Background: Background: Latina adolescents report low levels of moderate-vigorous physical activity (MVPA) and high lifetime risk of lifestyle-related diseases. There is a lack of MVPA interventions targeted at this demographic despite documented health disparities. Given their high rates of using mobile technology, interventions delivered through mobile devices may be effective for this population. Objective: Objective: The current paper examines efficacy of the Chicas Fuertes intervention in increasing MVPA across six months in Latina adolescents. Methods: Methods: Participants were Latina adolescents (ages 13-18) in San Diego County who reported being underactive (<150 minutes/week of MVPA). All participants received a wearable fitness tracker (Fitbit Inspire HR); half were randomly assigned to also receive the multimedia intervention. Intervention components included a personally tailored website, personalized texting based on Fitbit data, and social media. The primary outcome was change in minutes of weekly MVPA from baseline to six months (6m), measured by ActiGraph accelerometers and the 7-Day Physical Activity Recall Interview. Changes in daily steps using Fitbit devices were also examined to test intervention efficacy. Results: Results: Participants (N=160) were 15.3 years old on average, and mostly second generation in the U.S. For ActiGraph-measured MVPA, participants in the Intervention group (N=83) increased from a median of 0 min/week at baseline (IQR 26) to 64 min/week at 6m (IQR 28) compared to Control participants, who showed increases from a median of 0 at baseline (IQR 24) to 41 min/week at 6m (IQR 21) (P=.04). Self-reported MVPA increased in the Intervention group from a median of 119 min/week at baseline (IQR 122.5) to 147 min/week at 6m (IQR 85) compared to Control participants, who showed increases from a median of 120 (IQR 186.25) at baseline to 124 min/week at 6m (IQR 69) (P=.03). Steps also increased in both groups, with the Intervention group showing significantly greater increases (P=.03). Conclusions: Conclusions: This intervention was successful in using a tailored technology-based strategy to increase MVPA in Latina adolescents and provides a promising approach for addressing a key health behavior. Given the scalable technology used, future studies should focus on broad scale dissemination to address health disparities. Clinical Trial: ClinicalTrials.gov NCT04190225; https://clinicaltrials.gov/study/NCT04190225?id=NCT04190225

Are experiences that bring meaning different from experiences that bring happiness? If so, do people seek out different experiences in pursuing meaning versus happiness? In an adversarial collaboration, we conducted three preregistered experiments (total N = 879) to address these questions. We asked participants to describe an experience from the past month (Study 1) or past day (Study 2) that had provided them with either happiness, meaning, happiness without meaning, or meaning without happiness. Experiences that were happy but not meaningful differed substantially from those that were meaningful but not happy. However, experiences that provided happiness showed only small differences from those that provided meaning. In Study 3, to examine whether people seek out different experiences in pursuing happiness versus meaning, we instructed participants to choose an activity over the weekend that would provide them with happiness, meaning, happiness without meaning, or meaning without happiness. Again, experiences differed substantially when people pursued happiness without meaning or meaning without happiness, but these differences disappeared when people were simply told to pursue happiness or meaning. Our findings suggest that happiness and meaning are linked to distinct sets of thoughts, feelings and behaviors, but the differences between them are small in everyday life.

In this study, we investigated the extent to which adolescents who spend time playing violent video games exhibit higher levels of aggressive behaviour when compared with those who do not. A large sample of British adolescent participants (n = 1004) aged 14 and 15 years and an equal number of their carers were interviewed. Young people provided reports of their recent gaming experiences. Further, the violent contents of these games were coded using official EU and US ratings, and carers provided evaluations of their adolescents' aggressive behaviours in the past month. Following a preregistered analysis plan, multiple regression analyses tested the hypothesis that recent violent game play is linearly and positively related to carer assessments of aggressive behaviour. Results did not support this prediction, nor did they support the idea that the relationship between these factors follows a nonlinear parabolic function. There was no evidence for a critical tipping point relating violent game engagement to aggressive behaviour. Sensitivity and exploratory analyses indicated these null effects extended across multiple operationalizations of violent game engagement and when the focus was on another behavioural outcome, namely, prosocial behaviour. The discussion presents an interpretation of this pattern of effects in terms of both the ongoing scientific and policy debates around violent video games, and emerging standards for robust evidence-based policy concerning young people's technology use.