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Mythbusters: Exercise Is Key for Weight Loss
June 13, 2017
The Myth
Exercise is huge for weight loss.
The Reality
Believe it or not, exercise for weight loss is not one of the top benefits of exercise. Regular exercise comes with a ton of health benefits, but if you’re trying to lose weight, your best bet is to focus on your diet.
The Nitty Gritty
If you’ve ever struggled with long-term weight loss or getting rid of those last few pounds, you’ve probably wondered which is more important: revamping your diet or hitting the gym regularly. The verdict is in: When your goal is weight loss, changing your diet is what makes all the difference.
Reason 1: You don’t burn that many calories through physical activity.
While all the advertisements for gyms and campaigns to get people moving might lead you to believe otherwise, the truth is that for most people physical activity accounts for only about 30 percent of the calories the body burns a day. (1) The other 70 percent is determined by your basal metabolic rate or the energy your body expends just by living.
In fact, one study found that measuring physical activity alone is not a key determinant of unhealthy weight gain in children. In other words, kids who are quite physically active can still be overweight, likely because of food choices. (2)
We can look at this another way, too. The prevailing theory is that a person needs to cut about 3,500 calories to lose one pound (note that the exact calories vary depending on the starting weight of the person and other individual factors). (3) You can do this by eating 3,500 fewer calories or working them off.
That means if you wanted to lose one pound a week, you would have to cut out about 500 calories a day — the equivalent of four slices of bacon, one can of soda and a bagel with cream cheese or just 4.5 ounces of cheddar cheese. (4)
If you wanted to burn that same amount of calories via exercise, you’re looking at roughly a five-mile run every day of the week. Which are you more likely to stick to?
Reason 2: You’re overestimate how many calories you burn …
You know that terrific feeling after a workout, when you allow yourself a slice of pizza or an extra slice of cheese at lunch because you had such a kick-butt workout? You’re not alone. Most of us actually overestimate how intense a workout is. (5) The result is that you might sabotage your own exercise efforts by overcompensating how much food you need afterward.
A study conducted by the Department of Pediatrics at Harbor-UCLA Medical Center had both males and females who regularly exercise track what they ate and how much energy they spent. On paper, the subjects lost weight. In reality, however, they underestimated how much they were eating and overestimating how many calories they burned. (6)
Reason 3: … And underestimate how much you eat.
No matter how stringent you are with your exercise routine, bodies adapt. What was once a tough workout for you might be a lot easier a few months later, affecting how many calories it burns.
And unless you spend every waking hour at the gym, you cannot outrun the 27-plus meals you eat a week (and that’s before snacks!). In yet another study, this one conducted by the School of Human Kinetics at the University of Ottawa and published in the Journal of Sports Medicine and Physical Fitness, participants were asked to exercise and estimate how many calories they burned on a treadmill. (7) They were then taken to a buffet and asked to eat the equivalent of the calories burned — and ate two to three times the amount that they burned.
The Fix: Don’t Exercise for Weight Loss — Eat for Weight Loss, Exercise for All the Other Benefits
Please note that I’m not advocating avoiding exercising. The benefits of exercise are widely reported and range from feeling happier to reducing your risk for a range of ailments, from heart disease to cancer. An exercise plan that suits your physical levels is so important.
But if you’re trying to lose weight, adjusting your diet is your best bet as opposed to exercise for weight loss. What are some easy ways to create new healthy eating habits?
1. Make Your Own Meals
This is a biggie. Being able to know exactly what’s in your food and how it’s prepared, along with weighing out portion sizes, is critical.
If you’re struggling with having enough time to cook, I suggest spending an hour or two on the weekend prepping your food and snacks for the week. I’d go so far as to suggest that you skip a gym session and use that time to get your food ready instead. It’s that key.
If you need suggestions, I have a variety of healthy recipes to choose from, ranging from breakfast to mains and even good-for-you sweet treats.
2. Practice Mindful Eating
Keeping a food journal to keep track of how much you’re eating, noticing when you emotionally eat and fully being in tune at meal time are all great ways to start making gradual changes to your diet that you can stick to.
3. Make Sustainable Swaps
Healthy eating shouldn’t go out the window once you reach a desired weight. It might take longer, but making smaller, gradual changes that you can stick to for good is the way to go. For a diet that’s full of delicious foods and leaves you satisfied — and promotes optimal health — I suggest the healing foods diet.
4. Exercise Smarter, Not Harder
Instead of spending hours at the gym at low intensity, try high-intensity interval training. HIIT workouts burn more calories in less time. Weight lifting and strength training also help you increase the afterburn effect, or how many calories you’ll burn post-exercise. When you combine these with a sound, nutritious diet, you’re sure to see results.