The Truth About Exercise and Your Weight
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out how fitness really factors in.
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If you've been working out
and eating fewer calories but your extra pounds won't budge, you may be
wondering why that seemingly simple strategy isn't working.
The truth is you may need a
reality check about what to expect from exercise.
1. Exercise is only part
of the weight loss story.
There's no getting around
your tab of calories in and calories out.
The obese patients Robert
Kushner, MD, clinical director of the Northwestern Comprehensive Center on
Obesity, treats often tell him they're not seeing the results they want from
exercise.
"They will say, 'I
have been working out three days a week for 30 minutes for the past three
months, and I have lost 2 pounds. There's something wrong with my
metabolism,'" he says.
Kushner tells patients that
exercise is very good for them, but for weight loss, he emphasizes starting
with a healthy diet. "First, we've got to get a handle on your diet,"
Kushner says. "As you're losing weight and feel better and get lighter on
your feet, we shift more and more toward being more physically active. Then
living a physically active lifestyle for the rest of your life is going to be
important for keeping your weight off."
Other experts have had
success including physical activity early on. But they stress that the amount
of exercise is key.
James O. Hill, PhD,
director of the Center for Human Nutrition at the University of Colorado at
Denver, says it's easier to cut 1,000 calories from a bloated diet than to burn
off 1,000 calories through exercise. "But there are many, many studies
that show that exercise is associated with weight loss when done in enough
volume and consistently," he says. "It depends how much you do."
For Pamela Peeke,
spokeswoman for the American College of Sports Medicine's "Exercise is
Medicine" campaign, fitness is a crucial part of a weight loss program,
but it's for reasons that go beyond calorie burning. She praises its mind-body
benefits, which will help with motivation over the long haul.
Peeke asks her patients to
start walking as a way to "celebrate" their bodies with activity.
"For years, they've blown off their body," Peeke says. "By them
actually using their bodies, they can begin to integrate them back into their
lives and not use them as a source of torture or torment or shame."
2. Exercise is a must for
weight maintenance.
"I come back to this
over and over and over," Hill says. "You can't find very many people
maintaining a healthy weight who aren't regular exercisers. What we find is
that people who focus on diet aren't very successful in the long run without
also focusing on physical activity."
Hill warns that people can
be "wildly successful temporarily" at losing weight through diet
alone. But there's plenty of data that show that those people regain the weight
if they aren't physically active.
Timothy Church, MD,
director of preventive medicine research at the Pennington Biomedical Research
Center in Baton Rouge, La. says, "When it comes to weight, you can't talk
about diet alone, and you can't talk about exercise alone. You absolutely have
to address both issues at the same time."
3.
Food splurges may undo your efforts.
Exercise may not buy you as
much calorie wiggle room as you think.
"The average person
overestimates the amount of activity they're doing by about 30% and
underestimates their food intake by about 30%," says Kathianne Sellers
Williams, a registered dietitian and personal trainer.
"When' I'm looking at
people's food and activity logs, sometimes things just don't add up," she
says. "People think, 'Oh, I just did 60 minutes at the gym' or 'I just did
30 minutes at the gym' and think that counteracts a lot of what they're eating.
But the reality is our food portions are huge."
Plus, Peeke says, you have
to look at all the other calories you ate or drank that day and how sedentary
you were apart from your workout.
"The rest of the day,
you're sitting down and you're also eating other things," Peeke says.
"How are you going to burn that stuff, let alone this extra little treat
that you just thought you wanted?"
It's hard to accurately estimate
how many calories you burn working out, Church says. "If it is a hard
workout," he says, "you kind of intuitively think, 'Wow! That's cool!
I just put enough in the bank for two days!' and you really haven't."
4. Exercise machines may
not tell the whole calorie story.
Treadmills and other
exercise gear often have monitors that estimate how many calories you're
burning.
Kong Chen, director of the
metabolic research core at the National Institutes of Health, says those
displays are "close, but for each individual they can vary quite a
bit."
Chen suggests using calorie
displays on exercise equipment for motivation but not as a guideline to how
much you can eat.
"It doesn't matter if
the display says 300 or 400 calories. If you do that every day or increase from
that level, then you've achieved your purpose. But I wouldn’t recommend feeding
yourself against that," Chen says.
Those machines don't
account for the calories you would have burned anyway without exercising.
"It isn't 220 calories
for those 40 minutes of exercise versus zero," Kushner says. "If you
were sitting at work or playing with your kids, you’re probably burning 70
calories during that period of time. You have to subtract what you would burn
if you didn't exercise. So the overall calorie burn becomes much less."
5. One daily workout may
not be enough.
Your best bet for your
weight -- and for your overall health -- is to lead a physically active
lifestyle that goes above and beyond a brief bout of exercise.
"It's not just about
30 minutes of exercise," Chen says. "It's about fighting the
sedentary environment."
"The message isn't
that the 30 minutes on the treadmill isn't good," Hill says. "It's
that the 30 minutes on the treadmill isn't going to make up for 23-and-a-half
sedentary hours." Hill encourages people to weave activity throughout
their day. "Do something to move and make it fun," he says.
Chen also recommends
setting realistic expectations and taking "small steps all the time"
toward your weight goal.
As much as calories-in vs
calories-out matters, don't forget about stress, sleep, and other factors that
can affect your weight, Williams says. "We need to look at someone's total
lifestyle, not just whether someone hits the gym," she says. "Weight
and obesity are really multifactorial, and it really simplifies it just to
break it down to nutrition and exercise. Those are really big pieces but
definitely not the only pieces."
