Physical activity behaviours of highly active preschoolers

BACKGROUND

Understanding the physical activity behaviour of young children who are highly active may provide important guidance for promoting physical activity in preschools.

OBJECTIVES

The objective of this study was to describe the movement characteristics of high-active (HA) children during attendance at preschools.

METHODS

Children in 20 preschools (n = 231) wore accelerometers and were classified into tertiles of moderate-to-vigorous physical activity. Children's movement characteristics were observed using the Observational System for Recording Physical Activity in Children-Preschool Version. Mixed-model analyses compared movement types between HA children and lower-active (LA) children during the total school day.

RESULTS

HA (n = 77) children were observed to be more active than LA children (n = 154) indoors (P < 0.001), but no differences were observed outdoors. HA children were more frequently observed running, crawling, climbing, jumping, skipping, swinging and throwing across the total school day than LA children. Outdoors, HA children participated in more swinging and throwing and less jumping or skipping than LA children. Indoors, HA children spent more time pulling, pushing and running, and less time walking than LA children.

CONCLUSIONS

HA children have unique activity patterns. Further interventions to increase physical activity of all preschoolers should increase the time spent outside and include varied activity types throughout the entire school day.

Moderate-to-vigorous physical activity is associated with decreases in body mass index from ages 9 to 15 years

OBJECTIVE

The purpose of this study is to determine whether time spent in objectively measured physical activity is associated with change in body mass index (BMI) from ages 9 to 15.

DESIGN AND METHODS

The participants were enrolled in the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development (n = 938). At ages 9, 11, 12, and 15 the time spent in moderate-to-vigorous physical activity (MVPA) was objectively measured, and BMI was calculated (kg/m(2) ). Longitudinal quantile regression was used to analyze the data. The 10th, 25th, 50th, 75th, and 90th BMI percentiles were modeled as the dependent variables with age and MVPA (h/day) modeled as predictors. Adjustment was also made for gender, race, sleep, healthy eating score, maternal education, and sedentary behavior.

RESULTS

A negative association between MVPA and change in BMI was observed at the 90th BMI percentile (-3.57, 95% CI -5.15 to -1.99 kg/m(2) per hour of MVPA). The negative association between time spent in MVPA and change in BMI was progressively weaker toward the 10th BMI percentile (-0.27, 95% CI -0.62 to 0.07 kg/m(2) per hour of MVPA). The associations remained similar after adjusting for the covariates, and when the analyses were stratified by gender.

CONCLUSION

Time spent in MVPA was negatively associated with change in BMI from age 9 to 15. The association was strongest at the upper tail of the BMI distribution, and increasing time spent in MVPA could help reduce the prevalence of childhood obesity.

After-school setting, physical activity, and sedentary behavior in 5th grade boys and girls

After-school hours are considered critical for children's physical activity (PA) and sedentary behaviors (SB); however, whether the after-school setting influences children's activity patterns is unknown. This study examined the influence of after-school setting (i.e., parent report of the child's usual after-school setting) on 5th grade children's PA and SB, and differences by race/ethnicity. Boys whose parents reported they usually attended an after-school program had higher PA than boys who usually went home after school. A significant interaction between race/ethnicity and after-school setting showed that minority girls whose parents reported they usually attended an after-school program had higher PA and engaged in less SB compared with those who usually went home, whereas the activity patterns of white girls did not differ by after-school setting. Children's usual after-school setting affects their activity patterns; after-school programs may potentially increase PA in boys and minority girls.

Assessing sustainability of Lifestyle Education for Activity Program (LEAP)

Sustained intervention effects are needed for positive health impacts in populations; however, few published examples illustrate methods for assessing sustainability in health promotion programs. This paper describes the methods for assessing sustainability of the Lifestyle Education for Activity Program (LEAP). LEAP was a comprehensive school-based intervention that targeted change in instructional practices and the school environment to promote physical activity (PA) in high school girls. Previous reports indicated that significantly more girls in the intervention compared with control schools reported engaging in vigorous PA, and positive long-term effects on vigorous PA also were observed for girls in schools that most fully implemented and maintained the intervention 3 years following the active intervention. In this paper, the seven steps used to assess sustainability in LEAP are presented; these steps provide a model for assessing sustainability in health promotion programs in other settings. Unique features of the LEAP sustainability model include assessing sustainability of changes in instructional practices and the environment, basing assessment on an essential element framework that defined complete and acceptable delivery at the beginning of the project, using multiple data sources to assess sustainability, and assessing implementation longitudinally.

Physical activity in overweight and nonoverweight preschool children

OBJECTIVE

To compare the physical activity levels of overweight and non overweight 3- to 5-y-old children while attending preschool. A secondary aim was to evaluate weight-related differences in hypothesized parental determinants of child physical activity behavior.

DESIGN

Cross-sectional study.

SUBJECTS

A total of 245, 3- to 5-y-olds (127 girls, 118 boys) and their parent(s) (242 mothers, 173 fathers) recruited from nine preschools. Overweight status determined using the age- and sex-specific 85th percentile for body mass index (BMI) from CDC Growth Charts.

MEASUREMENTS

Physical activity during the preschool day was assessed on multiple days via two independent objective measures-direct observation using the observation system for recording activity in preschools (OSRAP) and real-time accelerometry using the MTI/CSA 7164 accelerometer. Parents completed a take-home survey assessing sociodemographic information, parental height and weight, modeling of physical activity, support for physical activity, active toys and sporting equipment at home, child's television watching, frequency of park visitation, and perceptions of child competence.

RESULTS

Overweight boys were significantly less active than their nonoverweight peers during the preschool day. No significant differences were observed in girls. Despite a strong association between childhood overweight status and parental obesity, no significant differences were observed for the hypothesized parental influences on physical activity behavior.

CONCLUSIONS

Our results suggest that a significant proportion of overweight children may be at increased risk for further gains in adiposity because of low levels of physical activity during the preschool day.

Factorial invariance and latent mean structure of questionnaires measuring social-cognitive determinants of physical activity among black and white adolescent girls

BACKGROUND

We previously developed questionnaires based on contemporary theories to measure physical activity determinants among youth [Motl et al., Prev Med 2000; 31:584-94]. The present study examined the factorial invariance and latent mean structure of unidimensional models fit to the questionnaires measuring attitude, subjective norm, perceived behavioral control, and self-efficacy about physical activity among black and white adolescent girls.

METHODS

Black (n = 896) and white (n = 823) girls in the 8th grade completed the questionnaires measuring attitude, subjective norm, perceived behavioral control, and self-efficacy about physical activity. The responses were subjected to analyses of factorial invariance and latent mean structure using confirmatory factor analysis with full-information maximum likelihood estimation in AMOS 4.0.

RESULTS

The unidimensional models of the four questionnaires generally demonstrated invariance of the factor structure, factor loadings, and factor variance across race but not invariance of the variance-covariance matrices or item uniquenesses. The analyses of latent mean structure demonstrated that white girls had higher latent mean scores on the measures of attitude and self-efficacy than black girls; there were similar, but smaller, differences between white and black girls on the measures of subjective norm and perceived behavioral control.

CONCLUSIONS

The questionnaires can be employed in interventions to test the mediating influences of attitude, subjective norm, perceived behavioral control, and self-efficacy on participation in physical activity by black and white adolescent girls.

Measuring enjoyment of physical activity in adolescent girls

BACKGROUND

Enjoyment has been implicated as a determinant of physical activity among youth, but advances in understanding its importance have been limited by the use of measures that were not adequately validated. The present study examined: (1) the factorial validity of the Physical Activity Enjoyment Scale (PACES), and (2) the construct validity of PACES scores.

METHODS

Adolescent girls (N=1797), who were randomly assigned to calibration (n=899) and cross-validation (n=898) samples, completed the PACES and measures of factors influencing enjoyment of physical education, physical activity, and sport involvement. The factorial validity of the PACES and the measure of factors influencing enjoyment of physical education was tested using exploratory and confirmatory factor analysis. The hypothesized relationships among the measures were tested using structural equation modeling.

RESULTS

Unidimensional models fit the PACES and the measure of factors influencing enjoyment of physical education in the calibration and cross-validation samples. The hypothesized relationships between the PACES and the measures of factors influencing enjoyment of physical education, physical activity, and sport involvement were supported in the entire sample, were similar in African-American and Caucasian girls, and were independent of physical fitness.

CONCLUSIONS

Evidence of factorial validity and convergent evidence for construct validity indicate that the PACES is a valid measure of physical activity enjoyment among adolescent girls, suitable for use as a mediator variable in interventions designed to increase physical activity.

Environmental influences, physical activity, and weight status in 8- to 16-year-olds

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.

Factorial validity and invariance of questionnaires measuring social-cognitive determinants of physical activity among adolescent girls

BACKGROUND

There are few theoretically derived questionnaires of physical activity determinants among youth, and the existing questionnaires have not been subjected to tests of factorial validity and invariance. The present study employed confirmatory factor analysis (CFA) to test the factorial validity and invariance of questionnaires designed to be unidimensional measures of attitudes, subjective norms, perceived behavioral control, and self-efficacy about physical activity.

METHODS

Adolescent girls in eighth grade from two cohorts (N = 955 and 1,797) completed the questionnaires at baseline; participants from cohort 1 (N = 845) also completed the questionnaires in ninth grade (i.e., 1-year follow-up). Factorial validity and invariance were tested using CFA with full-information maximum likelihood estimation in AMOS 4.0. Initially, baseline data from cohort 1 were employed to test the fit and, when necessary, to modify the unidimensional models. The models were cross-validated using a multigroup analysis of factorial invariance on baseline data from cohorts 1 and 2. The models then were subjected to a longitudinal analysis of factorial invariance using baseline and follow-up data from cohort 1.

RESULTS

The CFAs supported the fit of unidimensional models to the four questionnaires, and the models were cross-validated, as indicated by evidence of multigroup factorial invariance. The models also possessed evidence of longitudinal factorial invariance.

CONCLUSIONS

Evidence was provided for the factorial validity and the invariance of the questionnaires designed to be unidimensional measures of attitudes, subjective norms, perceived behavioral control, and self-efficacy about physical activity among adolescent girls.

Sports participation and health-related behaviors among US youth

OBJECTIVE

To examine the relationship between sports participation and health-related behaviors among high school students.

DESIGN

Cross-sectional design using data from the 1997 Centers for Disease Control and Prevention Youth Risk Behavior Survey.

PARTICIPANTS

A nationally representative sample of 14,221 US high school students.

MAIN OUTCOME MEASURES

Prevalence of sports participation among males and females from 3 ethnic groups and its associations with other health behaviors, including diet, tobacco use, alcohol and illegal drug use, sexual activity, violence, and weight loss practices.

RESULTS

Approximately 70% of male students and 53% of female students reported participating on 1 or more sports teams in school and/or nonschool settings; rates varied substantially by age, sex, and ethnicity. Male sports participants were more likely than male nonparticipants to report fruit and vegetable consumption on the previous day and less likely to report cigarette smoking, cocaine and other illegal drug use, and trying to lose weight. Compared with female nonparticipants, female sports participants were more likely to report consumption of vegetables on the previous day and less likely to report having sexual intercourse in the past 3 months. Among white males and females, several other beneficial health behaviors were associated with sports participation. A few associations with negative health behaviors were observed in African American and Hispanic subgroups.

CONCLUSION

Sports participation is highly prevalent among US high school students, and is associated with numerous positive health behaviors and few negative health behaviors.

Tracking of avoidance of alcohol use and smoking behavior in a fifth grade cohort over three years

This study examined the maintenance of positive health behavior (avoidance of alcohol use and cigarette smoking) and factors associated with the maintenance of these behaviors from fifth through seventh grade by a cohort of rural students (N = 232). African American and White students showed similar patterns of high avoidance of alcohol until seventh grade. Although more girls avoided use than boys, avoidance decreased in both groups with progression in grade. Mothers', fathers', and best friends' drinking behaviors influenced avoidance behavior; drinking was less likely to occur among those whose parents and friends did not drink. Friends' drinking behavior influenced alcohol use as early as fifth grade. Smoking avoidance was maintained by 74% of the students over the 3 years. Although there were no racial differences in smoking, African Americans started smoking about 1 year earlier than Whites. During seventh grade, an increase in smoking occurred among boys and girls, but was particularly striking among girls. Avoidance of smoking was influenced by mothers' behavior but not fathers'. Best friends' smoking behavior exerted a major influence on avoidance between grades 6 and 7. In grades 5 and 6, those who avoided smoking were more physically active than smokers, but by seventh grade their physical activity declined to a similar level as smokers. Rural adolescent boys seemed to be at early risk for alcohol use and smoking, while rural girls delayed involvement by 1 to 2 years. Communities, schools, and families can help adolescents avoid alcohol use and smoking through early prevention efforts.

Health risk behaviors of rural sixth graders

The purposes of this study were to examine the frequency and risk factors (correlates) of single and concurrent health risk behaviors (HRBs) including obesity, physical inactivity, smoking, and alcohol use in a sample of 352 rural, predominately African-American sixth graders. This study was guided by Jessor's (1992) adolescent risk behavior conceptual framework. Data were collected using physical measures and a self-report questionnaire. Thirty-two percent of the sample had no HRB, 44% had one HRB, and 24% had two or more HRBs. Obesity and physical inactivity were more prevalent in this sample than in the general population. Gender differences in risk factors were evident. Our findings suggest the testing of interventions that focus on the social needs of girls and that influence behavioral modeling for boys to reduce single and concurrent health risk behaviors.

Correlates of hepatotoxicity and antituberculosis therapy in South Carolina

This study revealed that 20-30 percent of TB patients who were taking antituberculosis therapy developed elevated liver function tests. Half of the elevation in liver enzyme values occurred within the first two months of treatment. No statistically significant differences between sex, race and liver toxicity was found in this study. The time from initiation of treatment for TB to development of hepatotoxicity was shorter for females and whites. Physicians and public health workers should monitor the liver function tests of TB patients who are taking antituberculosis treatment. Recommendations for monitoring hepatotoxicity vary depending on the age of the patients. For patients less than 35 years old, monthly symptom review for jaundice, acholic stools, fever, anorexia, nausea and vomiting, may be adequate. For older patients, liver function tests are recommended monthly or every one to two months.

Physical activity and physical fitness in African-American girls with and without obesity

Lack of physical activity and low levels of physical fitness are thought to be contributing factors to the high prevalence of obesity in African-American girls. To examine this hypothesis, we compared habitual physical activity and physical fitness in 54 African-American girls with obesity and 96 African-American girls without obesity residing in rural South Carolina. Participation in vigorous (> or = 6 METs) (VPA) or moderate and vigorous physical activity (> or = 4 METs) (MVPA) was assessed on three consecutive days using the Previous Day Physical Activity Recall. Cardiorespiratory fitness was assessed using the PWC 170 cycle ergometer test. Upper body strength was determined at two sites via isometric cable tensiometer tests. Relative to their counterparts without obesity, girls with obesity reported significantly fewer 30-minute blocks of VPA (0.90 +/- 0.14 vs. 1.3 +/- 0.14) and MVPA (1.2 +/- 0.18 vs. 1.7 +/- 0.16) (p < 0.01). Within the entire sample, VPA and MVPA were inversely associated with body mass index (r = -0.17 and r = -0.19) and triceps skinfold thickness (r = -0.19 and r = -0.22) (p < 0.05). In the PWC 170 test and isometric strength tests, girls with obesity demonstrated absolute scores that were similar to, or greater than, those of girls without obesity; however, when scores were expressed relative to bodyweight, girls with obesity demonstrated significantly lower values (p < 0.05). The results support the hypothesis that lack of physical activity and low physical fitness are important contributing factors in the development and/or maintenance of obesity in African-American girls.

Correlates of physical activity behavior in rural youth

The purpose of this study was to identify correlates of physical activity behavior in a sample of rural, predominantly African American youth. Three hundred sixty-one fifth-grade students from two rural counties in South Carolina (69% African American, median age = 11 years) completed a questionnaire designed to measure beliefs and social influences regarding physical activity, physical activity self-efficacy, perceived physical activity habits of family members and friends, and access to exercise and fitness equipment at home. After school physical activity and television watching were assessed using the Previous Day Physical Activity Recall (PDPAR). Students were classified as physically active according to a moderate physical activity standard: two or more 30-min blocks at an intensity of 3 METs (metabolic equivalents) or greater, and a vigorous physical activity standard: one or more 30-min blocks at an intensity of 6 METs or greater. According to the moderate physical activity standard, 34.9% of students were classified as low-active. Multivariate analysis revealed age, gender, television watching, and exercise equipment at home to be significant correlates of low activity status. According to the vigorous physical activity standard, 32.1% of the students were classified as low-active. Multivariate analysis revealed age, gender, television watching, and self-efficacy with respect to seeking support for physical activity to be significant correlates of low activity status. In summary, gender and the amount of television watching were found to be the most important correlates of physical activity in rural, predominantly African American youth.

A prospective study of the determinants of physical activity in rural fifth-grade children

BACKGROUND

Understanding the factors that influence physical activity behavior is important in the design of intervention programs targeted at youth.

METHODS

A prospective study design was used to identify the predictors of vigorous physical activity (VPA) (> or = 6 METs) and moderate and vigorous physical activity (MVPA) (> or = 3 METs) among 202 rural, predominantly African-American children. Selected social-cognitive determinants of physical activity were assessed via questionnaire in the fifth grade. Participation in VPA and MVPA was assessed via the previous day physical activity recall 1 year later in the sixth grade.

RESULTS

For girls, participation in community sports, self-efficacy in overcoming barriers, enjoyment of school physical education, race (white > black), and perception of mother's activity level (active vs inactive) were significant predictors of VPA. For MVPA, participation in community sports and self-efficacy in overcoming barriers were significant predictors. For boys, self-efficacy in overcoming barriers was the only significant predictor of VPA, while beliefs regarding activity outcomes and participation in community sports were significant predictors of MVPA.

CONCLUSION

Social-cognitive constructs such as physical activity self-efficacy, access to community physical activity outlets, and positive beliefs regarding physical activity outcomes are important predictors of future physical activity behavior among rural, predominantly African-American children.

Development of questionnaires to measure psychosocial influences on children's physical activity

BACKGROUND

The purpose of this study was to develop and validate questionnaires used to measure psychosocial determinants of physical activity in preadolescent children.

METHODS

Three theory-based questionnaires and a measure of after-school physical activity were administered to 422 fifth-grade students. A cross-validation design was employed for psychometric development of the scales, including factor analysis, reliability, and validation by correlating scale scores with intention to be physically active and after-school physical activity.

RESULTS

The Social Influences scale contained a single factor. The Self-Efficacy scale contained three factors: support seeking, barriers, and positive alternatives. The Beliefs scale contained two factors: social outcomes and physical activity outcomes. Reliability coefficients ranged from about 0.50 to 0.78. Significant correlations were obtained between all six scales and intention in the development sample, and between five scales and intention in the validation sample. Significant correlations were obtained between social influence and self-efficacy barriers and physical activity in the development sample, and between social influences and physical activity in the validation sample.

CONCLUSIONS

Three scales to measure psychosocial determinants of physical activity were refined for use with rural, predominantly African-American, preadolescent children, and shown to be both reliable and valid. Factor analysis resulted in interpretable subscales that may be used as variables. These preliminary results provide support for using the scales to measure influences on activity in children.

Associations between physical activity and other health behaviors in a representative sample of US adolescents

OBJECTIVES

This study examined the associations between physical activity and other health behaviors in a representative sample of US adolescents.

METHODS

In the 1990 Youth Risk Behavior Survey, 11631 high school students provided information on physical activity; diet; substance use; and other negative health behaviors. Logistic regression analyses examined associations between physical activity and other health behaviors in a subset of 2652 high-active and 1641 low-active students.

RESULTS

Low activity was associated with cigarette smoking, marijuana use, lower fruit and vegetable consumption, greater television watching, failure to wear a seat belt, and low perception of academic performance. For consumption of fruit, television watching, and alcohol consumption, significant interactions were found with race/ethnicity or sex, suggesting that sociocultural factors may affect the relationships between physical activity and some health behaviors.

CONCLUSIONS

Low physical activity was associated with several other negative health behaviors in teenagers. Future studies should examine whether interventions for increasing physical activity in youth can be effective in reducing negative health behaviors.

Factors affecting fibrinolytic potential: cardiovascular fitness, body composition, and lipoprotein(a)

The purpose of the study was to determine the factors that affect basal (resting) and poststressor fibrinolytic activity or potential. Variables of interest included cardiovascular fitness (maximal oxygen consumption [Vo2max]), body fat, body mass index (BMI), and lipids/lipoproteins, including lipoprotein(a) [Lp(a)]. Blood was collected from 46 middle-aged men before and after a maximal exercise test. Pearson and Spearman correlation coefficients were calculated to determine associations between the variables of interest and tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) activities in the basal state and after stimulation with maximal exercise. Multiple regression analyses were also conducted to determine independent predictors of the fibrinolytic variables. Maximal exercise produced significant increases in t-PA activity and decreases in PAI-1 activity. Postexercise t-PA activity was inversely related to basal PAI-1 activity (r = -.34). Vo2max was positively correlated with t-PA activity (basal, r = .39; postexercise, r = .67) and inversely related to PAI-1 activity (basal, r = -.41; postexercise, r = -.42). Body fat was correlated with postexercise t-PA activity (r = -.60) and both basal and postexercise PAI-1 activity (r = .42), but the correlation with basal t-PA activity was not significant (P = .058). Postexercise t-PA activity was positively correlated (r = .37) with high-density lipoprotein cholesterol (HDL-C) and negatively correlated (r = -.42) with low-density lipoprotein cholesterol (LDL-C). Basal PAI-1 activity was negatively correlated with HDL-C (r = -.37), Lp(a) was not correlated with any fibrinolytic variable or fitness. Multiple regression analyses showed that Vo2max was an independent predictor of both basal and postexercise t-PA activity (R2 = .16 and .34, respectively). Triglyceride (TG) levels and Vo2max were significant independent predictors of PAI-1 activity (R2 = .31). In conclusion, cardiovascular fitness was a strong independent predictor of fibrinolytic potential. In addition, poststressor measures of fibrinolytic potential may provide more information about the fibrinolytic system than basal values.

Predictors of Alcohol Use Among Rural Adolescents

There is increasing evidence that alcohol use is becoming more common during childhood and early adolescence. However, little is known about alcohol use among rural youths. This article reports a study of alcohol use among 367 fifth-grade students in two rural South Carolina school districts. More than one third (n = 131) of the fifth graders reported having used alcohol. Of these, 34 percent (n = 44) reported drinking during the previous month; 8 percent had been intoxicated during the previous two months; and 54 percent reported drinking in the home with or without parental approval. Logistic regression analysis was used to determine the predictors of alcohol use by fifth graders. The results indicated that gender (OR = 2.82), mother's alcohol use (OR = 1.86), father's alcohol use (OR = 2.13), and smoking (OR = 8.30) were significantly associated with alcohol use. The findings suggest that prevention programs address cigarette smoking and drinking behaviors of parents to reduce alcohol use and the acquisition of other health compromising behavior by youths. Early intervention approaches must go beyond the schools and target families as well as community populations.

Gender differences in physical activity and determinants of physical activity in rural fifth grade children

This study determined if gender differences in physical activity could be accounted for by differences in selected social-cognitive determinants of activity behavior. Some 334 fifth grade, predominantly African-American students provided information regarding after-school physical activity and the hypothesized determinants of activity behavior. Boys reported significantly greater participation in vigorous ( > or = 6 METs) and in moderate to vigorous ( > or = 4 METs). Relative to girls, boys demonstrated higher levels of physical fitness, greater self-efficacy in overcoming barriers to physical activity, greater amounts of television watching, and higher levels of participation in community sports and physical activity organizations. When mean physical activity scores for girls and boys were adjusted for the effects of these determinant variables, the significant gender difference in physical activity remained. However, adjustment for self-efficacy in overcoming barriers and community sports reduced the gender gap by 5% and 7%, respectively. In contrast, adjustment for television watching increased the gender gap by about 8%. Results indicated perceived confidence in overcoming barriers to physical activity and participation in community physical activity programs are factors related to the gender difference in physical activity.

Tracking of physical activity in young children

The purpose of this study was to determine whether physical activity behavior tracks during early childhood. Forty-seven children (22 males, 25 females) aged 3-4 yr at the beginning of the study were followed over a 3-yr period. Heart rates were measured at least 2 and up to 4 d.yr-1 with a Quantum XL Telemetry heart rate monitor. Physical activity was quantified as the percentage of observed minutes between 3:00 and 6:00 p.m. during which heart rate was 50% or more above individual resting heart rate (PAHR-50 Index). Tracking of physical activity was analyzed using Pearson and Spearman correlations. Yearly PAHR-50 index tertiles were created and examined for percent agreement and Cohen's kappa. Repeated measures ANOVA was used to calculate the intraclass correlation coefficient across the 3 yr of the study. Spearman rank order correlations ranged from 0.57 to 0.66 (P < 0.0001). Percent agreement ranged from 49% to 62%. The intraclass R for the 3 yr was 0.81. It was concluded that physical activity behavior tends to track during early childhood.

A comparison of questionnaire and physiological data in predicting future chronic disease risk factor status in an employee population

BACKGROUND

The ideal screening tool for worksite health screening programs has not yet been identified, and the effectiveness of screening programs in predicting future chronic disease risk factors status is not well understood. This study compared two commonly used screening tools, health-related questionnaires and measurement of physiological parameters, in terms of their ability to predict future chronic disease risk factor status in an employee population.

METHODS

Data were collected over a 10-year period from Liberty Corporation employees (N = 723). Baseline evaluation included the administration of questionnaires and measurement of physiological data. Follow-up evaluation measured physiological data only. Regression analyses identified the statistically significant predictors of future risk factor status using 1) baseline questionnaire data; 2) baseline physiological data; and 3) both questionnaire and physiological data as predictor variables.

RESULTS

Although both screening methods were able to predict future risk factor status, R 2 values were higher in models including baseline physiological measures than models including questionnaire data only. Adding questionnaire data to physiological data provided little or no additional predictive ability.

DISCUSSION

These results suggest that physiological data, particularly baseline measures of a risk factor, are more predictive of future risk factor status than questionnaire data.

Reliability of long-term recall of participation in physical activity by middle-aged men and women

The reliability of long-term recall of physical activity participation was examined in 322 women and 129 men in a worksite health study conducted at the Liberty Corporation, Greenville, South Carolina during 1976-1987. Leisure time physical activity was assessed at baseline; and energy expenditure in total, light, moderate, and vigorous activities was calculated. The long-term recall of baseline activities was determined 1-10 years after the examination. The relation between actual baseline and recalled activity was positive and in most cases the coefficients were statistically significant at p less than 0.05. The correlations were modest, most in the range of 0.20 to 0.50. Percent agreement between baseline and recalled activity generally ranged from 60 to 75%. Multiple regression analyses suggested that recalled activity was a significant predictor of baseline activity, but recall interval and age were not important contributors to the regression model. R2 values for the model were 0.10 for light activity and 0.26 for vigorous activity. Questionnaire assessment of long-term physical activity recall appeared to be reliable, length of recall interval up to 10 years was not an important factor, and recall of vigorous activity was more accurate than for less intensive activities.

Associations between physical activity and physical fitness in American children

Associations between two measures of physical fitness, 1.6-km run/walk performance and sum of three skinfold thicknesses, and selected physical activity factors were studied in a nationally representative sample of third- and fourth-grade students (1150 boys, 1202 girls). Twenty physical activity variables measured via parent and teacher questionnaires were factor analyzed, and for each of the resultant eight factors, individual factor scores were generated. These were used in two multiple regression analyses in which 1.6-km run/walk time and sum of skinfold measurements were the dependent variables. Multiple R2 for these two analyses were .21 and .18. Significant factors in both analyses were global ratings of the child's activity level, age, vigorous community activities, and gender. The results indicate that physical activity and physical fitness are significantly, although moderately, associated in young children and suggest that interventions directed toward enhancement of physical activity in children are worthy of investigation.