Dietary and Physical Activity Behaviors of Middle School Youth

By Zapata, Lauren B Bryant, Carol A; McDermott, Robert J; Hefelfinger, Jennie A

ABSTRACT BACKGROUND: Obesity has become a national epidemic among youth. Declining physical activity and poor nutrition contribute to this epidemic. The purpose of this study was to obtain data on middle school students’ physical activity and nutrition knowledge and practices.

METHODS: The Youth Physical Activity and Nutrition Survey was developed and distributed to a probability sample of Florida public middle schools (n = 73) in spring 2003, producing data from 4452 students in grades 6-8.

RESULTS: Results showed that less than one fourth of youth met expert recommendations for daily fruit and vegetable intake and less than one fifth identified the daily fruit and vegetable serving recommendation. Less than half of students reported eating breakfast daily. More non-Hispanic black youth reported not engaging in vigorous or moderate physical activity during the previous 7 days, and more girls and Hispanic youth reported not attending any physical education classes during the average school week.

CONCLUSION: These findings demonstrate that dietary and physical activity behaviors and knowledge among these middle school youth are setting the stage for the obesity epidemic to continue.

Keywords: nutrition and diet; child and adolescent health; policy; risk behaviors; physical fitness and sport.

Obesity among youth is a serious problem confronting families, communities, health care providers, and public health authorities. Over the past 3 decades, the prevalence of obesity has more than tripled for youth aged 6-11 years and more than doubled for youth aged 12-19 years.1 Based on data from the 2003-2004 National Health and Nutrition Examination Survey, 18.8% of 6- to 11-year-old youth and 17.4% of 12- to 19-year-old youth were overweight (body mass index [BMI] greater than or equal to the 95th percentile for age and gender). Moreover, 37.2% of 6-to 11-year-old youth and 34.3% of 12- to 19-year-old youth were at risk for overweight (BMI at or above the 85th percentile but less than the 95th percentile for age and gender).2

Jain3 estimated that between 40% and 70% of obese children will become obese adults. This precursor condition for adult obesity is a critical public health threat because of the associations with several chronic diseases including hypertension, type 2 diabetes, coronary heart disease, stroke, osteoarthritis, and sleep apnea.1 Obesity also has been associated with premature mortality.1,4,5

Many of the behaviors that lead to obesity are established during childhood. Consequently, increasing the proportion of children meeting dietary and physical activity guidelines has been identified as a key strategy in the primary prevention of obesity.1 In addition, current recommendations for physical activity for children and adolescents include engaging in at least 60 minutes of physical activity on most (preferably all) days of the week.6

Furthermore, several Healthy People 2010(7) objectives have been developed to monitor the nation’s progress over time related to youth dietary and physical activity behaviors as a cornerstone of obesity prevention. These objectives include the following:

19-5: Increase the proportion of persons aged 2 years and older who consume at least two daily servings of fruit.

19-6: Increase the proportion of persons aged 2 years and older who consume at least three daily serving of vegetables, with at least one-third being dark green or orange vegetables.

22-6: Increase the proportion of adolescents who engage in moderate physical activity for at least 30 minutes on 5 or more of the previous 7 days.

22-7: Increase the proportion of adolescents who engage in vigorous physical activity that promotes cardiorespiratory fitness 3 or more days per week for 20 or more minutes per occasion.

22-9: Increase the proportion of adolescents who participate in daily school physical education.

Although the Youth Risk Behavior Surveillance System (YRBSS) of the Centers for Disease Control and Prevention is implemented in alternate years to assess the prevalence of health risk behaviors among youth, including dietary and physical activity behaviors, these data are only collected among high school students. Considerably less data on the prevalence of dietary and physical activity behaviors are available for middle school youth.

As part of its surveillance function, the Florida Department of Health developed the Youth Physical Activity and Nutrition Survey (YPANS) for monitoring middle school students’ knowledge and practices related to physical activity and nutrition. This article summarizes findings from the 2003 YPANS to disseminate new knowledge on the prevalence of dietary and physical activity behaviors among middle school youth and to guide future interventions and policy changes to combat the escalating childhood obesity problem.

METHODS

Sampling

All regular public middle schools in Florida containing grades 6, 7, or 8 defined the accessible population. The population was implicitly stratified by region and sampled systematically with probability proportional to enrollment in grades 6-8. Within the 73 participating middle schools, either all classes meeting during a particular period of the day or all classes in a subject required by every student were included in the sampling frame to minimize selection bias. Systematic equal probability sampling was used to select classes from each participating school. All students in selected classes were included in the sample.

Transmittal forms tracked the total number of students eligible for surveying as well as the number of surveys completed. School personnel administered the YPANS survey during spring 2003 simultaneously with the Florida Youth Substance Abuse Survey and the Florida Youth Tobacco Survey. The 3 surveys were collated and randomly distributed within classrooms, with the intent of every third student completing the YPANS survey. To derive the overall response rate for the YPANS survey, the number of eligible YPANS students was divided by the number of completed surveys, where the number of eligible YPANS students was equal to one third of the total number of eligible students. The overall response rate for the YPANS survey was 71.8%. The 2-stage cluster sample design resulted in a state representative sample of 4452 middle school students in grades 6-8 from 73 schools.

Instrument Development and Administration

Content for the YPANS was developed by experts in nutrition, physical activity, health promotion, and epidemiology. The survey consisted of 92 items, with questions on demographic characteristics, body weight, dietary behaviors, restaurant and school dining, school vending machine use, knowledge about nutrition and physical activity, participation in physical activity behaviors, after-school activities, television viewing, computer and video game use, and other items related to health behavior and status; all of which were self-reported by youth. Many items were taken directly from the YRBSS, which has been shown to be a reliable instrument.8 Content validity of the YPANS survey was established by an expert review panel, and readability of the instrument was deemed appropriate using the Flesch Reading Ease Formula9 (score of 78.5) and the Flesch-Kincaid Grade Level Formula10 (grade level of 5.6, with 5% use of passive voice).

Parental consent forms were sent home with students at least 3 days in advance of the survey date. In most cases, passive consent (the parent returns the form only if the student cannot participate in the survey) rather than active consent (the parent must return the form for the student to participate) was required by school districts.

Each survey administrator was given a script to read to students assuring them that participation in the survey was anonymous and voluntary and that no penalty would be imposed on students selecting not to participate or lacking parental permission. In addition, students were told that they could skip any question that they were not comfortable answering; however, rates of missing data for behavioral items were minimal (<5%). Students were also told that results would be reported collectively and not by class or school. These measures protected student privacy and promoted their comfort in answering the questions honestly.

Construct Measurement

Dietary Behaviors. Several survey items were combined to assess how many fruits and vegetables youth were consuming, on average. The first 4 items were borrowed from the YRBSS: (1) During the past 7 days, how many times did you drink 100% fruit juices such as orange juice, apple juice or grape juice? (Do not count punch, Kool-Aid, sport drinks, or other fruit-flavored drinks); (2) During the past 7 days, how many times did you eat fruit? (Do not count fruit juice); (3) During the past 7 days how many times did you eat green salad? and (4) During the past 7 days how many times did you eat vegetables? (Vegetables include foods like broccoli, spinach, carrots, squash, tomatoes or green beans). Using these items, a score was created through a 2-step process. First, a sum was calculated of the number of times during the previous 7 days youth reported each behavior. Second, an estimate was made of the average number of servings per day over the past 7-day period. This variable was created using the same methods as the comparable construct on the YRBSS. Milk consumption was assessed by the following items: (1) During the past 7 days, how many glasses of milk did you drink? (Include milk you drank in a glass or cup, from a carton or with cereal. A milkshake counts as a glass of milk. Count the half pint of milk served at school as equal to one glass) and (2) When you drink milk, what kind of milk do you usually drink? Soda consumption was measured by the item: During the past 7 days, how many sodas did you drink? Daily consumption of breakfast was assessed by the item: During the past 7 days, how many mornings did you eat breakfast? Note that the first milk consumption item was adapted from the YRBSS and that YPANS researchers developed the remaining items.

Physical Activity. Youth physical activity was assessed by 3 items worded identically to ones from the YRBSS: (1) On how many of the past 7 days did you exercise or participate in physical activity for at least 20 minutes that made you sweat and breathe hard, such as basketball, soccer, running, swimming laps, fast bicycling, fast dancing, or similar aerobic activities? (2) On how many of the past 7 days did you exercise or participate in physical activity for at least 30 minutes that did not make you sweat and breathe hard, such as fast walking, slow bicycling, skating, pushing a lawn mower, or mopping floors? and (3) In an average week when you are in school, on how many days do you go to physical education (PE) classes? YPANS researchers developed an additional closed-ended item: When you get home in the afternoon, what do you spend most of your time doing?

Nutrition and Physical Activity Knowledge. YPANS researchers developed 2 items to measure nutrition and physical activity knowledge: (1) How many fruits and vegetables do you think experts recommend you should eat in a day? and (2) How much physical activity do you think experts recommend that kids your age should get?

Data Analysis

Data were weighted by sex, grade, and region to provide estimates generalizable to all public school students in grades 6-8 in the 7 regions of Florida. Weighted frequency distributions were computed to describe the distribution of response options for each item. Bivariate analyses (specifically, chi-square tests of independence) were conducted to test for significant associations between demographic characteristics of youth (sex, grade level, and ethnicity) and selected survey items. The criterion for statistical significance was set at .05 to reduce the likelihood of committing a type II error. Point estimates and 95% confidence intervals around the estimates were calculated for each behavioral item in which a bivariate association with respondent demographics was explored. When chi-square results revealed a statistically significant bivariate association, 95% confidence intervals around point estimates were examined to identify subgroups that had nonoverlapping intervals indicating statistically significant differences. All survey data were analyzed using the SUDAAN Software for Statistical Analysis of Correlated Data 8.0.2 (Research Triangle Institute, Research Triangle Park, NC) to account for the 2-stage cluster sample (students selected within classrooms within schools).

RESULTS

Demographics

The majority of respondents were between 12 and 14 years of age, and the sample was about evenly distributed with respect to sex and grade level. The sample was representative of the Florida public school population by race and ethnicity. Almost half (46.2%) of the respondents identified themselves as non-Hispanic white; 24.6% as non-Hispanic black; 21.4% as Hispanic or Latino; and 7.8% as American Indian, Asian, Native Hawaiian or other Pacific Islander, or some combination of ethnicities (excluding youth who self- identified as white and Hispanic or black/African American and Hispanic). This last category is referred to subsequently in this article as "other/multiethnic" when used in reporting analyses. Finally, respondents reported earning mostly As or Bs in school (63.4%). The data in Table 1 summarize the demographic characteristics of respondents.

Dietary Behaviors

Consumption of Fruits and Vegetables. Slightly less than one fourth (22.8%) of respondents reported consuming 5 or more fruits and vegetables per day. No sex differences were found; however, significant differences by grade level (chi^sup 2^ = 23.3, df = 2, p < .0001) and ethnicity (chi^sup 2^ = 17.3, df = 3, p < .005) were identified. Examination of 95% confidence intervals revealed that more sixth-grade middle school peers (26.6%) consumed 5 or more fruits and vegetables per day than their seventh-grade (23.9%) and eighth-grade (18.6%) middle school peers. In addition, more non- Hispanic black youth (25.9%) and other/multi-ethnic youth (29.2%) consumed 5 or more fruits and vegetables per day during the previous 7 days than non-Hispanic white youth (20.0%). Table 2 provides the point estimates and 95% confidence intervals for fruit and vegetable consumption by sex, grade level, and ethnicity.

Milk Consumption. Just more than one fifth (21.9%) of survey respondents reported that they drank 3 or more glasses of milk per day during the past 7 days. There were statistically significant differences for sex (chi^sup 2^ = 101.5, df = 1, p <.0001) and ethnicity (chi^sup 2^ = 25.1, df = 3, p < .0001). More boys (27.5%) than girls (16.0%) drank 3 or more glasses of milk per day during the previous 7 days. Fewer non-Hispanic black youth (15.8%) drank 3 or more glasses of milk per day during the previous 7 days compared to non-Hispanic white youth (24.9%) and Hispanic youth (22.5%). When asked what kind of milk they usually drank (respondents could select more than 1 response), the most common answers were whole milk (40.0%), chocolate milk (34.0%), and 2% milk (25.8%). About 1 (9.2%) of 10 respondents did not know what kind of milk they drank.

Soda Consumption. Approximately one fourth (26.0%) of middle school students drank 2 or more sodas per day during the previous 7 days. There were no statistically significant differences for sex, grade level, or ethnicity. Among students, 12.9% did not drink any soda during the previous 7 days, 50.4% drank some soda, but less than 1 per day, and 10.7% drank 1 soda per day. Items did not probe specifically as to whether sodas were sugar containing or sugar- substitute diet drinks.

Daily Breakfast Consumption. Almost half (46.6%) of middle school students reported eating breakfast every day during the previous 7 days. There were statistically significant differences for sex (chi^sup 2^ = 60.7, df = 1, p < .0001), grade level (chi^sup 2^ = 25.7, df = 2, p < .0001), and ethnicity (chi^sup 2^ = 59.9, df = 3, p < .0001). More boys (52.4%) than girls (40.9%) ate breakfast every day during the previous 7 days. More sixth graders (52.3%) reported eating breakfast every day during the previous week compared to seventh graders (45.9%) and eighth graders (41.7%). Furthermore, a higher percentage of Hispanic youth (51.8%) and non-Hispanic white youth (51.0%) ate breakfast every day during the previous week compared to non-Hispanic black youth (35.2%).

Physical Activity

Vigorous and Moderate Physical Activity. Almost three fourths (72.3%) of respondents reported that they exercised or participated in physical activity for at least 20 minutes that made them "sweat and breathe hard" on 3 or more days during the past 7 days (vigorous physical activity), and about one third (33.6%) reported that they exercised or participated in physical activity for at least 30 minutes that did not make them sweat and breathe hard (such as fast walking, slow bicycling, skating, pushing a lawn mower, or mopping floors) on 5 or more of the past 7 days (moderate physical activity). Only 7.3% of middle school students reported not engaging in any vigorous or moderate physical activity during the previous 7 days. There were no statistically significant sex or grade-level differences in not engaging in vigorous or moderate physical activity. However, differences were found for ethnicity (chi^sup 2^ = 37.30, df = 3, p < .0001), with more non-Hispanic black youth (11.0%) reporting not engaging in any vigorous or moderate physical activity during the previous 7 days compared to either nonHispanic white youth (5.1%) or Hispanic youth (7.0%). In addition, more other/ multiethnic youth (10.0%) reported not engaging in any vigorous or moderate physical activity during the previous 7 days than non- Hispanic white youth (5.1%). Table 3 provides the point estimates and 95% confidence intervals for no vigorous or no moderate physical activity by sex, grade level, and ethnicity.

PE Class. About 45.1% of middle school students attended PE classes daily, and nearly, 4 (39.9%) of 10 reported not going to PE classes at all during the average school week. Girls were more likely than boys to report not going to PE classes at all during the average school week (chi^sup 2^ = 25.4, df = 1, p < .0001). Hispanic youth (50.8%) were more likely to report not attending daily PE classes compared to non-Hispanic white youth (36.7%), non-Hispanic black youth (37.9%), and other/multiethnic youth (36.4%) (chi^sup 2^ = 33.2, df = 3, p < .0001). Table 3 provides the point estimates and 95% confidence intervals for no PE class attendance by sex, grade level, and ethnicity.

Played Outside After School. Among middle school students, 39.4% reported that they spent most of their time after school going outside and playing. There were statistically significant differences for sex (chi^sup 2^ = 34.9, df = 1, p < .0001), grade level (chi^sup 2^ = 7.3, df = 2, p < .05), and ethnicity (chi^sup 2^ = 67.4, df = 3, p < .0001). More boys (44.9%) than girls (33.8%) played outside; more sixth graders (41.6%) and seventh graders (40.0%) played outside after school than eighth graders (36.5%), and more non-Hispanic white youth (46.4%) played outside after school compared to non-Hispanic black youth (29.6%), Hispanic youth (36.7%), and other/multiethnic youth (36.2%). In addition, more Hispanic youth (36.7%) reported spending time after school playing outside than did non-Hispanic black youth (29.6%). The point estimates and 95% confidence intervals for playing outside after school by sex, grade level, and ethnicity are shown in Table 3. Other activities youth reported spending time doing after school (more than 1 response option could be indicated) included watching television, going online, or playing video games (49.4%); doing homework or studying (46.6%); talking on the telephone (29.3%); doing chores (25.5%); and doing something inside other than watching television, going online, or playing video games (14.0%). Nutrition and Physical Activity Knowledge

Nutrition Knowledge. When youth were asked about the expert recommendation for daily fruit and vegetable consumption, less than one fifth (17.8%) correctly identified consumption of 5 or more servings per day. About one fifth (20.8%) were not sure, and 61.4% answered between 1 and 4 servings per day. There were no statistically significant differences in nutrition knowledge with respect to sex, grade level, or ethnicity. Table 4 contains the relevant point estimates and 95% confidence intervals. When asked to indicate where they had learned about eating healthy (youth could indicate more than 1 response), 62.2% reported learning from their parents, 56.7% reported learning at school, 42.7% said learned from a doctor or a nurse, 31.2% reported learning from television, and 13.7% answered learning from some other source.

Physical Activity Knowledge. Youth were also queried about the expert recommendation for participation in physical activity, with 27.0% correctly identifying the recommendation. There were statistically significant differences for sex (chi^sup 2^ = 43.1, df = 1, p < .0001) and grade level (chi^sup 2^ = 16.2, df = 2, p < .005). Boys (31.2%) were more likely than girls (22.5%) to identify the recommended physical activity level; and a higher percentage of sixth graders (30.4%) correctly identified the physical activity recommendation compared to eighth graders (23.7%). Furthermore, when asked to indicate the perceived benefits of regular physical activity (youth could indicate more than 1 response), 56.6% reported preventing weight problems, 39.1% reported preventing heart problems, 34.8% answered improving mood, and 29% did not know. Table 4 provides the point estimates and 95% confidence intervals for physical activity knowledge by sex, grade level, and ethnicity.

DISCUSSION

Increasing the proportion of youth meeting recommended dietary guidelines is an important strategy in the effort to curb the increasing epidemic of obesity in the United States. Despite widespread dissemination of national initiatives such as "5-A-Day for Better Health" and "3-A-Day of Dairy" to increase daily intake of fruits and vegetables and servings of calcium-rich dairy products, study results revealed that the percentage of middle school youth meeting dietary recommendations for fruit and vegetable intake and milk consumption was low. Only 22.8% of middle school youth consumed at least 5 servings of fruits and vegetables per day, with non-Hispanic white youth and older youth (seventh and eighth graders) being less likely to meet these minimum standards. This finding is troubling in light of strong evidence supporting the protective effect of fruits and vegetables in the prevention of cancer, cardiovascular disease, and obesity.11 This study also found that only 21.9% of middle school youth drank 3 or more glasses of milk per day. Milk consumption among youth is particularly important because milk is the primary source of calcium in children’s diets.12 Moreover, adolescence has been identified as an "once-in-a-lifetime opportunity" for youth to consume calcium at a level sufficient to reduce the risk of bone fracture and osteoporosis in later life.13 This study found that fewer girls and non-Hispanic black youth reported drinking 3 or more glasses of milk per day compared to boys, non-Hispanic white youth, and Hispanic youth. Although low, the percentage of middle school youth meeting dietary recommendations for fruit and vegetable intake (22.8%) was similar to that reported among Florida high school students by the YRBSS (22.0%).14 Milk consumption among middle school students (21.9%) was much higher than that reported by Florida high school students (12.3%).14

This study found that 26.0% of Florida middle school youth drank 2 or more sodas per day during the previous 7 days. Soda consumption is a concern because it increases daily caloric intake with low nutritional value15 and because consumption of soft drinks displaces intake of more nutritious beverages such as milk.16,17 Ludwig et al18 found that after controlling for diet, activity, television, and anthropometrics, each soft drink consumed daily by children 11- 12 years of age over an 18-month period was shown to increase the child’s risk of obesity by 60%. In the current study, more middle school youth consumed 2 or more sodas per day during the past week (26.0%) than the percentage of youth meeting daily dietary recommendations for fruit and vegetable intake (22.8%) and for milk consumption (21.9%). Discouraging soft drink consumption through school board advocacy initiatives19,20 and through modification of the school environment20,21 has been the subject of recent literature. Such considerations seem relevant here for school personnel, given the current findings.

Skipping breakfast contributes to the development of overweight and obesity.22 Youth who skip breakfast have been shown to eat more food later in the day than those who eat breakfast.23 In addition, they may also consume more high-fat snack foods throughout the day.24 The present study found that only 46.6% of middle school students reported eating breakfast every day during the previous 7 days, with fewer girls, seventh and eighth graders, and non- Hispanic black youth reporting daily breakfast consumption. Innovative strategies for promoting breakfast at home or at school appear to be warranted.

Increasing the proportion of youth meeting recommended physical activity guidelines is also a critical step in the fight against obesity. Regular physical activity for adolescents contributes to building and maintaining healthy bones and joints, controlling weight, building lean muscle, reducing fat, and preventing or delaying the development of high blood pressure.25 Among adolescents, physical activity has also been found to be associated with decreased feelings of sadness and lower risk of suicide ideation.26 Current results revealed that 72.3% of middle school youth participated in sufficient vigorous physical activity and 33.6% participated in sufficient moderate physical activity. These estimates are higher than the Florida high school student estimates of 60.8% and 22.3%, respectively.14 Levels of physical activity have been shown to decrease with age in youth and adults alike.27,28 This study also found that girls were less likely than boys to engage in sufficient vigorous and moderate physical activities, and non- Hispanic black youth were less likely to engage in sufficient vigorous physical activity than non-Hispanic white youth. Although only 7.3% of middle school respondents reported not engaging in any vigorous or moderate physical activity during the previous 7 days, non-Hispanic black youth were more likely to report inactivity.

The finding that a smaller proportion of girls than boys engaged in vigorous or moderate physical activity is problematic, especially coupled with the finding that girls were less likely than boys to have had 3 or more daily servings of milk per day. Adolescence is a critical period for bone health because the amount of mineralized bone established during this period is approximately equivalent to the amount lost throughout the remainder of adult life.29 The onset of bone loss in women, even by age 30-35, is a notable health problem.30 Thus, the failure to achieve optimal bone mass during adolescence may compromise bone health later in life. Adequate calcium intake may also be important for maximizing the positive effect of physical activity on bone health during adolescence. Two studies have found that physical activity was more beneficial to bone health in infants and children consuming higher amounts of calcium.31,32 Some girls and young women engage in excessive exercise and eat too little, also putting themselves at risk for low bone mass and fractures.33 Findings from the current study suggest that a risk pattern of low physical activity and low calcium intake already may be establishing itself during childhood and youth.

Healthy People 2010(7) has identified increasing the proportion of adolescents participating in daily school PE as an appropriate behavior change to offset the rise in childhood obesity. The National Association for Sport and Physical Education34 recommends instructional periods totaling 225 minutes per week for middle and secondary school students, translating to five 45-minute periods per week. Regular PE attendance is an excellent intervention to increase student participation in moderate and vigorous levels of physical activity, as well as to provide students with the knowledge, attitudes, and skills to engage in lifelong physical activity.35 This study found that among Florida middle school youth, 45.1% attended PE classes daily and nearly 4 in 10 (39.9%) said that they did not go to PE classes at all during the average school week. Although low, these rates are higher than ones reported by Florida high school youth.14 Because fewer girls and Hispanic youth reported attending PE classes at all, they may be rich foci for physical activity interventions. Initiatives to restore or expand PE requirements would seem to be worthwhile endeavors for school health advocates at the state level. Girls were also less likely to report spending most of their time after school going outside and playing. This study found that 39.4% of middle school youth reported spending most of their time after school going outside to play, with more boys, sixth graders, and non-Hispanic white youth reporting this activity. More youth reported watching television, going online, or playing video games (49.4%), or doing homework/studying (46.6%) after returning home from school than youth who reported going outside to play (39.4%). Parental concerns about neighborhood safety, including worries over traffic and "stranger danger," have been associated with decreases in child outdoor play after school.36

This study also identified significant gaps in youth knowledge of specific dietary and physical activity recommendations. Only 17.8% of respondents could identify the expert recommendation of 5 servings of fruits and vegetables per day, and just 27.0% correctly chose the expert recommendation for daily physical activity. Although students identified parents and schools as their top 2 sources for learning about healthy eating, current dietary messages may be inadequate in scope, placement, or strategy. This point is particularly troubling, given that adherence to dietary and physical activity guidelines is a major thrust of obesity prevention efforts.

CONCLUSIONS

Current dietary and physical activity behaviors and knowledge among Florida middle school youth set the stage for the obesity epidemic to continue. Less than one fourth of youth are meeting expert recommendations for daily fruit and vegetable intake, and less than one fifth correctly identify the daily fruit and vegetable serving recommendation. Youth are also consuming soda in daily quantities that may be displacing more nutrient-dense beverages such as milk. Girls and non-Hispanic black youth consume significantly less milk, potentially placing them at risk for inadequate bone development. In addition, less than half of students report eating breakfast on a daily basis, thereby increasing their likelihood of consuming less nutritious, high-calorie snacks later in the day. Furthermore, although nearly three quarters of middle school youth participate in sufficient levels of vigorous physical activity, only one third meet criteria for participating in sufficient levels of moderate physical activity, and less than half report attending daily PE classes. More girls and Hispanic youth report not attending any PE classes during the average school week.

Despite disappointingly low levels of middle school youth engaging in healthy dietary and physical activity behaviors reported in this study, it is notable to highlight that the prevalence of many behaviors including adequate fruit and vegetable intake, adequate milk consumption, participation in both vigorous and moderate physical activity, and participation in daily PE classes was higher than that reported among Florida high school youth during the same year. For successful future interventions and policies to combat childhood obesity, attention should be given to the waning participation in healthful dietary and physical activity behaviors as youth increase in age. Results from this study reveal participation in healthy dietary and physical activity behaviors among middle school youth that is far from optimal. To make strides in the fight against obesity in the United States, early intervention is needed.

This study has several limitations. First, these data are applicable only to public middle school students and may not pertain to private middle school students or youth not enrolled in public or private education (eg, home-schooled youth). Second, the instrument was not translated into Spanish or any other language; therefore, non-English speaking students did not participate in the survey, and students whose first language was one other than English may have experienced special challenges in reading and interpreting items. Third, no attempt was made at culturally tailoring the instrument for ethno-cultural groups whose foods and dietary customs differ from mainstream practices. Fourth, public school students who completed the YPANS may be different from ones who did not participate in the survey. Fifth, because these were self-reported responses, they are subject to reporting bias. It was not possible to assess the extent of underreporting or overreporting. Future research should consider examination of biomedical measures such as BMI or blood pressure37 in conjunction with dietary and physical activity measures. Sixth, the survey did not ask about family income or attempt to measure the socioeconomic status of respondents. Recent data suggest that youth from poor families may be at higher risk for overweight that those from nonpoor families and that physical inactivity, sweetened beverage consumption, and skipping breakfast may contribute to this disparity.38 Thus, the investigation of family income as it relates to other risk or protective factors may be warranted in future research.

Study strengths include use of a large, state representative sample of Florida public middle school students in grades 6-8; a survey instrument with many comparable items to the YRBSS to facilitate comparison of prevalence; standardized survey administration protocols; and the use of the SUDAAN software to account for the cluster sample of students. This study was also valuable in that it was the first statewide implementation of the YPANS survey to collect dietary and physical activity behavior data among middle school youth. The utility of individual state data related to youth who are overweight or at risk of being overweight has been identified in recent literature as a tool for advocating the update of specific school health policies.39

Dietary and Physical Activity Behaviors of Middle School Youth: The Youth Physical Activity and Nutrition Survey

January 2008 issue of Journal of School Health

Earn 1.0 Continuing Nursing Education Contact Hour

Earn 1.0 CECH Category I CHES, OH0005

1. Current recommendations for physical activity for children and adolescents call for engaging in a minimum of how many minutes of physical activity on most (preferably all) days of the week:

a) 30.

b) 45.

c) 60.

d) 90.

2. The Youth Physical Activity and Nutrition Survey (YPANS) was administered simultaneously with:

a) The Florida Youth Substance Abuse Survey.

b) The Florida Youth Tobacco Survey.

c) No other surveys.

d) Both a and b.

3. The type of parental consent required by most school districts participating in the survey was:

a) Passive.

b) Active.

c) Consensual.

d) Informed.

4. Consumption of fruits and vegetables showed significant differences by:

a) Gender.

b) Grade Level.

c) Ethnicity.

d) Both b and c.

5. The type of milk that respondents drank more than any other was:

a) Whole.

b) 2%.

c) Skim.

d) Flavored.

6. The ethnic group least likely to eat breakfast every day was:

a) Non-Hispanic white youth.

b) Non-Hispanic black youth.

c) Hispanic youth.

d) Other/multiethnic youth.

7. The percentage of respondents reporting not engaging in any vigorous or moderate physical activity during the previous 7 days was:

a) 3.7%.

b) 7.3%.

c) 15.8%.

d) 25.4%.

8. The majority of respondents correctly identified 5 or more servings per day as the recommended daily consumption for fruits and vegetables:

a) True.

b) False.

9. The source of information about healthy eating reported by most respondents was:

a) School.

b) Doctor or nurse.

c) Parent.

d) Television.

10. Girls in the study were significantly less likely than boys to:

a) Attend physical education classes.

b) Spend time after school playing outside.

c) Engage in vigorous or moderate physical activity.

d) Both a and b.

Journal of School Health is written and produced by the American School Health Association. Activity planning, test questions and pilot testing were conducted by Susan F. Wooley, PhD, CHES, and selected members of ASHA’s Editorial Board and Professional Development Committee.

Citation: Zapata LB, Bryant CA, McDermott RJ, Hefelfinger JA. Dietary and physical activity behaviors of middle school youth: the Youth Physical Activity and Nutrition Survey. J Sch Health. 2008; 78: 9-18.

* Indicates CHES and Nursing continuing education hours are available. Also available at www.ashaweb.org/ continuing_education.html

REFERENCES

1. Committee on Prevention of Obesity in Children and Youth. Preventing Childhood Obesity: Health in the Balance. Washington, DC: Institute of Medicine; 2005.

2. Ogden CL, Carroll MD, Curtin LR, et al. Prevalence of overweight and obesity in the United States, 1999-2004. JAMA. 2006;295:1549-1555.

3. Jain A. What Works for Obesity? A Summary of the Research Behind Obesity Interventions. London: BMJ Publishing Group; 2004.

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LAUREN B. ZAPATA, MSPH, PhD(a)

CAROL A. BRYANT, PhD(b)

ROBERT J. MCDERMOTT, PhD, FASHA(c)

JENNIE A. HEFELFINGER, MS(d)

a Research Associate, (lzapata@charter.net), Florida Prevention Research Center, University of South Florida College of Public Health, 13201 Bruce B. Downs Blvd (MDC 056), Tampa, FL 33612-3805.

b Codirector, (cbryant@health.usf.edu), Florida Prevention Research Center, University of South Florida College of Public Health, 13201 Bruce B. Downs Blvd (MDC 056), Tampa, FL 33612-3805.

c Codirector, (rmcdermo@hsc.usf.edu), Florida Prevention Research Center, University of South Florida College of Public Health, 13201 Bruce B. Downs Blvd (MDC 056), Tampa, FL 33612-3805.

d Bureau Chief, (jennie_a_hefelfinger@doh.state.fl.us), Florida Department of Health, Bureau of Chronic Disease Prevention and Health Promotion, 4052 Bald Cypress Way, Tallahassee, FL 32399- 1744.

Address correspondence to: Robert J. McDermott, Codirector, (rmcdermo@hsc.usf.edu), Florida Prevention Research Center, University of South Florida College of Public Health, 13201 Bruce B. Downs Blvd (MDC 056), Tampa, FL 33612-3805.

Copyright American School Health Association Jan 2008

(c) 2008 Journal of School Health, The. Provided by ProQuest Information and Learning. All rights Reserved.