This review examines the evidence that the level of physical activity (PA) or total energy expenditure during adolescence affects body adiposity in the obese and nonobese adolescent population. Several cross-sectional studies suggested that obese children were less physically active than their nonobese peers, but there was no consistent difference in the total energy expenditure. The likelihood that infants of obese mothers become obese at age 1 year is greater if their total energy expenditure (using the doubly labeled water technique) is lower at age 3 months. Many interventional studies in the general adolescent population show a small (1-3% body fat) reduction in adiposity as a result of physical training. It appears, though, that programs longer than one year are more efficacious than shorter programs. Lifestyle activities (e.g., walking to and from school) appear to have a more lasting effect than regimented activities (e.g., calisthenics or jogging).
Oded Bar-Or and Tom Baranowski
Russell Jago, Tom Baranowski and Michael Harris
It is not clear if relationships between GIS obtained environmental features and physical activity differ according to the method used to code GIS data.
Physical activity levels of 210 Boy Scouts were measured by accelerometer. Numbers of parks, trails, gymnasia, bus stops, grocery stores, and restaurants within the commonly used 400 m and 1-mile (1609.3 m) buffers of subject residences and distance to the nearest feature were calculated. Residential density, connectivity, and crime rate were calculated. Regression models with minutes of sedentary, light, or moderate-to-vigorous activity as dependent variables and environmental and demographics as independent variables were run with backward deletion of environmental variables.
Park, crime, and gym variables were associated with physical activity, but relationships varied according to whether a 400 m, 1 mile, or nearest criteria was used.
Environmental variables were associated with the physical activity of adolescent males, but the association was method dependent.
Anthony Barnett, Ester Cerin and Tom Baranowski
A population level increase in physical activity (PA) is critical to reduce obesity in youth. Video games are highly popular and active video games (AVGs) have the potential to play a role in promoting youth PA.
Studies on AVG play energy expenditure (EE) and maintenance of play in youth were systematically identified in the published literature and assessed for quality and informational value.
Nine studies measuring AVG play EE were identified. The meta-analytic estimates of average METs across these studies were 3.1 (95% CI: 2.6, 3.6) to 3.2 (95% CI: 2.7, 3.7). No games elicited an average EE above the 6 MET threshold for vigorous EE. Observed differences between studies were likely due to the different types of games used, rather than age or gender. Four studies related to maintenance of play were identified. Most studies reported AV G use declined over time. Studies were of low-to-medium quality.
AVGs are capable of generating EE in youth to attain PA guidelines. Few studies have assessed sustainability of AV G play, which appears to diminish after a short period of time for most players. Better-quality future research must address how AV G play could be maintained over longer periods of time.
Russell Jago, Tom Baranowski, Debbe Thompson, Janice Baranowski and Kathryn A. Greaves
Little information about relationships between the physical activity and sedentary behaviors of young children is available in the literature. We therefore examined how sedentary behaviors, TV watching, and encouragements and discouragements for activity were associated with physical activity (as measured by observation and heart-rate monitoring) among a tri-ethnic cohort of 149 three- to four-year-old children, which we followed for three years. The results showed that sedentary behavior predicted observed activity in Years 2 and 3 (r = −.672 and −.831, respectively, R 2 = .577 and .775, respectively). Similar results were obtained for heart rate monitoring. Reducing the time children spend in sedentary behavior might result in increased physical activity.
Robert H. DuRant, William O. Thompson, Maribeth Johnson and Tom Baranowski
This follow-up investigation examined the relationship among observed time of television watching, physical activity, and body composition in 5- to 6-year-old children previously studied 2 years ago. Activity level on school and nonschool days was measured with the Children’s Activity Rating Scale. Television watching time was assessed by direct observation, and body composition was measured with the body mass index, skinfold thicknesses, and waist/hip ratio. Television watching behavior, which increased from the earlier study, was not associated with body composition. Physical activity was lower during television watching than nontelevision watching time.
René van Bavel, Gabriele Esposito, Tom Baranowski and Néstor Duch-Brown
Normative messages have been shown to increase intention to do physical activity. We traced how “positive” and “negative” normative messages influenced physical activity intention by comparing constructs of the model of goal-directed behavior with descriptive norms (MGDB + DNs) across control and treatment groups in an experiment. For this purpose, 16–24-year-old respondents (n = 1,200) in Bulgaria, Croatia, and Romania were asked about their age, sex, and levels of physical activity before being exposed to positive and negative normative messages and completing a questionnaire with MGDB + DNs scales. Different MGDB + DNs constructs were influenced by the normative messages: compared with the control, the negative message group showed stronger attitudes (p = .003) and the positive message group showed higher positive anticipated emotions (p = .005). The positive message’s effect is consistent with the literature on conformity to social norms. The negative message’s effect lends itself to interpretations based on social identity and deviance regulation theories.
Frank A. Treiber, Francis McCaffrey, William B. Strong, Harry Davis and Tom Baranowski
This study compared blood pressure and heart rate measurements provided by the Quinton 410 automated exercise monitor with simultaneous auscultatory and electrocardiograph readings during rest, postural change, immediately after each treadmill exercise workload, and during active recovery in a sample of young children (mean age 7.9 yrs). The Quinton 410 provided highly accurate heart rates under all conditions (average mean difference <1.0 bpm). The Quinton systolic readings correlated well with and were similar to auscultation across conditions except for the initial treadmill workload. Slightly weaker relationships were observed between the Quinton and K4 diastolic comparisons. Compared with K4 auscultatory readings, the Quinton 410 provided slightly lower diastolic pressures across conditions (average mean difference = 3.1 mmHg). These findings provide preliminary evidence that for group comparisons with children, the Quinton 410 provides acceptable blood pressure estimates resulting from a variety of events, including exercise.
Jason A. Mendoza, Jessica McLeod, Tzu-An Chen, Theresa A. Nicklas and Tom Baranowski
Childhood obesity is at record high levels in the US and disproportionately affects Latino children; however, studies examining Latino preschool children’s obesity-related risk factors are sparse. This study determined correlates of Latino preschoolers’ (ages 3–5 years) adiposity to inform future obesity interventions and policies.
Latino preschoolers (n = 96) from 4 Head Start centers in Houston, Texas were recruited. Parents reported acculturation and neighborhood safety. Children’s and parents’ height and weight were measured. Children’s television (TV) viewing was measured by TV diaries and physical activity by accelerometers. Linear regression was used with body mass index (BMI) z-score as the dependent variable and covariates sequentially added and retained in 4 blocks: 1) child age, gender, parent education, and BMI; 2) neighborhood safety and parent and child acculturation; 3) TV viewing; and 4) moderate-to-vigorous physical activity (MVPA).
In the final model (n = 96), only neighborhood disorder (β = 0.30, P = .005) and MVPA (β = –0.21, P = .049) were significantly associated with BMI z-score.
Among Latino preschoolers, higher neighborhood disorder and lower MVPA were associated with greater children’s BMI z-scores.
Jason A. Mendoza, Kathy Watson, Nga Nguyen, Ester Cerin, Tom Baranowski and Theresa A. Nicklas
Walking or bicycling to school (ie, active commuting) has shown promise for improving physical activity and preventing obesity in youth. Our objectives were to examine, among US youth, whether active commuting was inversely associated with adiposity and positively associated with moderate-to-vigorous physical activity (MVPA). We also examined whether MVPA mediated the relationships between active commuting and adiposity.
Using data of participants aged 12 to 19 years from the US National Health and Nutrition Examination Survey 2003 to 2004 (n = 789 unweighted), we constructed multiple linear regression models that controlled for dietary energy intake and sociodemographics. The main exposure variable was active commuting. The outcomes were BMI z-score, waist circumference, skinfolds and objectively measured MVPA. The product-of-coefficients method was used to test for mediation.
Active commuting was inversely associated with BMI z-score (β = −0.07, P = .046) and skinfolds (β = −0.06, P = .029), and positively associated with overall daily (β = 0.12, P = .024) and before- and after-school (β = 0.20, P < .001) MVPA. Greater before- and after-school MVPA explained part of the relationship between active commuting and waist circumference (Sobel z = −1.98, P = .048).
Active commuting was associated with greater MVPA and lower measures of adiposity among US youth. Before- and after-school MVPA mediated the relationships between active commuting and waist circumference.
Barbara E. Ainsworth, Carl J. Caspersen, Charles E. Matthews, Louise C. Mâsse, Tom Baranowski and Weimo Zhu
Assessment of physical activity using self-report has the potential for measurement error that can lead to incorrect inferences about physical activity behaviors and bias study results.
To provide recommendations to improve the accuracy of physical activity derived from self report.
We provide an overview of presentations and a compilation of perspectives shared by the authors of this paper and workgroup members.
We identified a conceptual framework for reducing errors using physical activity self-report questionnaires. The framework identifies 6 steps to reduce error: 1) identifying the need to measure physical activity, 2) selecting an instrument, 3) collecting data, 4) analyzing data, 5) developing a summary score, and 6) interpreting data. Underlying the first 4 steps are behavioral parameters of type, intensity, frequency, and duration of physical activities performed, activity domains, and the location where activities are performed. We identified ways to reduce measurement error at each step and made recommendations for practitioners, researchers, and organizational units to reduce error in questionnaire assessment of physical activity.
Self-report measures of physical activity have a prominent role in research and practice settings. Measurement error may be reduced by applying the framework discussed in this paper.