The Physical Activity Patterns of Greenway Users Playing Pokémon Go: A Natural Experiment.

OBJECTIVE: The aim of the study was to compare objectively measured physical activity (PA) between greenway users playing and not playing Pokémon Go. MATERIALS AND METHODS: A sample of 100 participants walking on a greenway wore an Omron pedometer and ActiGraph accelerometer and provided demographic data through an intercept survey during a natural experiment. Mann-Whitney U tests and multiple regression compared greenway PA variables between Pokémon Go (n = 13) and non-Pokémon Go (n = 87). RESULTS: Pokémon Go users were significantly younger (P < 0.01) than non-Pokémon Go users. Despite no differences in greenway walking time (42 ± 18 minutes), Pokémon Go users took fewer aerobic steps (2361 ± 1663 steps vs. 4144 ± 2591 steps; P = 0.03), walked shorter distances (1.38 ± 0.68 miles vs. 1.98 ± 1.05 miles; P = 0.049), burned fewer calories (119 ± 79 kcal vs. 202 ± 158 kcal; P = 0.04), spent more time in sedentary (16% ± 12% vs. 2% ± 7%; P < 0.01) and light (29% ± 24% vs. 15% ± 21%; P < 0.01) intensity activity, less time in moderate (52% ± 30% vs. 71 ± 29%; P = 0.02) and moderate-to-vigorous PA (MVPA) (55% ± 29% vs. 82% ± 23%; P < 0.01), and took fewer steps/min (67 ± 24 steps/min vs. 103 ± 23 steps/min; P < 0.01) than non-Pokémon Go users. Pokémon Go step rate rarely exceeded 100 steps/min for >5 minutes at a time. Multiple regression confirmed differences in sedentary, light, vigorous, MVPA, and steps/min between Pokémon Go and non-Pokémon Go users after controlling for covariates (P < 0.05). Age was significantly positively associated with aerobic steps, steps, walking distance and time, more light, but less vigorous, and MVPA (P < 0.05). CONCLUSION: While playing Pokémon Go greenway users are likely stopping more and walking at a slower pace than walkers not playing Pokémon Go.

The Modifying Effects of Race/Ethnicity and Socioeconomic Status on the Change in Physical Activity From Elementary to Middle School.

PURPOSE: Youth physical activity (PA) levels differ by race/ethnicity and socioeconomic status (SES). It is well established that various multilevel factors may influence changes in PA. The present study examined whether the association between the change in individual, interpersonal, and environmental factors and the change in PA is modified by race/ethnicity or SES. METHODS: This study followed 643 youths and their parents from suburban and rural South Carolina participating in the Transitions and Activity Changes in Kids (TRACK) Study in 2008-2009 and 2010-2011. We assessed total PA in youth using accelerometry and categorized youth and parent survey data into blocks based on the socioecological model. Multivariate regression growth curve models evaluated whether the association between change in independent variables and change in PA was modified by race/ethnicity or SES. RESULTS: PA declined from fifth to seventh grade among all racial/ethnic and SES groups. Associations between the range of variables and change in PA were modified by race/ethnicity but not SES. Blacks did not share any common predictors of change in PA with whites or Hispanics. However, child-reported number of active friends was associated with total PA, and enjoyment of PA was associated with change in PA among both whites and Hispanics. Significant interactions by time varied by racial/ethnic group. CONCLUSIONS: The factors that influence changes in youth PA vary by race/ethnicity but not SES. These findings reinforce the complex nature of addressing PA behavior in diverse samples and further support the need for culturally appropriate interventions to promote PA in youth.

What is really causing the obesity epidemic? A review of reviews in children and adults.

Obesity prevention is a public health priority and intervention strategies have focused primarily on healthy eating and physical activity in children and adults. To date, no review has systematically compiled and synthesised the scientific evidence from published review articles to determine whether there is clear consensus on the causes of obesity. A systematic review of the literature was conducted searching PubMed/Medline for narrative and systematic review articles published between January 1990 and October 2014 that examined the causes of obesity. In total, 12 of 65 articles met the inclusion criteria; 7 reviews focused on adults (1 systematic, 6 narrative) and 5 reviews on children (2 systematic, 3 narrative). The most popular cause of obesity identified in reviews of adult studies was "combined physical activity and diet" (3 of 7 studies), whereas the most popular cause specified in reviews of child studies was deemed "inconclusive" (2 of 5 studies). While a number of reviews have examined the causes of obesity, the methodology and conclusions varied widely, and few were conducted systematically. Currently, no consensus exists across published literature reviews regarding the primary cause of the obesity epidemic, and more research, particularly prospective studies using state-of-the-art measures, is warranted.

Policies for promotion of physical activity and prevention of obesity in adolescence.

Obesity rates among children and adolescents in developed countries have increased dramatically since the 1970s. During that same period, numerous secular changes have combined to reduce the demand for physical activity in day-to-day life, and many barriers to physical activity are now evident. As a consequence, most children and adolescents do not meet the accepted public health guidelines for physical activity. Accordingly, public health interventions are needed to increase physical activity in adolescence. Such interventions, if successfully implemented, can be expected to improve fitness and health as well as reduce the prevalence of overweight and obesity in young people. Promotion of physical activity in populations of children and adolescents will require comprehensive strategic planning and adoption of new policies in multiple societal sectors. This paper highlights nine initiatives that can address the problem of physical activity in children. The initiatives are to: establish comprehensive school physical activity programming; demand high quality physical education; require physical activity in early child care and education; require physical activity in afterschool programs; create equity in community resources; activate youth sports programs; re-normalize active transport to school; institutionalize clinic-based physical activity assessment and counseling; and build activity-friendly homes. A case will be made for comprehensive national and international strategic planning aimed at effective and large-scale implementation of these initiatives and tactics.

Estimating physical activity in youth using a wrist accelerometer.

PURPOSE: The purpose of this study was to develop and validate methods for analyzing wrist accelerometer data in youth. METHODS: A total of 181 youth (mean ± SD; age, 12.0 ± 1.5 yr) completed 30 min of supine rest and 8 min each of 2 to 7 structured activities, selected from a list of 25. Receiver operating characteristic (ROC) curves and regression analyses were used to develop prediction equations for energy expenditure (child-METs; measured activity V˙O2 divided by measured resting V˙O2) and cut points for computing time spent in sedentary behaviors (SB), light (LPA), moderate (MPA), and vigorous (VPA) physical activity. Both vertical axis (VA) and vector magnitude (VM) counts per 5 s were used for this purpose. The validation study included 42 youth (age, 12.6 ± 0.8 yr) who completed approximately 2 h of unstructured PA. During all measurements, activity data were collected using an ActiGraph GT3X or GT3X+, positioned on the dominant wrist. Oxygen consumption was measured using a Cosmed K4b. Repeated-measures ANOVA were used to compare measured versus predicted child-METs (regression only) and time spent in SB, LPA, MPA, and VPA. RESULTS: All ROC cut points were similar for area under the curve (≥0.825), sensitivity (≥0.756), and specificity (≥0.634), and they significantly underestimated LPA and overestimated VPA (P < 0.05). The VA and VM regression models were within ±0.21 child-METs of mean measured child-METs and ±2.5 min of measured time spent in SB, LPA, MPA, and VPA, respectively (P > 0.05). CONCLUSIONS: Compared to measured values, the VA and VM regression models developed on wrist accelerometer data had insignificant mean bias for child-METs and time spent in SB, LPA, MPA, and VPA; however, they had large individual errors.

Detecting indoor and outdoor environments using the ActiGraph GT3X+ light sensor in children.

INTRODUCTION: Experts recommend children spend more time playing outdoors. The ambient light sensor of the ActiGraph GT3X+ provides lux measurements. A lux is the International System's unit of illumination, equivalent to 1 lm·m. Few studies have established a lux threshold for determining whether a child is indoors or outdoors. PURPOSE: This study aimed 1) to assess the reliability of the ActiGraph GT3X+ ambient light sensor, 2) to identify a lux threshold to accurately discriminate between indoor and outdoor activities in children, and 3) to test the accuracy of the lux threshold in a free-living environment. METHODS: In part 1, a series of reliability tests were performed using 20 ActiGraph GT3X+ monitors under different environmental conditions. Cronbach's alpha was used to determine interinstrument reliability. In part 2, 18 children performed 11 different activities (five indoors and six outdoors) for 6 min each. The optimal threshold for detecting indoor/outdoor activity was determined using a receiver operator characteristic curve analysis. In part 3, 18 children at a preschool wore the monitor during a school day. Percent accuracy was determined for all conditions. RESULTS: In part 1, the devices had Cronbach's alpha values of 0.992 and 1.000 for indoor and outdoor conditions, respectively, indicating high interinstrument reliability. In part 2, the optimal lux threshold was determined to be 240 lux (sensitivity = 0.92, specificity = 0.88, area under the curve = 0.96, 95% CI = 0.951-0.970). In part 3, results of the school-day validation demonstrated the monitor was 97.0% accurate for overall detection of indoor and outdoor conditions (outdoor = 88.9%, indoor = 99.1%). CONCLUSIONS: The results demonstrate that an ActiGraph GT3X+ lux threshold of 240 can accurately assess indoor and outdoor conditions of preschool children in a free-living environment.

Architectural design and physical activity: an observational study of staircase and elevator use in different buildings.

BACKGROUND: The indoor built environment has the potential to influence levels of physical activity. However, the extent to which architectural design in commercial buildings can influence the percentage of people choosing to use the stairs versus elevators is unknown. The purpose of this study was to determine if buildings with centrally located, accessible, and aesthetically pleasing staircases result in a greater percentage of people taking the stairs. METHODS: Direct observations of stair and elevator use were conducted in 3 buildings on a university campus. One of the buildings had a bank of 4 centrally located elevators and a fire escape stairwell behind a steel door. The other 2 buildings had centrally located staircases and out-of-the-way elevators. RESULTS: The percentage of people who ascended the stairs was 8.1% in the elevator-centric building, compared with 72.8% and 81.1% in the 2 stair-centric buildings (P < .001). In addition, the percentage of people who descended the stairs was 10.8% in the first building, compared with 89.5% and 93.7% in the stair-centric buildings (P < .001). CONCLUSIONS: The results of the current study suggest that if buildings are constructed with centrally located, accessible, and aesthetically pleasing staircases, a greater percentage of people will choose to take the stairs.