Seeing ourselves through the obesity epidemic

Prologue: A hopeful view of the future. In 2010 the incidence of obesity has been slowed. Local politicians,

school officials, employers and other community leaders, with local, state and federal funding, matched by

industry dollars, have collaborated to change policy and implement programs in support of health

communities. New communities and community improvement projects are planned to support physical

activity. Parks and Recreation programs are fully funded. Worksites have wellness centers, employees are

given the opportunity to use them, and employers are reimbursed by health insurance carriers to promote a

healthy workplace. Community physical activity promotions for all ages occur throughout the year. In

schools, physical education classes are held in all grades from 3 to 5 days a week for 45 minutes each day,

with an emphasis on building life-long skills, providing a liberal dose of moderate to vigorous activity, and

providing all children throughout their school years the opportunity to experience the joy of physical activity

and learn its relation to good health and well-being. Schools are opening their doors to offer exercise facilities

and health promotion activities during off-school hours for the surrounding community. Daycare facilities for

the elderly are staffed with health promotion professionals, and physical activity programs, health

promotions, cafeteria health plans, and health credits are all in place to improve quality of life. Fast foods are

no longer available at schools or in the worksite. Vending machines

dispense healthy choices and cafeterias have salad bars, fresh fruit,

nutritious soups, skim and low-fat milk and yogurt, and bottled water,

along with a balanced menu of complex carbohydrates, healthy protein

sources, and foods low in saturated fat. Food is no longer used as a

reward in schools. Physical activity events have become the major

school fund-raising projects. Community agencies have added physical

activity programs before and after school for both adult and child

enrichment, and the science of exercise and nutrition are infused

throughout the school curriculum. Federal, professional and private

organizations such as The President’s Council for Physical Fitness and

Sports, The Cooper Institute, and AAHPERD have joined together to

promote physical activity and health-related physical fitness, offering

awards to all children who are active and fit, regardless of their athletic

prowess. Schools and worksites are also recognized for their innovative

programs for healthy eating and physical activity. Their efforts receive

national exposure so others may learn from their success. Consequently,

model programs developed in response to the Surgeon General’s Call

for Action1 such as the Mayor’s Healthy City Initiative in Tucson,

Arizona, the state-wide Obesity Prevention Programs in Arkansas and

Colorado, and the Federal Hearts and Park program have spread

throughout the country. The obesity epidemic is slowed and prevalence

in adults and children has decreased to the pre-1980s prevalence.

Series 5, No. 3 Sept 2004

Published quarterly by the

President’s Council on

Physical Fitness and Sports

Washington, D.C.

★

Guest Authors:

T.G. Lohman1, Ph.D., S.B. Going1,2,

Ph.D., and L. Metcalfe1, M.S.

University of Arizona, Center for

Physical Activity and Nutrition, 

Departments of Physiology1 and

Nutritional Sciences2

★

Co-edited by:

Drs. Charles B. Corbin and

Robert P. Pangrazi,

Arizona State University, and

Dr. Deborah Young, 

University of Maryland

President’s Council on Physical Fitness and Sports

ResearchDi est
Ongoing evaluation efforts have also been

improved. Children and adults’ levels of physical

activity and fitness, body composition and eating

habits are followed every five years through a

national probability sample survey by NCHS and

CDC, and well-being indexes are offered on a

community, state, and national level to provide

guidance and support for individual, family,

school, and worksite improvements in health

behavior. 

In contrast to this, the U.S. currently has the

highest prevalence of obesity in the world. Adult

obesity has increased steadily over the past 20

years.2 Currently 30.4% of the U.S. population is

obese (BMI >30).3 Another 34.7% is overweight

(BMI between 25 and 30). The prevalence of

obesity ranges from 25 to 51% depending on

gender, age, and racial/ethnic group with higher

levels in Mexican American, African-American

and Native American populations. Recent

estimates of prevalence have shown obesity has

increased 50% or more over the past decade in

every state,4 with direct annual health costs

estimated at $90 billion.5

Recent childhood surveys show obesity has

increased at all ages throughout the 1990s to reach

levels higher than at any time in our nation’s past.

Today, 16% of children 6 through 19 years (1999-

2002) are overweight (95th percentile of sexspecific BMI-for-age growth charts), and another

31% are at risk for overweight (85th percentile of

sex-specific BMI-for-age growth charts).3

Historically, federal surveys have followed the

secular changes in height, weight and skinfolds. In

the 1990s an indirect body composition measure

was added (bioelectrical impedance in NHANES

III) and more recently (NHANES IV) a more

direct measure of body fatness and fat distribution

(DXA estimated fatness). Hopefully, soon we will

be able to define childhood and adult obesity in

terms of fatness rather than weight for height and

thus have a more health-related measure of body

composition to follow.

Standards have been developed for children. Using

data from the Bogalusa Heart Study, Williams et

2

al.6 and Lohman7 showed that body fatness of 25%

for boys and 32% for girls was associated with an

increase in cardiovascular risk factors in children 8

to 18 years of age independent of age and race.

These health-related body composition standards

have been used in the national Fitnessgram

(Cooper Institute) for the past ten years. BMIs and

skinfolds corresponding to 25% fat for boys and

32% for girls have been identified, and are also

used in schools throughout the country to

encourage health-related fitness.

We know that heavier children are at greater risk

for diabetes and for higher levels of fasting glucose

and insulin related to body fatness, physical

inactivity and low fitness levels. We also know that

exercise programs, if vigorous enough, can lower

chronic disease risk factors and support healthy

body weight and composition at any age. Research

has shown that childhood obesity tracks into

adolescence, and adolescent obesity is predictive

of adult obesity. Thus, early intervention is

important.

Much of the increase in obesity in the past 20

years has been associated with environmental

rather than genetic factors. Leading candidates

include less physical activity and lower caloric

expenditure, more time in sedentary pursuits (TV,

Internet and video games), less walking to school

and in neighborhoods, larger portion sizes, greater

consumption of refined carbohydrates, and lack of

active time in schools and at the worksite. The

International Obesity Task Force8 has addressed

the prevalent causes of obesity in a comprehensive

report. The report identifies underlying social

changes in developing countries that have likely

contributed to rising levels of obesity throughout

the world, including increased motorized transport,

increased traffic hazards discouraging pedestrians

and cyclists, fewer opportunities for recreational

physical activity, increased sedentary recreation,

multiple TV channels around the clock,

availability of greater quantities and variety of

energy-dense foods, increased promotion and

marketing of these foods, more frequent and

widespread food purchasing opportunities, more

use of restaurants and fast food stores, larger
3

portions and promotion of better “value” for

money, increased frequency of eating occasions,

and rising use of soft drinks to replace water,

especially in schools.8 The decline in real food

prices, increase in caloric intake from quick-toprepare foods, urban sprawl, fewer transportation

choices, more eating out at restaurants, especially

fast food restaurants, scarce leisure time for

women, and high cigarette prices and taxes

causing more smokers to quit are other likely

contributors.9 Clearly, the problem is complex and

widespread interventions on many levels are

drastically needed.

Two major venues for obesity intervention are

schools and families. Schools have the advantage

of reaching many children with a given

intervention. Several school-based interventions

have been conducted or are under way:

PATHWAYS, CATCH, SPARK, MSPAN, GEMS,

TAAG, and STOPP T2D. Although some of these

programs have increased physical activity and

improved healthy eating, none has decreased

obesity (TAAG and STOPP T2D are still in process).

In most school-based studies, families have played

only a peripheral role in the intervention. We know

from other research10, 11 that weight loss

interventions are most successful when parents and

their children together are targeted to lose weight,

although some success in both children and adults

is possible when only parents are targeted for

weight loss. Less success occurs when only

children are involved in the intervention. The best

long-term success (5 and 10 years after

intervention) reported by Epstein et al.10 occurred

when both parents and children lost weight. Thus,

it may be that for school-based interventions to be

effective, we must find creative ways to involve

parents in obesity prevention approaches.

There is growing sentiment that nurture rather than

nature is driving the obesity epidemic.12

Urbanization, mechanization, and the associated

cultural and environmental changes have lowered

daily energy expenditure. Past generations

endeavored to build a society in which the amount

of hard physical labor was reduced and there

would be an opportunity to enjoy leisure pursuits.

They succeeded, although not without unintended

and unexpected consequences. The results of a

recent survey suggest present-day Americans have

over 33 leisure hours per week.13 While better

technology has increased production, technology

and productivity have created a faster and more

stressful pace of life, with time pressures for all of

us.14 Despite what appears to be significant

opportunity for leisure pursuits, Americans

perceive they have far less (on average about 15

hrs.) leisure time. When they do seek relaxation,

people of all ages tend to choose sedentary

activities such as watching television, surfing the

web, and playing video games more than physical

activity. According to the most recent BRFSS

Survey, greater than 70% of U.S. adults do not

achieve the recommended levels of moderate and

vigorous physical activity that have been

associated with important health outcomes, and

more than 30% of adults report no leisure time

physical activity. These numbers have been

remarkably stable over recent decades. Research

also suggests physical activity levels are low in

children and youth. Based on the 1999 Youth Risk

Behavior Survey,15 only 45% of U.S. youth, aged

14-18 years, participate in moderate physical

activity (MPA) for 30 minutes on more than two

days per week, and only 65% reported

participating in vigorous physical activity for 20

minutes on three or more days per week. 

While direct evidence for a link between physical

activity and obesity is lacking, the ecological

evidence is impressive. Sedentary jobs have

increasingly replaced jobs with significant physical

demands. The number of cars and time spent in

cars has increased. Physical education, a child’s

main opportunity for physical activity during the

school day, has been drastically reduced in many

schools. Observational studies have shown

physical activity is significantly correlated with

weight and body fat. Individuals who have

successfully lost weight report participating in

significant amounts of daily physical activity,16 and

physical activity is the best predictor of weight

maintenance after weight loss. The available

longitudinal data also suggests physical activity is
4

vital to maintaining healthy weight.17 In the

Aerobics Center Longitudinal study cohort,

improvements in fitness (assessed by treadmill

time) over 2 years time were associated with

attenuated weight gain over an average of 7.5

years. Considered in toto, the available evidence

suggests an active lifestyle should be promoted

early and maintained throughout adulthood to

prevent substantial weight gain and reduce obesity

with advancing age.

The optimal dose of physical activity is

controversial and undoubtedly depends on the

desired outcome. Prevention of weight gain,

weight loss, and weight maintenance after loss

likely requires different levels of energy

expenditure. Current recommendations, released

jointly by the CDC and ACSM in 1995,18 and later

endorsed by the U.S. Surgeon General,19 The

National Institutes of Health,20 and the American

Heart Association,21 promote “30 minutes or more

of moderate intensity physical activity on most,

preferably all, days of the week,” which equates to

about 150 minutes of moderate intensity exercise

or approximately 1,000 kcals/week of energy

expenditure. Based mostly on epidemiologic data

that showed a consistent association between

physical activity and disease risk and outcomes,

the CDC/ACSM recommendation was aimed at

the 40-50 million U.S. adults who are sedentary

and who account for much of the public health

burden of chronic disease. Weight loss/weight

maintenance was not the primary consideration,

and whether the CDC/ACSM recommendation

represents the optimal dose for maintenance of a

healthy weight at different ages is unclear.

More recently, the IOM Committee on Dietary

Reference Intakes released its report, which

included a recommendation for 60 minutes of

daily moderate intensity physical activity.22 The

IOM report suggested that “30 minutes per day of

regular activity is insufficient to maintain body

weight in adults in the recommended body index

range of 18.5 up to 25 kg/m2 and [to] achieve all

the identified health benefits fully.” Hence, to

prevent weight gain as well as to accrue additional,

weight-independent health benefits, the IOM panel

recommended approximately twice the minutes of

moderate physical activity that was recommended

by CDC/ACSM.23

In practice, the discrepancies among activity

recommendations are easy to reconcile. Sedentary,

overweight individuals will benefit from

increasing their daily physical activity, even if they

do not lose a significant amount of weight, and

700-1,000 kcals/week is a reasonable initial goal.

Once regular activity is adopted and fitness

improves, further increases in weekly minutes of

moderate intensity and/or vigorous activity can be

undertaken to reach a level of activity/energy

expenditure that prevents weight gain or regain.

The major challenge facing the U.S. today is how

to increase physical activity for the population.

There are many possible approaches and as with

obesity treatment it is quite likely that “one size

does not fit all.” As with weight loss, there is

substantial physical activity recidivism. Perri and

others have suggested that obesity should be

treated with a chronic disease model to improve

overall success; thus, maintaining some contact

with participants is necessary for long-term

success.24 A similar approach may be necessary to

sustain lifetime physical activity.

Recently, the non-federal Task Force on

Community Preventive Services reviewed the

literature on physical activity interventions

published between 1980-2000.25 Eleven types of

interventions described in reports emphasizing

effectiveness studies were broadly categorized into

informational approaches, behavioral and social

approaches, and environmental approaches.

Following the Community Guide rules of

evidence,26 two informational interventions

(“point-of-decision” prompts to encourage stair

use and community-wide education) three

behavioral and social interventions (school-based

PE, social support in community settings, and in

individually adopted health behavior change) and

one environmental and policy intervention

(creation of enhanced access to places for physical

activity, combined with informational outreach)

were recommended for translation and

dissemination. These interventions were judged
effective at increasing physical activity (either

proportion of active individuals, frequency of

engagement, or active minutes) or

cardiorespiratory fitness. Results show it is

possible to develop interventions that increase

activity and fitness and we believe it is vital that

translation and dissemination proceed,27 even

while research continues to refine and develop new

interventions. Five types of interventions were not

recommended (classroom-based health education,

behavioral and social support in family settings,

mass media campaigns, college-aged physical and

health education, classroom-based health

education focused on reducing television viewing),

because of insufficient studies, lack of a consistent

effect on physical activity or fitness, or lack of a

link to physical activity. This lack of

recommendation does not mean that studies in

these areas are not worthwhile but simply that

sufficient evidence is not yet available to support a

recommendation. 

A key concept for obesity treatment that is likely

to be important for maintenance of desirable

physical activity is the approach of continuous care

or continuous contact. It is essential to develop and

test low-cost strategies, with broad reach, for

delivering and sustaining proven interventions.

The current lack of information on strategies for

long-term maintenance of healthy behaviors that

support weight loss represents a major challenge,

and long-term studies are greatly needed.28 As with

smoking cessation, adoption and maintenance of

recommended levels of physical activity and longterm healthy eating patterns will likely require

sustained efforts reinforced on multiple levels

(individual, family, community) and in multiple

venues (physician visit, school and workplace,

community, etc.). Interventions that are tailored to

the specific circumstances and needs of the

individual are likely to be more successful over the

long term, particularly if they are designed to

adapt to changing situations and needs. Lifestyle

activity may be another effective strategy for

increasing physical activity, increasing fitness, and

modifying body weight in overweight adults. 

How can we encourage more people to find the joy

in physical activity and movement? Adopting an

active lifestyle is more likely to occur when

individuals clearly perceive the personal and social

benefits. In general, we need to provide education

and skill development, opportunities to build selfefficacy and encourage modeling of physical

activity and healthy eating by peers, teachers,

parents and co-workers. The incorporation of

functional strength training into existing exercise

programs to enhance coordination, strength and

endurance in everyday activities is also helpful.

This “functional” approach to strength training

allows individuals to perform their daily activities

and recreational pursuits with greater ease and less

injury. Goal setting, completing personal contracts,

and keeping exercise logs are other strategies for

guidance and accountability. Individuals also need

to develop coping skills to deal with an

increasingly inactive and sedentary society. Coping

skills can be defined as ways to problem solve

daily challenges that interfere with your best

exercise and healthful eating intentions. Some

examples would be to schedule physical activity

for the week taking into consideration options for

morning, work day, and evening activity.

Exercising with a partner may improve

maintenance because of accountability to another

person. Identifying the key benefits and barriers to

regular physical activity may also assist in

developing a personal plan. If exercise makes you

feel better, gives you more energy, clears your

head so you can think better, provides social

interaction opportunities, allows you the calorie

deficit to enjoy a rich dessert, and makes you feel

more alive in your body, these insights are

invaluable to your decision making process as your

day unfolds and the opportunities to make healthy

choices become more enticing. Regular evaluation

of progress is motivational. Widespread and

increasing access to computers and the Internet

supports access to downloadable physiological,

activity and dietary measurement tools, with the

potential for real-time feedback. Personal coaches

can, in person or using the Internet, address fitness

and nutritional concerns, and also offer support for

stress reduction, time management, and other

important health and wellness areas. 

5
osteoporosis prevention, diabetes prevention and

cancer prevention. Communities will also work

with environmental engineers to develop

sidewalks, bicycle and walking trails and parks to

make it easier for people to be more physically

active.

Epilogue. The year 2010 is but 6 years away.

Clearly, the challenge is great and there is much

work to do. Marshalling changes into sustainable,

effective programs that integrate physical activity

and healthy eating into daily life aimed at longterm changes in weight-related behaviors reaching

into all parts of the community with political and

community participation is one way of seeing

ourselves through the pandemics of obesity,

sedentary lifestyle and poor nutrition. It will take

great leadership at all levels to accomplish such an

ambitious goal of transforming the social and

environmental forces that influence eating and

physical activity behaviors at the population level.

Effective individual approaches must be coupled

with community programs and state and federal

policy initiatives, along with research

demonstrating social and environmental changes,

with due concern for economically disadvantaged

and at-risk populations. To quote Dr. David

Satcher, our previous U.S. Surgeon General

(2001), “This approach should focus on health

rather than appearance, and empower both

individuals and communities to address barriers,

reduce stigmatization and move forward in

addressing overweight and obesity in a positive

and proactive fashion”.8

6

Primary care doctors should play a pivotal role in

addressing sedentary lifestyles and the resulting

obesity epidemic. To assist time-pressed primary

care doctors to address fitness in their practice,

fitness professionals can provide training to

physicians to learn to assess body mass index and

waist measurement and determine a patient’s

physical activity level, counsel overweight patients

on the potential health risks they face and on

reducing their daily calorie intake, write an

exercise prescription, encourage using a pedometer

with a long-term goal of walking 10,000 steps a

day, and recommend strength training exercises for

specific needs.5

Available research suggests that preventative

lifestyle programs by healthcare providers and

companies cost far less than treating lifestyle

diseases. Obese individuals are at increased risk

for physical ailments such as type 2 diabetes,

hypertension, stroke and coronary heart disease,

and cancer. The easiest and most cost-effective

resources a company can provide are websites

where employees can access important wellness

information, including risk factor assessment tools,

fitness calculators, guidelines for beginning a

fitness program, guidelines for healthy eating, and

how to contact certified fitness and nutrition

professionals. These programs should “follow”

employees using the Internet, instant messaging,

and other tools to promote adherence and longterm success. Many states and cities will provide

funding for community health promotion programs

including walking programs, weight management,
7

Please Post

President’s Council on Physical Fitness & Sports

200 Independence Avenue, S.W., Washington, DC 20201

(202) 690-9000 • FAX (202) 690-5211

Much of the increase in obesity

in the past 20 years has been associated

with environmental rather than

genetic factors. Leading candidates include

less physical activity and lower caloric

expenditure, more time in sedentary

pursuits (TV, Internet and video games),

less walking to school and

in neighborhoods, larger portion sizes,

greater consumption of

refined carbohydrates, and

lack of active time in schools and

at the worksite.

T.G. Lohman, Ph.D., S.B. Going, Ph.D.,

and L. Metcalfe, M.S.

University of Arizona, Center for Physical Activity and

Nutrition, Departments of Physiology and Nutritional Sciences
8

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