1,993 publications from this institution
Public transit users are expected to have higher levels of active transportation (AT, walking and bicycling) because they often need to walk to and from transit. Surveys in Baltimore and Seattle ( n = 1,622) revealed that transit users performed more AT than nonusers, especially when dependent on transit. Health benefits and impacts of their limited travel options are discussed. Choice transit riders, who use transit and have a car, and dependent transit riders, who are limited to transit use, are compared for differences in AT and leisure physical activity time (LPA). Less LPA is explored as a consequence of the additional AT.
Purpose This study examined covariation among changes in dietary, physical activity, and sedentary behaviors over 12 months among adolescents participating in a health behavior intervention. Evidence of covariation among behaviors would suggest multi-behavior interventions could have synergistic effects. Methods Prospective analyses were conducted with baseline and 12-month assessments from a randomized controlled trial to promote improved diet, physical activity, and sedentary behaviors (experimental condition) or SUN protection behaviors (comparison condition). Participants were adolescent girls and boys (N = 878) aged 11–15 years on entry. The main outcomes were: diet, based on multiple 24-hour recalls (total fat, grams of fiber, servings of fruit and vegetables, total calories); average daily energy expenditure (kcals/kg) based on 7-day physical activity recall interviews; daily minutes of moderate-vigorous physical activity minutes from accelerometery; and self-reported daily hours of sedentary behavior. Results Covariation was found between fat and calories (r = .16), fiber and calories (r = .53), fiber and fruit/vegetables (r = .53), calories and fruit/vegetables (r = .34), and fruit and vegetables and sedentary behavior (r = −.12) for the total sample (all p values < .01). The pattern of findings was similar for most subgroups defined by gender and study condition. Conclusions The strongest covariation was observed for diet variables that are inherently related (calories and fat, fiber, and fruit/vegetables). Little covariation was detected within or between other diet, physical activity and sedentary behavior domains suggesting that interventions to improve these behaviors in adolescents need to include specific program components for each target behavior of interest.
High rates of physical inactivity compromise the health status of populations globally. Social networks have been shown to influence physical activity (PA), but little is known about how best to engineer social networks to sustain PA. To improve procedures for building networks that shape PA as a normative behavior, there is a need for more specific hypotheses about how social variables influence PA. There is also a need to integrate concepts from network science with ecological concepts that often guide the design of in-person and electronically-mediated interventions. Therefore, this paper: (1) proposes a conceptual model that integrates principles from network science and ecology across in-person and electronically-mediated intervention modes; and (2) illustrates the application of this model to the design and evaluation of a social network intervention for PA. A conceptual model for engineering social networks was developed based on a scoping literature review of modifiable social influences on PA. The model guided the design of a cluster randomized controlled trial in which 308 sedentary adults were randomly assigned to three groups: WalkLink+: prompted and provided feedback on participants' online and in-person social-network interactions to expand networks for PA, plus provided evidence-based online walking program and weekly walking tips; WalkLink: evidence-based online walking program and weekly tips only; Minimal Treatment Control: weekly tips only. The effects of these treatment conditions were assessed at baseline, post-program, and 6-month follow-up. The primary outcome was accelerometer-measured PA. Secondary outcomes included objectively-measured aerobic fitness, body mass index, waist circumference, blood pressure, and neighborhood walkability; and self-reported measures of the physical environment, social network environment, and social network interactions. The differential effects of the three treatment conditions on primary and secondary outcomes will be analyzed using general linear modeling (GLM), or generalized linear modeling if the assumptions for GLM cannot be met. Results will contribute to greater understanding of how to conceptualize and implement social networks to support long-term PA. Establishing social networks for PA across multiple life settings could contribute to cultural norms that sustain active living. ClinicalTrials.gov NCT01142804
Purpose. To (1) assess the reliability of the newly developed Fears of Stranger Danger (FSD) scale, (2) examine measurement invariance and identify demographic variation in FSD, and (3) examine associations of FSD with physical activity, screen time, and body mass index (BMI) z score. Design. Cross-sectional survey with test-retest. Setting. Neighborhoods with various socioeconomic characteristics and walkability in San Diego, Boston, and Cincinnati. Participants. Parent-adolescent pairs (n = 171), and parents of children (n = 116). Response rate was 47% for Survey 1, and 69% were retained for Survey 2. Methods. Data analyses included test-retest reliability and internal consistency for FSD, tests of differential functioning for measurement invariance, t-test for associations between FSD and demographic variables, and partial correlation for associations of FSD with physical activity, screen time, and BMI z score. Results. The FSD scale had moderate to substantial test-retest reliability (intraclass correlation coefficient = .65–.85) and excellent internal consistency (Cronbach á = .88–.94). Measurement invariance was established across gender, race/ethnicity, and income. FSD was higher regarding younger children, females, nonwhites, and lower-income youth. FSD was positively associated with restrictive parental rules for playing outside (partial r = .28–.33), and negatively associated with children's outdoor physical activity in the neighborhood (partial r = −.27), but not associated with other measures of physical activity, screen time, or BMI z score. Conclusion. The new measure of FSD had good evidence of reliability and measurement invariance, but there were inconsistent associations of FSD with youth physical activity.
The effects of a 2-year health-related school physical education program on standardized academic achievement scores was assessed in 759 children who completed Metropolitan Achievement Tests before and after the program. Schools were randomly assigned to condition: (a) Specialists taught the Sports, Play, and Active Recreation for Kids curriculum; (b) classroom teachers were trained to implement the curriculum; and (c) controls continued their usual programs. The Trained Teacher condition was superior to Control on Language, Reading, and Basic Battery. The Specialist condition was superior to Control on Reading, but inferior on Language. Despite devoting twice as many minutes per week to physical education as Controls, the health-related physical education program did not interfere with academic achievement. Health-related physical education may have favorable effects on students' academic achievement.
Objective To investigate the effects of two Internet-based weight loss interventions on physical activity (PA) and dietary behaviors using two approaches for computing combined behavior change. Method Participants were 352 overweight/obese women and men completing 12-month interventions in San Diego, California during 2002–2007. Moderate-to-vigorous PA (MVPA) and sedentary time were measured with accelerometers, and dietary fat and fruit and vegetable intake were assessed with food frequency questionnaires. Longitudinal analyses tested the effect of the intervention on combined health behavior change quantified using a standardized residualized change index (SRCI) and a risk factor change index (RFCI). Results At baseline, participants engaged in an average of 153min/week of MVPA and 525min/day of sedentary time, and consumed 37% of calories from fat and <3 fruits and vegetables per day. The interventions had a significant effect on combined behavior change as measured with each approach (p<0.001). The intervention effect was larger (p<0.001) when evaluated using the SRCI (standardized regression coefficient [Beta]=0.30) than the RFCI (β=−0.18). Conclusion Interventions that target both PA and dietary behaviors appear effective. The SRCI was more sensitive for evaluating the intervention, but the RFCI may be easier to use for communicating public health significance.
Project GRAD (Graduate Ready for Activity Daily) evaluates a university course to promote physical activity. In a randomized study, 338 university seniors participated in either an intervention or control course for academic credit, and posttest data were collected on 321. The control course was knowledge-oriented. The intervention course taught behavior change skills in weekly lectures and peer-led labs. Physical activity was assessed with 7-Day Physical Activity Recall interviews. The intervention had no significant effects on men. Among women, the intervention increased total physical activity during leisure, strengthening exercises, and flexibility exercises. This university course had the intended effects of promoting healthful patterns of physical activity among women, but no effects were observed on men, who were more active than women at baseline.
Age-Related Changes in Types and Contexts of Physical Activity in Middle School Girls
