Dr. Catrine Tudor-Locke, Ph.D.

The Obesity Epidemic Why It is Happening?

We’re in the midst of a worldwide obesity epidemic. Research tells us that here in the U.S., 55% of the adult population is either overweight or obese.

But you don’t have to take researchers’ word for it; go to any place where a lot people gather (like a mall or movie theater) and you’ll see that there seems to be a high proportion of overweight people. If more body fat just meant buying larger clothing sizes, it wouldn’t be such a problem. But overweight and obesity are well known to be associated with premature death, and many chronic diseases including heart and vascular diseases, diabetes, postmenopausal breast cancer and osteoarthritis. Ill health is only part of the price we pay. The economic costs totaled 70 billion dollars in 1995 in the U.S. And I won’t begin to go into the social and psychological costs of overweight and obesity.

So, why are we in the middle of an obesity epidemic when we live in a society that values being thin? What has changed in the past few decades that has had such a negative impact on the health of so many people? There are likely many contributing social and environmental factors, but it all comes down to a postive energy imbalance, that is, energy-in-exceeding energy-out. Basically, if you take in more (eat more) than you expend, you gain weight. So the recipe for an obesity epidemic would seem to be eating too much (and/or making poor choices including high fat foods) and not exercising.

So what is really going on? I suspect that this obesity epidemic is due to eating too much and /or making inappropriate choices relative to a diminishing energy-out side of the equation. This latter factor bears closer scrutiny. Although partipation in intentional leisure-time physical activities has remained stable, incidental activities, or opportunities to be naturally active on a daily basis, have dwindled down the last four decades. What do I mean by naturally active? Being natually active goes beyond exercising for its own sake – it includes energy expended throughout the day in incidental work activities, chores, childcare, errands, commuting, etc.

I believe that walking (regardless of form or purpose) has been especially susceptible to the ravages of modernization. I also believe that the loss of background activity necessary for daily living (or natural activity) is a major contributor to the obesity epidemic – making eating even modest amounts and infrequent high fat delicacies too much to handle without creeping weight gain.

On a more positive note, the benefits of increased physical activity are well documented, and include weight loss and maintenance, reduced risk of chronic disease, and improved quality of life. In short, physical activity is good for you. But most people who are practiced in the art of sedentary daily living find that adopting and maintaining a structured and regimented exercise program is exceedingly difficult to do. How many times have you started an exercise program? And don’t feel guilty about your answer – you’re not alone. One often-cited finding is that about 50% of aerobic class joiners drop out in the first 3-6 months, mot in the first 12 weeks. In fact, it is so difficult to keep up with an exercise routine that a whole branch of research has sprung up to study exercise adoption and adherence behavior!

If you think that signing up for an aerobics class or committing to training for a marathon are the only ways to reap the benefits of a physically active lifestyle, think again. Walking, regardless of form or purpose, qualified as an appropriate physical activity. In 1996 the U.S. Surgeon General endorsed a public health recommendation to accumulate 30 minutes or more of moderate intensity activity (like brisk walking) on most, if not all, days of the week.

What I propose is a more practical and palatable approach to naturally increasing and systematically tracking daily physical activity – especially walking. The approach I recommend is amenable to individual preferences, abilities amd schedules. It does not require a great deal of planning or expense. Importantly, it does not dismiss the concept of intenional exercise, just built it in as one of the many optional strategies for increasing daily physical activity.

It’s time to take back our naturally active lives. I’m not suggesting we go back to banging our laundry on rocks. Really, I’m quite delighted to be living in this day and age. But given the situation, we need to consider becoming more aware of opportunities for natural activity that exist in our lives, tracking our daily activity, and making choices about our personal levels of activity on a day-to-day basis. Sound complicated? It doesn’t have to be. Let me introduce you to the simple and inexpensive pedometer.

The Promise of Pedometers

The idea of using some sort of instrument to count the number of times you step during a day is nothing new. Leonardo DaVinci considered such an instrument in his quest for a distance-measuring device to construct maps both for military purposes and canal construction.

Compared with modern times, Leonardo lived in a time characterized by more opportunities to be naturally active – there was no need to track physical activity in his era. But times and circumstances have changed and modern incarnations of the pedometer have evolved to address a new need. Earlier mechanical versions were not dependably accurate and researchers discounted them for the most part. Today a number of commercially available electronic pedometers are considered accurate and reliable. And researchers are slowly beginning to accept their potential for measuring physical activity, specifically ambulatory activity, or walking behavior.

The Next Step

I wear a pedometer every day (I believe in practicing what I preach).

I want to emphasize that using a pedometer to increase and monitor physical activity does not dismiss the concept of exercise, that is, intentional activity for its own sake. Once you are able to sustain 9,000-13,000 steps/day week after week and you are ready for further improvements, I recommend bumping up the intensity and/or trying new activites for variety. Walk a little faster sometimes – consider jogging – play sports that require a little more exertion, etc.

I also recommend some form of resistance training (e.g., weight lifting) in addition to pedometer self-monitoring. The number of steps/day you take are related to energy expenditure and general cardiovascular fitness – but resistance training provides the independent benefits of strength and shape – so the combined approach is best for maximing health benefits.

Source:
Manpo-kei The Art of Step Counting How to be naturally active and lose weight! By Catrine Tudor-Locke, Ph.D.

Catrine Tudor-Locke, Ph.D.
Associate Professor
Exercise and Wellness
Arizona State University
She walks or bikes to work regularly, tries to keep true to a weight training regimen, walks to local coffee and lunch spots for a break from her sedentary academic occupation, and runs and walks regularly in her neighborhood with friends. She averages 14,000 steps/day.