Weight-related Self-monitoring App Use Among Emerging Adults is Cross-sectionally Associated With Amount and Type of Physical Activity and Screen Time.

Weight-related self-monitoring (WRSM) apps are often used by emerging adults to assist in behavior change. However, little is known about the relationship between WRSM among the general population of emerging adults and various physical activity and screen time behaviors. This paper examines associations between WRSM app use and various forms of physical activity and screen time among a population-based sample of emerging adults. Data come from EAT 2018 (N = 1,568, mean age = 22.0 ± 2.0 years), a population-based sample of emerging adults from Minneapolis/St. Paul, Minnesota. Participants reported on the types of WRSM apps used (physical activity and/or dietary focused), in addition to how much time they spent doing physical activity, whether they practiced yoga, compulsive exercise, recreational screen time, social media use, and whether they viewed dieting/weight loss materials. Linear and logistic regressions were used to assess adjusted means and prevalences of outcomes. We found that physical activity-focused WRSM app users engaged in more hours of total (8.7 vs 7.2, P < .001), and moderate-to-vigorous (5.1 vs 4.3, P = .002) physical activity compared to non-users. Similar results were found for dietary WRSM app users compared to non-users. However, WRSM app users had higher levels of compulsive exercise and were more likely to view dieting/weight loss materials (Ps < .001). Findings suggest that although physical activity is higher among WRSM users, the types of physical activity and screen time behaviors WRSM users are engaging in may be harmful.

Using apps to self-monitor diet and physical activity is linked to greater use of disordered eating behaviors among emerging adults.

Use of weight-related self-monitoring (WRSM) apps is common among emerging adults, as are weight and shape concerns. The present study aimed to examine (1) whether emerging adult use of dietary-focused (e.g., MyFitnessPal) and physical activity-focused (e.g., Fitbit) WRSM apps was associated with weight-control and muscle-building behaviors, including commonly recommended/conventional behaviors and disordered behaviors and (2) whether prior use of weight-control and muscle-building behaviors in adolescence might explain such relationships. Data were collected as part of the EAT (Eating and Activity over Time) 2010-2018 study (n = 1446) and analyzed using gender-stratified logistic regression models adjusted for demographic characteristics and body mass index. Among women and men, physical activity- and dietary-focused app use were associated with greater adjusted prevalence of disordered weight-control behaviors (e.g., fasting, purging), and disordered muscle-building behaviors (e.g., using steroids). Physical activity- and dietary-focused app use were also associated with a higher adjusted prevalence of commonly recommended weight-control and conventional muscle-building behaviors (e.g., exercising, changing eating habits), but only among those who were also engaging in disordered behaviors. The observed associations remained statistically significant in models that further adjusted for adolescent use of the respective behaviors. Findings suggest that emerging adults who use physical activity- and dietary-focused WRSM apps are more likely to engage in disordered weight-control and muscle-building behaviors and that associations are not explained by engagement in these behaviors during adolescence. Future research is needed to examine if there are aspects of WRSM apps that could be modified to reduce potential harm.

Stay-at-Home Orders during COVID-19: The Influence on Physical Activity and Recreational Screen Time Change among Diverse Emerging Adults and Future Implications for Health Promotion and the Prevention of Widening Health Disparities.

BACKGROUND: The purpose of this study was to examine changes in physical activity (PA) and recreational screen time (RST) behaviors from pre-COVID-19 in 2018 to Spring 2020 during the mandatory stay-at-home order in an ethnically/racially, socioeconomically diverse sample of emerging adults. METHODS: Longitudinal data were analyzed from 218 participants (Mage = 24.6 ± 2.0 years) who completed two surveys: EAT 2018 (Eating and Activity over Time) and C-EAT in 2020 (during COVID-19). Repeated ANCOVAs and multiple linear regression models were conducted. RESULTS: Moderate-to-vigorous and total PA decreased (4.7 ± 0.3 to 3.5 ± 0.3 h/week [p < 0.001] and 7.9 ± 0.4 to 5.8 ± 0.4 h/week [p < 0.001], respectively), and RST increased from 26.5 ± 0.9 to 29.4 ± 0.8 h/week (p = 0.003). Perceived lack of neighborhood safety, ethnic/racial minoritized identities, and low socioeconomic status were significant predictors of lower PA and higher RST during COVID-19. For example, low SES was associated with 4.04 fewer hours of total PA compared to high SES (p < 0.001). CONCLUSIONS: Stay-at-home policies may have significantly influenced PA and RST levels in emerging adults with pre-existing disparities exacerbated during this mandatory period of sheltering-in-place. This suggests that the pandemic may have played a role in introducing or magnifying these disparities. Post-pandemic interventions will be needed to reverse trends in PA and RST, with a focus on improving neighborhood safety and meeting the needs of low socioeconomic and ethnic/racial minoritized groups.

Introducing Dietary Self-Monitoring to Undergraduate Women via a Calorie Counting App Has No Effect on Mental Health or Health Behaviors: Results From a Randomized Controlled Trial.

BACKGROUND: Strong positive relationships between dietary self-monitoring and eating disorder risk are seen in population-based, observational studies. However, current evidence cannot establish causality. Furthermore, little is known about other mental and behavioral health consequences of dietary self-monitoring among college women, a population vulnerable to eating disorders. OBJECTIVE: To determine if introducing dietary self-monitoring via a popular smartphone app to undergraduate women impacts eating disorder risk, other aspects of mental health, or health behaviors including dietary intake and physical activity. DESIGN: Randomized controlled trial. PARTICIPANTS/SETTING: Undergraduate women who had not engaged in dietary self-monitoring in the past year and who were at low-risk for an eating disorder participated between May and October 2019 (n = 200). INTERVENTION: Participants were randomly assigned to engage in dietary self-monitoring via MyFitnessPal for approximately 1 month or to receive no intervention. MAIN OUTCOME MEASURES: Self-report data on eating disorder risk, other mental health outcomes, and health behaviors were collected at baseline and post-intervention. STATISTICAL ANALYSES PERFORMED: Linear and logistic regressions were utilized to test hypotheses. RESULTS: Adherence to the intervention was high, with participants recording their dietary intake via MyFitnessPal on average 89.1% of days between baseline and post-intervention. Assignment to the intervention was not associated with changes in eating disorder risk, anxiety, depressive symptoms, body satisfaction, quality of life, nutritional intake, physical activity, screen time, or other forms of weight-related self-monitoring (all P > .05). CONCLUSIONS: Among dietary self-monitoring naive undergraduate women with low-risk of an eating disorder, dietary self-monitoring via MyFitnessPal for 1 month did not increase eating disorder risk, impact other aspects of mental health, or alter health behaviors including dietary intake. The null results in our study may be due to the selection of a low-risk sample; future research should explore whether there are populations for whom dietary self-monitoring is contraindicated.

Changes to Physical Activity during a Global Pandemic: A Mixed Methods Analysis among a Diverse Population-Based Sample of Emerging Adults in the U.S.

Emerging adults' lives have changed because of the COVID-19 pandemic. Physical activity (PA) behaviors need to be examined to inform interventions and improve health. Responses to the C-EAT (COVID-19 Eating and Activity over Time) survey (N = 720; age = 24.7 ± 2.0 yrs) were analyzed. This mixed-methods study quantitatively examined changes in self-reported PA (hours/week of mild PA, moderate-to-vigorous PA (MVPA), and total PA) from 2018 to 2020. Qualitative responses on how COVID-19 impacted PA were analyzed using a grounded theory approach. Hours of PA were lower on average for all intensity levels during COVID-19 than in 2018 (p's < 0.0001). Over half of the sample reported a decrease in MVPA (53.8%) and total PA (55.6%); 42.6% reported a decrease in mild PA. High SES were more likely to report an increase in total PA (p = 0.001) compared to those of lower SES. Most (83.6%) participants perceived that COVID-19 had influenced their PA. The most common explanations were decreased gym access, effects on outdoor PA, and increased dependence on at-home PA. Results suggest that emerging adults would benefit from behavioral interventions and health promotion efforts in response to the pandemic, with a focus on activities that can be easily performed in the home or in safe neighborhood spaces.

Cross-sectional associations between weight-related health behaviors and weight misperception among U.S. adolescents with overweight/obesity.

BACKGROUND: Weight misperception occurs when there is a discrepancy between one's actual and perceived weight status. Among adolescents with overweight/obesity, many believe that correcting weight misperception is imperative to inspire weight-related behavior change. However, past research has shown that adolescents with overweight/obesity who misperceive their weight status gain less weight over time compared to accurate perceivers. Therefore, our objective was to examine possible mechanisms underlying this relationship. Specifically, we examined the association between weight misperception and engagement in weight-related health behaviors among adolescents with overweight/obesity. METHODS: Self-reported data from the 2015 National Youth Risk Behavior Survey was used in analyses restricted to participants with overweight/obesity (n = 4383). Using multivariate logistic models correcting for sex, race/ethnicity, and grade in school, we examined the cross-sectional associations between weight misperception and engagement in weight-related health behaviors, specifically related to dietary intake, physical activity, and sleep. RESULTS: Adolescents with overweight/obesity who misperceived their weight status were more likely to drink 100% fruit juice two or more times per day (OR = 1.53, 95% CI: 1.20, 1.94), eat vegetables two or more times per day (OR = 1.29, 95% CI: 1.07, 1.57), be physically active for 1 hour or more per day for at least 5 days in the week prior (OR = 1.40, 95% CI: 1.15, 1.72), be on a sports team in the last year (OR = 1.55, 95% CI: 1.21, 1.97), sleep an average of at least 8 hours per school night (OR = 1.40, 95% CI: 1.15, 1.72), and less likely to be trying to lose weight (OR = 0.17, 95% CI: 0.15, 0.20). Misperceivers were more likely to consume breakfast every morning in the week prior and to drink a sports drink at least once per day, though these results were not statistically significant. We observed no difference in fruit intake, soda intake, or TV viewing between weight misperceivers and accurate perceivers. CONCLUSIONS: Overall, weight misperception among adolescents with overweight/obesity was associated with a number of beneficial weight-related health behaviors. Engagement in these healthy weight-related behaviors may explain some of the protective effect of weight misperception on weight gain over time. TRIAL REGISTRATION: Not applicable.