but if I’m about to work out, a Boston cream is the last thing I want. And forget about during exercise. In the middle of my workout, a doughnut or other fatty, sugary treat could make me blow chunks. In my experience, an exercising stomach is finicky about what you put in it before a workout.
And there are studies that show exercise works as a gateway behavior (something that leads to adoption of a new behavior)—on the psychological level—for healthier eating.21 On an anecdotal level, the majority of the people I spoke to for this book about their weight loss journeys all attested that it was exercise that transformed the way they thought about food. Cheryl Berube is one example.
A 43-year-old graphic designer in Nova Scotia, Berube has had issues with emotional eating ever since she was a child. “I used to hate running and now I really love it,” she said. “I was always overweight as a child and never thought I would ever run.” But she did, and it changed her eating. “I think it reinforces better eating. I noticed when I do my normal exercises I don’t tend to snack in the evening, which is my worst problem.” The result? A whopping 160 pounds lost via simple diet and exercise, and she’s keeping it off.
Remember Jen McKinnon? She told me, “All this exercise has put me in the right mind-set for dealing with food. When my kids were driving me nuts I’d go for a run instead of going for the chocolate.”
“I fell into a big slump after university and I was eating crap all the time,” Jessica Banas, a 24-year-old office worker in Ontario, told me. “I gained about 40 pounds.” And, to toot my own horn, Jessica told me she read one of my articles about viewing food as fuel for exercise and started walking. Her knees didn’t like that, so she switched to cycling. “It was love almost right away,” she said. “It became my thing. I definitely consider what I eat before I cycle now. Being a dedicated cyclist means being careful about my diet.”
When it comes to eating, Dr. David Katz refers to exercise as “the wind beneath your wings.” Great, now I’ve got Bette Midler in my head. “It helps you want to care more about yourself and make better food choices,” he told me. “You want to put better fuel in the tank.”
Better fuel in the tank. Damn straight.
Sweet, Post-Sweaty Dreams
Have you heard that loss of sleep makes you fat? In 2012, researchers from St. Luke’s–Roosevelt Hospital and Columbia University presented to the American Academy of Sleep Medicine their fMRIs of 25 men and women showing that lack of sleep led to increased cravings for junk food.22
A number of other recent studies show a host of metabolic, hormonal and just plain old “too damn tired to exercise or eat properly” effects of insufficient sleep that lead to weight gain.23
And do you think there might be a few studies showing that exercise improves sleep? Yeah, there are; more than a few.24
How Exercise Improves Eating Behavior
There is a lot to digest (lame pun—gak!) about how exercise affects eating, so here’s a brief recap:
- Exercise reduces stress and helps alleviate depression, helping to control emotional eating.
- Exercise makes your brain fatigue-resistant, so it has the energy to think clearly about what you should eat. This is further enhanced by exercise improving quality of sleep.
- Exercise enhances the brain’s executive function, improving your ability to stick to a healthy eating plan.
- Exercise—especially if it’s intense—has an appetite-suppressing effect that can last for hours.
- On the psychological level, people who exercise regularly develop a keener interest in healthy eating to fuel their physical activities.
Three Dangerous Words
Don’t blow it.
No, those three aren’t the ones. But it’s important to know that lots of people do all this hard work with exercise, reap tremendous brain benefits, and then they blow it.
Dr. Yoni Freedhoff believes that it’s these three little words can cripple all your weight loss efforts: “Because I exercised.”
Yeah, this is part where I tell you about how a lot of people screw this whole exercise thing up.
“There is a lot of evidence showing overweight people doing a little exercise and then overeating to compensate because they rationalize that they have earned themselves a reward,” Eric Stice said.
Geez, a 2011 study of 94 people in Appetite found that just reading about exercise could cause people to eat more snacks.25
This is not the right way to think.
Here’s the scenario: you’ve done all this exercise, which creates all these tremendous brain benefits revealed throughout this chapter—benefits that give you the power to resist junk food—and yet you can override those incredible effects by being stupid.
The “because I exercised” mentality is stupid. It’s an illogical psychological breakdown for those looking to lose weight. If you feel that exercise isn’t giving you the power to resist junk food, you might be overdoing it. You could be pushing so hard that you’re causing a draining effect on your psyche. Instead of powering your brain to make wise food choices, you are—temporarily, at least—robbing yourself of the energy to eat properly. It works on the same logic as sleep deprivation causing poor eating choices because you’re too tired to make wise ones. So maybe you need to ease off on the physical activity. It’s yet another reason why we advocate a slow and steady adoption of exercise to give both your body and brain (and schedule) time to adapt.
The reward mentality—the bad math I mentioned where you think you’ve earned a 500-calorie piece of cheesecake after burning 300 calories on the treadmill—can be your downfall in all this. It’s common. It’s stupid, but it’s common. THIS IS YOUR WARNING!
Don’t do the reward mentality. Don’t fall for this trap.
If you need to reward yourself, do it with fitness clothes, GPS gadgets, new running shoes, a massage or spa treatment. You can even reward yourself with a roll in the hay—anything but calories.
“The bottom line is that weight loss is 90 percent about diet,” obesity researcher Dr. Sue Pedersen, a specialist in endocrinology and metabolism in Calgary, told me. “The studies show that exercise alone is not going to result in weight loss.”
There are rare exceptions of people losing weight with just exercise, but for the vast majority, you cannot out-exercise a bad diet. Again, think of exercise as your tool for better eating, not your excuse for lousy eating, because the calories burned via exercise can easily be undone (and then some) with one trip to the fast food drive-through.
Remember what Dr. Katz said: “You want to put better fuel in the tank.”
Better fuel in the tank. Better fuel in the tank. Better fuel, better fuel …
IMPORTANT NOTE: If I had to do it again, I’d write this chapter differently, because there is another alternative. A year after Lose it Right was published I wrote a piece titled “The Exercise Myth” that offers a viable alternative. Consider it a Chapter 4B to this book.
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