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Environmental Influences, Physical Activity, and Weight Status in 8- to 16-Year-Olds
Marsha Dowda, DrPH;
Barbara E. Ainsworth, PhD, MPH;
Cheryl L. Addy, PhD;
Ruth Saunders, PhD;
William Riner, PhD
Arch Pediatr Adolesc Med. 2001;155:711-717.
ABSTRACT
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Objective To assess the association between vigorous physical activity, participation
on sport teams and in exercise programs, television watching, family environment,
and weight status in youth.
Design Cross-sectional data from the Third National Health and Nutrition Examination
Survey.
Participants A group of 2791 youth between the ages of 8 and 16 years who were enrolled
in the Third National Health and Nutrition Examination Survey.
Main Outcome Measures Overweight was defined using age- and sex-specific 85th percentile of
body mass index using Center for Disease Control and Prevention growth charts.
Results Both males and females who had an overweight mother and or father were
more likely to be overweight compared with youth who did not have an overweight
parent. Females who watched 4 or more hours of television were more likely
to be overweight than those who watched less than 4 hours. Males and 14- to
16-year-old females who participated in sport team and exercise programs were
less likely to be overweight than their counterparts who did not participate.
Also, females with larger families and males from families with higher family
incomes were less likely to be overweight.
Conclusions These results suggest that family environment is associated with overweight
in youth and that sport and exercise program participants are less like to
be overweight and that, for females, increased television watching is related
to overweight.
INTRODUCTION
FROM 1976 to 1990, there was a 40% increase in the prevalence of overweight
among youth between ages 6 and 17 years.1, 2
Using a 95th percentile cutoff for body mass index (BMI), prevalence of overweight
had increased from 4% to 11%. Using an 85th percentile cutoff for BMI, it
is estimated that 22% of youth aged 6 to 17 years were overweight in 1995
and 25% in 1998.2, 3 Being overweight
during adolescence is associated with risk factors for cardiovascular disease,4 being an overweight adult,5
and increased risk of all-cause mortality, an increased prevalence of coronary
heart disease and other chronic diseases.6, 7
The increase of overweight and obesity among youth may be associated
with decreased physical activity. Traditional opportunities for physical activity,
such as required participation in school physical education at all levels,
have been reduced for many youth. The 1995 Youth Risk Behavior Survey (YRBS)
reported that 59.6% of surveyed students in grades 9 through 12 participated
in physical education classes, but only 48.8% participated in 1997.8, 9 The relationship of moderate to vigorous
exercise and weight status is open to interpretation. A body of work10, 11, 12 supports the traditional
view that physical activity is inversely associated with being overweight,
while other studies have failed to support the idea that participation in
physical activity is associated with a lower BMI.13, 14
Overweight has been associated with an increase in sedentary activities,
such as watching television. In the Third National Health and Nutrition Examination
Survey (NHANES III) children, interviewed between 1988 and 1994, who reported
watching 4 or more hours of television had on average greater BMI (P<.001) than children who reported watching less than 2 hours.15 Possible reasons for the association between television
watching and body fatness include the following: television may reduce time
spent in activities that require more energy expenditure,16
advertising may influence the selection of high-energy dietary food among
youth,17 and a positive relationship exits
between watching television and fat intake.18, 19
However, the association between watching television and obesity is also inconsistent
with some studies failing to find a relationship.10, 20
Because of the increased prevalence of overweight among youth and the
risk of subsequent chronic disease in adulthood, it is important to determine
the correlates of overweight in youth. Environmental factors that may be related
to overweight in youth include having overweight parents and other family
factors.21, 22, 23, 24
The purpose of this study was to determine what associations exist between
overweight in youth and vigorous physical activity, participation on sport
teams and in exercise programs, and time spent in a sedentary activity in
a triethnic sample of youth aged 8 to 16 years. Environmental factors, including
overweight status of mother and father, family size, and poverty index, were
also examined.
SUBJECTS AND METHODS
SUBJECTS
Study participants were enrolled in the Third National Health and Nutrition
Examination Survey (NHANES III). The NHANES was designed to describe the health
and nutritional status and estimate the prevalence of common chronic diseases
and associated risk factors of the noninstitutionalized civilian population
of the United States.25 Children 2 months to
5 years old, persons 60 years or older, non-Hispanic blacks, and Mexican Americans
are oversampled to ensure reliable estimates for those groups.
A group of 2791 children, 8 to 16 years of age, interviewed between
1988 to 1994, for whom data were complete, were included in the study. From
the original data set of 5052, youth were deleted who did not complete the
physical activity questions (n = 951). Other deletions included youth categorized
in the "other" race group (n = 184), those diagnosed as having physical conditions
that precluded physical activity or its measurement (n = 44), missing BMI
data for themselves or their biological parents (n = 917), missing poverty
index (n = 161), and time spent watching television (n = 4).
DEMOGRAPHIC AND FAMILY VARIABLES
The subject's age used in the study was that obtained during the physical
examination held in a mobile examination center.25
Children were divided into 3 age groups: 8 to 10, 11 to 13, and 14 to 16 years.
The race or ethnicity of the child was reported by an adult 18 years or older
during the home interview, and categorized as non-Hispanic white, non-Hispanic
black, and Mexican American. The respondent was the mother in 89% of the interviews
and the father in 7% of the interviews. Other respondents included older siblings,
grandparents, aunts, and uncles (4%). Family variables included family size
(number of family members living at home) and poverty index an indication
of socioeconomic status.25, 26
Poverty index was expressed as a ratio calculated by the US Census Bureau,
based on annual family income, family size, and other economic information.
Scores above 1.00 indicate that family income was above the poverty line.
BODY MEASUREMENTS AND WEIGHT STATUS
Physical measurements were performed during the physical examination.
Standing height, body weight, and skinfolds were measured using standard methods.25 Equipment was calibrated between each measurement.
Height and weight of the biologic parents were reported during the home interview.
Body mass index was calculated by dividing weight in kilograms by height
in meters squared. Youth were dichotomized into overweight and nonoverweight,
using age- and sex-specific 85th percentile of BMI from the Centers for Disease
Control and Prevention growth charts.27 Weight
status was used as the dependent variable in all analyses, with nonoverweight
the referent group. Biological parents were categorized as overweight if their
BMI was 25 or greater.28
PHYSICAL ACTIVITY AND TIME SPENT WATCHING TELEVISION
Physical activity behavior was assessed by asking how many times per
week the subjects "played or exercised enough to make them sweat and breathe
hard." Youth who reported 3 or more sessions of physical activity were classified
as active. Those reporting fewer than 3 sessions were in the low-active group.
A question was asked concerning the number of sport teams and exercise programs
participated in within the past year. Youth were instructed not to include
physical education or gym class. Those who reported no participation on sport
teams and in exercise programs were classified in the no-participation group,
and those who reported 1 or more sport teams and exercise programs were in
the participation group. Youth were also asked how many hours they had watched
television the day preceding the examination. Respondents were grouped into
4 or more hours or fewer than 4 hours watched per day.15
STATISTICAL ANALYSES
We used  2 analyses to determine differences, by sex,
in physical activity behaviors, television watching, and percentage overweight,
and t tests to determine differences in age, weight
indexes, family size, and poverty index between the weight groups. Crude odds
ratios (ORs) and 95% confidence intervals (CIs) were used to examine associations
between weight status of the youth and demographic characteristics, vigorous
physical activity, participation on sport teams and in exercise programs,
television watching, and the mother's and father's weight status. Multiple
logistic analysis models were calculated to examine the relationships of the
independent variables with weight status. Two-way interaction terms were tested
for age and race/ethnicity group by physical activity, sport teams and exercise
programs, hours of television watching, and weight status of mother and father.
Only interactions significant at P<.01 were considered
to minimize the possibility of a type I error. All analyses were conducted
separately for males and females.
The complex survey design that was used for NHANES III data collection
was incorporated into data analyses by using SUDAAN.29
Sampling weights were incorporated into all analyses. The sampling weights
had been calculated to take into account unequal selection probabilities resulting
from the cluster design and oversampling of some groups.
RESULTS
Demographic characteristics, physical activity behaviors, and television
watching are presented in Table 1.
Weighted percentages were not statistically different for sex, age groups,
or weight status between the subset (N = 2791) used in this study and those
with missing information (N = 2261). There were statistical differences (P<.05) for race/ethnicity, participation in vigorous
physical activity, sport teams and exercise programs, and watching television
for the subset, compared with those youth who did not meet the inclusion criteria.
About 51% of the study sample were male, 7.5% Mexican American, 14.2% non-Hispanic
black, and 78.3% non-Hispanic white, and were equally distributed among the
age groups. About 30% of the youth were overweight based on age- and sex-specific
85th percentile BMI from the Centers for Disease Control and Prevention growth
charts.27 Nearly 81% of the youth reported
vigorous physical activity 3 or more times per week and 24% watched 4 or more
hours of television, similar to the results reported by Andersen et al.15 About 65% of the youth participated on 1 or more
sport teams or in 1 or more exercise programs. There were no differences between
males and females regarding weight status, but more males reported participation
in 3 or more sessions of vigorous physical activity, participation on sport
teams and in exercise programs, and watching 4 or more hours of television
(Table 2).
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Table 1. Demographic Characteristics, Physical Activity Behaviors,
and Watching Television of Youth Aged 8 to 16 Years Who Did Not Meet (n =
2261) and Who Did Meet (n = 2791) Inclusion Criteria From the Third National
Health and Nutrition Examination Survey
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Table 2. Frequencies and Weighted Percentages for Physical Activity
Behaviors and Watching 4 or More Hours of Television and Overweight Among
1336 Males and 1455 Females Aged 8 to 16 Years in the Third National Health
and Nutrition Examination Survey
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The percentages of overweight youth were 7%, 39%, and 54%, with 0, 1,
or 2 overweight parents, respectively (Figure
1). Youth classified as overweight had significantly higher values
for BMI, the 3 skinfold measurements, and sum of skinfolds (P<.001) (Table 3). There
were no significant differences in mean age between the weight groups.
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Percentage of overweight youth (n = 2791) with 0, 1, or 2 overweight
parents.
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Table 3. Age and Weight Indexes by Overweight Status for 1336 Males
and 1455 Females Aged 8 to 16 Years in the Third National Health and Nutrition
Examination Survey
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Associations of categorical variables with overweight are shown in Table 4. Among females, non-Hispanic black
females were more likely to be overweight compared with non-Hispanic white
females. Male and female sport team and exercise program participants during
the past year were less likely to be in the overweight group. Females who
watched 4 or more hours of television were more likely to be overweight compared
with those who watched less. Females with an overweight father were more likely
to be overweight, as were those with an overweight mother for both males and
females. Family income (poverty index) was significantly higher among those
in the nonoverweight group compared with the overweight group for males and
females. No other significant associations were observed.
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Table 4. Weighted Percentage, Unadjusted Odds Ratios (ORs), and 95%
Confidence Intervals (CIs) for Categorical Variables nd Means and SEs for
Continuous Variables of Youth Aged 8 to 16 Years for Overweight Status, From
the Third National Health and Nutrition Examination Survey
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Table 5 shows the results
of multiple logistic analyses by sex. Non-Hispanic black males were less likely
to be in the overweight group when compared with non-Hispanic white males
(OR = 0.68). For males, participants on sport teams and in exercise programs
were less likely to be in the overweight group (OR = 0.63). Among the females,
a significant interaction was found between age group and sport team and exercise
program participation. Female sport team and exercise program participants
in the group aged 14 to 16 years were less likely to be in the overweight
group (OR = 0.23). Larger family size was associated with nonoverweight status
among females (OR = 0.88). Higher family income was associated with nonoverweight
for males (OR = 0.85). Females who watched 4 or more hours of television were
more likely to be in the overweight group than those who watched less television
(OR = 1.88). An overweight father increased the risk of being in the overweight
group (OR = 1.74 for males, OR = 1.81 for females) compared with those who
did not have an overweight father. Youth with an overweight mother were more
likely (OR = 2.31 for males, OR = 2.73 for females) to be in the overweight
group. No other significant associations were found.
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Table 5. Adjusted Odds Ratio (ORs) and 95% Confidence Intervals (CIs)
of the Independent Variables With Overweight Status for Males and Females,
From the Third National Health and Nutrition Examination Survey
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COMMENT
This study evaluated the environmental influences and physical activity
behaviors of overweight and nonoverweight 8- to 16-year-olds. Participation
in vigorous physical activity was not related to being overweight, while being
a sport team or exercise program participant was associated with not being
overweight among all males and 14- to 16-year-old females. Females who watched
4 or more hours of television on the day preceding the survey were more likely
to be overweight. Environmental factors associated with overweight were being
from smaller families for females, being from a family with a smaller family
income for males, and having at least 1 overweight parent for both.
In this study, 26% of youth who had participated on sport teams and
in exercise classes were overweight compared with 36% of youth who did not
participate. This association was significant for all males and for 14- to
16-year-old females. Ross et al30 reported
that most children's physical activity takes place in organized programs outside
of school. Sports participation is associated with better dietary habits,
with youth involved in organized sports reporting more fruit and vegetable
consumption than nonparticipants.31, 32
As part of dietary guidelines it is recommended that all Americans be
physically active each day.33 Among the suggested
activities for children and teens was joining after-school or community physical
activity programs. But data from the 1997 Youth Risk Behavior Survey indicate
that there is a decline in participation in both school and organized sports
unaffiliated with schools during high school, especially among females.9 This may be because of a decrease in accessibility
or availability of structured activity.
The association between parental weight status and children's BMI was
consistent with other studies. Youth with an overweight father or mother had
an increased risk of being overweight. Familial patterns of obesity have been
attributed to both genetics and family environment.1, 34
Youth in families with 1 or 2 overweight parents consume a higher percentage
of their energy intake as fat.18, 35
No doubt this contributes to the development of overweight in youth. The relationship
between overweight and other family variables is similar to previous findings.
Troiano and Flegal2 using NHANES III found
an inverse relationship between poverty index and non-Hispanic white males.
Increases in overweight in youth with smaller family size has been noted.24
Using NHANES III data, Andersen et al15
found a significant positive relationship between television watching and
BMI. This study, after controlling for demographic, physical activity behaviors,
and environmental variables, found that females who reported watching 4 or
more hours of television were more likely overweight than those who watched
fewer than 4 hours of television per day. Reducing television watching may
be a way to reduce and prevent overweight. Several recent school-based interventions
that were successful in reducing the amount of time spent watching television
reduced the BMI among females.36, 37
This study found that there is an association between overweight status
and lack of participation on sport teams and in exercise programs, but the
use of a cross-sectional study design precludes conclusions about temporal
sequence. Thus, it is not known if nonoverweight youth elected to participate
on sport teams and in exercise programs or if participation in these activities
helped to prevent youth from becoming overweight. It should also be noted
that the duration of vigorous physical activity was not assessed in NHANES
III and conclusions about a dose-response relation between the amount of physical
activity and overweight cannot be assessed. The subset used in this study
was composed of a slightly higher percentage of white youth; they were slightly
more active and watched fewer hours of television than those from the NHANES
III sample who were not included. Also, this study was limited to youth with
reported BMIs for both biologic parents. Despite these limitations, the inclusion
of data from a large national data set of youth with a wide range of ages
and 3 race/ethnic groups increases the external validity of these results.
School-based interventions have shown that physical education classes
can provide vigorous physical activity and promote skills necessary for developing
good activity patterns.38, 39, 40
Schools and communities need to provide physical activity programs that meet
the needs and interests of all youth.41 Physicians
can serve as advisors for schools and communities to ensure that such programs
are safe and enjoyable and provide activities for youth of all ages and race/ethnic
groups and for youth with different abilities and interests. Such programs
may help to prevent more youth from becoming overweight.42
Parents are instrumental in bringing about weight loss in youth. Epstein
and colleagues43, 44, 45, 46
presented a series of successful family-based interventions based on principles
of behavior modification in 5- to 12-year-old obese children that incorporated
physical activity, nutrition, and decreased television watching. Physicians
need to educate parents about the complications of overweight and evaluate
the diet and physical activity of their pediatric and adolescent overweight
patients.47 The physician should encourage
families to make changes that include increases in physical activity of the
overweight youth, limiting television watching, and development of healthy
eating habits.
CONCLUSIONS
No differences were observed in the number of sessions of reported vigorous
physical activity between overweight and nonoverweight youth. Overweight youth
were found to be less likely to have participated on sport teams and in exercise
programs and were more likely to have overweight parents. Normal-weight females
were more likely to have watched less television and come from larger families,
while males were from families with higher incomes than their overweight counterparts.
AUTHOR INFORMATION
Accepted for publication January 5, 2001.
From the Departments of Exercise Science
(Drs Dowda, Ainsworth, and Riner), Epidemiology and Biostatistics (Drs
Ainsworth and Addy), and Health Promotion and Education (Dr Saunders),
Norman J. Arnold School of Public Health, University of South Carolina,
Columbia, and the John Morrison White Clinic, University of South
Carolina, Lancaster (Dr Riner).
Corresponding author: Marsha Dowda, DrPH, Department of Exercise
Science, University of South Carolina, Columbia, SC 29208 (e-mail: mdowda{at}sph.sc.edu).
REFERENCES
| |
1. Rosenbaum M, Leibel RL. The physiology of body weight regulation: relevance to the etiology
of obesity in children. Pediatrics. 1998;101:525-539.
FREE FULL TEXT
2. Troiano RP, Flegal KM. Overweight children and adolescents: description, epidemiology, and
demographics. Pediatrics. 1998;101:497-504.
FREE FULL TEXT
3. Troiano RP, Flegal KM, Kuczmarski RJ, Campbell SM, Johnson CL. Overweight prevalence and trends for children and adolescents: the
National Health and Nutrition Examination Surveys, 1963 to 1991. Arch Pediatr Adolesc Med. 1995;149:1085-1091.
ABSTRACT
4. Freedman DS, Dietz WH, Srinivasan SR, Berenson GS. The relationship of overweight to cardiovascular risk factors among
children and adolescents: the Bogalusa Heart Study. Pedatrics. 1999;103:1175-1182.
5. Guo SS, Roche AF, Chumlea WC, Gardner JD, Siervogel RM. The predictive value of childhood body mass index values for overweight
at age 35 y. Am J Clin Nutr. 1994;59:810-819.
FREE FULL TEXT
6. Must A, Jacques PF, Dallal GE, Bajema CJ, Dietz WH. Long-term morbidity and mortality of overweight adolescents: a follow-up
of the Harvard Growth Study of 1922 to 1935. N Engl J Med. 1992;327:1350-1355.
ABSTRACT
7. Must A, Spadano J, Coakley EH, Field AE, Colditz G, Dietz WH. The disease burden associated with overweight and obesity. JAMA. 1999;282:1523-1529.
FREE FULL TEXT
8. Kann L, Warren CW, Harris WA, et al. Youth Risk Behavior Surveillance—United States, 1995. Mor Mortal Wkly Rep CDC Surveill Summ. 1996;45:1-84.
9. Kann L, Kinchen SA, William BI, et al. Youth Risk Behavior Surveillance—United States, 1997. Morb Mortal Wkly Rep CDC Surveill Summ. 1998;47:1-89.
10. Wolf AM, Gortmaker SL, Cheung L, Gray HM, Herzog DB, Colditz GA. Activity, inactivity, and obesity: racial, ethnic, and age differences
among schoolgirls. Am J Public Health. 1993;83:1625-1627.
FREE FULL TEXT
11. Ward DS, Trost SG, Felton G, et al. Physical activity and physical fitness in African-American girls with
and without obesity. Obes Res. 1997;5:572-577.
ISI
| PUBMED
12. Hernández B, Gortmaker SL, Colditz GA, Peterson KE, Laird NM, Parra-Cabrera S. Association of obesity with physical activity, television programs
and other forms of video viewing among children in Mexico City. Int J Obes Relat Metab Disord. 1999;23:845-854.
FULL TEXT
|
ISI
| PUBMED
13. Huttunen NP, Knip M, Paavilainen T. Physical activity and fitness in obese children. Int J Obes. 1986;10:519-525.
ISI
| PUBMED
14. Romanella NE, Wakat DK, Loyd BH, Kelley LE. Physical activity and attitudes in lean and obese children and their
mothers. Int J Obes. 1991;15:407-414.
ISI
| PUBMED
15. Andersen RE, Crespo CJ, Bartlett SJ, Cheskin LJ, Pratt M. Relationship of physical activity and television watching with body
weight and level of fatness among children: results from the Third National
Health and Nutrition Examination Survey. JAMA. 1998;279:938-942.
FREE FULL TEXT
16. Dietz WH, Gortmaker SL. Do we fatten our children at the television set? obesity and television
viewing in children and adolescents. Pediatrics. 1985;75:807-812.
FREE FULL TEXT
17. Taras HL, Sallis JF, Patterson TL, Nader PR, Nelson JA. Television's influence on children's diet and physical activity. J Dev Behav Pediatr. 1989;10:176-180.
ISI
| PUBMED
18. Robinson TN, Killen JD. Ethnic and gender differences in the relationships between television
viewing and obesity, physical activity, and dietary fat intake. J Health Educ. 1995;26(suppl):S91-S98.
19. Jeffrey DB, McLellarn RW, Fox DT. The development of children's eating habits: the role of television
commercials. Health Educ Q. 1982;9:174-189.
ISI
| PUBMED
20. Robinson TN, Hammer LD, Killen JD, et al. Does television viewing increase obesity and reduce physical activity?
cross-sectional and longitudinal analysis among adolescent girls. Pediatrics. 1993;91:273-280.
FREE FULL TEXT
21. Maffeis C, Talamini G, Tato L. Influence of diet, physical activity and parent's obesity on children's
adiposity: a four-year longitudinal study. Int J Obes Relat Metab Disord. 1998;22:758-764.
FULL TEXT
|
ISI
| PUBMED
22. Eck LH, Klesges RC, Hanson CL, Slawson D. Children at familial risk for obesity: an examination of dietary intake,
physical activity and weight status. Int J Obes Relat Metab Disord. 1992;16:71-78.
ISI
| PUBMED
23. Fogelholm M, Nuutinen O, Pasanen M, Myöhänen E, Säätelä T. Parent-child relationship of physical activity patterns and obesity. Int J Obes Relat Metab Disord. 1999;23:1262-1268.
FULL TEXT
|
ISI
| PUBMED
24. Dietz WH. Childhood obesity: susceptibility, cause, and management. J Pediatr. 1983;103:676-686.
FULL TEXT
|
ISI
| PUBMED
25. Department of Health and Human Services, Public Health Services, Centers
for Disease Control and Prevention. NHANES III Reference Manuals and Reports [book
on CD-ROM]. Hyattsville, Md: National Center for Health Statistics; 1996.
26. Crespo CJ, Ainsworth BE, Keteyian SJ, Heath GW, Smit E. Prevalence of physical inactivity and its relation to social class
in U.S. adults: results from the Third National Health and Nutrition Examination
Survey, 1988-1994. Med Sci Sports Exerc. 1999;31:1821-1827.
ISI
| PUBMED
27. Centers for Disease Control and Prevention/National Center for Health
Statistics. CDC Growth Charts: United States. Hyattsville, Md: Dept of Health and Human Services; 2000.
28. Executive summary of the clinical guidelines on the identification,
evaluation, and treatment of overweight and obesity in adults. Arch Intern Med. 1998;158:1855-1867.
FREE FULL TEXT
29. Shah BV, Barnwell BG, Bieler GS. SUDAAN User's Manual, Release 7.5. Research Triangle Park, NC: Research Triangle Institute; 1997.
30. Ross JG, Dotson CO, Gilbert GG, Katz SJ. After physical education-physical activity outside of school physical
education programs. J Phys Educ Recreation Dance. 1985;56:35-39.
31. Pate RR, Trost SG, Levin S, Dowda M. Sports participation and health-related behaviors among U.S. youth. Arch Pediatr Adolesc Med. 2000;154:904-911.
FREE FULL TEXT
32. Baumert PW, Henderson JM, Thompson NJ. Health risk behaviors of adolescent participants in organized sports. J Adolesc Health. 1998;22:460-465.
FULL TEXT
|
ISI
| PUBMED
33. Nutrition and Your Health: Dietary Guidelines for Americans. 5th ed. Hyattsville, Md: Dept of Agriculture and Dept of Health and
Human Services; 2000. Home and Garden Bulletin 232.
34. Birch LL, Fisher JO. Development of eating behaviors among children and adolescents. Pediatrics. 1998;101:539-549.
FREE FULL TEXT
35. Nguyen VT, Larson DE, Johnson RK, Goran MI. Fat intake and adiposity in children of lean and obese parents. Am J Clin Nutr. 1996;63:507-513.
FREE FULL TEXT
36. Gortmaker SL, Peterson K, Wiecha J, et al. Reducing obesity via a school-based interdisciplinary intervention
among youth: Planet Health. Arch Pediatr Adolesc Med. 1999;153:409-418.
FREE FULL TEXT
37. Robinson TN. Reducing children's television viewing to prevent obesity: a randomized
controlled trial. JAMA. 1999;282:1561-1567.
FREE FULL TEXT
38. Sallis JF, McKenzie TL, Alcaraz JE, Kolody B, Faucette N, Hovell MF. Effects of a 2-year physical education program (SPARK) on physical
activity and fitness in elementary school students. Am J Public Health. 1997;87:1328-1334.
FREE FULL TEXT
39. Luepker RV, Perry CL, McKinlay SM, et al for the CATCH Collaborative Group. Outcomes of field trial to improve children's dietary patterns and
physical activity: the Child and Adolescent Trial for Cardiovascular Health. JAMA. 1996;275:768-776.
ABSTRACT
40. Perry CL, Stone EJ, Parcel GS, et al. School-based cardiovascular health promotion: the Child and Adolescent
Trial for Cardiovascular Health (CATCH). J Sch Health. 1990;60:406-413.
ISI
| PUBMED
41. Guidelines for school and community programs to promote lifelong physical
activity among young people: Centers for Disease Control and Prevention. MMWR Morb Mortal Wkly Rep. 1997;46:1-36.
PUBMED
42. Goran MI, Reynolds KD, Lindquist CH. Role of physical activity in the prevention of obesity in children. Int J Obes Relat Metab Disord. 1999;23(suppl 3):S18-S33.
43. Epstein LH, McCurley J, Wing RR, Valoski A. A five year follow-up of family-based behavioral treatments for childhood
obesity. J Consult Clin Psychol. 1990;58:661-664.
FULL TEXT
|
ISI
| PUBMED
44. Epstein LH, Valoski A, Wing RR, McCurley J. Ten-year follow-up of behavioral, family-based treatment for obese
children. JAMA. 1990;264:2519-2523.
ABSTRACT
45. Epstein LH, Valoski A, Wing RR, McCurley J. Ten-year follow-up of behavioral family-based treatment for childhood
obesity. Health Psychol. 1994;13:373-383.
FULL TEXT
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