# Screen Time, Fatigue, Obesity and Physical Inactivity: Health Correlates of Problematic Smartphone Use in Adolescents

## TL;DR

Problematic smartphone use in Tunisian adolescents is linked to inactivity, fatigue, and obesity, with sports offering protection, especially for girls.

## Contribution

This study identifies PSU as a public health concern and highlights sex-specific protective effects of sports participation.

## Key findings

- PSU prevalence was 15.7%, higher in males and mid-adolescents.
- Sports participation showed protective effects against PSU, particularly in females.
- PSU was associated with increased screen time, reduced physical activity, higher BMI, and more fatigue.

## Abstract

This study aimed to determine the prevalence of problematic smartphone use (PSU) among Tunisian adolescents, examine variations by sex and age and investigate associations with physical activity, fatigue and obesity while assessing the potential protective role of sports participation.

A cross‐sectional study of 960 adolescents (53% female), aged 14–16 years utilized validated Arabic instruments including the Smartphone Addiction Scale—Short Version (SAS‐SV), International Physical Activity Questionnaire (IPAQ‐SF) and Fatigue Assessment Scale (FAS). Anthropometric measurements followed WHO protocols, and objective screen time data were collected from device tracking features. Statistical analyses included Mann–Whitney U tests, chi‐square tests, Spearman's correlations and logistic regression models with sex stratification, all adjusted for multiple comparisons using Benjamini–Hochberg correction.

PSU prevalence was 15.7%, with significantly higher rates in males (p < 0.001) and during mid‐adolescence (p < 0.001). Adolescents with PSU showed substantially higher screen time (435 vs. 155 min/day, p < 0.001), reduced vigorous physical activity (0 vs. 480 MET‐min/week, p < 0.001), increased obesity (12.6% vs. 0.7%, p < 0.001) and more severe fatigue (50.3% vs. 5.8%, p < 0.001). Sports participation demonstrated protective effects against PSU (OR = 0.4–0.6), with significantly stronger effects in females (interaction p = 0.03).

PSU represents a significant public health concern among Tunisian adolescents, with a prevalence of 15.7% that is higher in males and mid‐adolescents. It is associated with excessive screen time, inactivity, elevated BMI and fatigue, whereas sports participation offers a protective effect, particularly among girls.

Problematic smartphone use (PSU) affects one in six adolescents and clusters with physical inactivity, fatigue and higher BMI, making it a relevant public health issue for schools and primary care.PSU is closely linked to excessive screen time and low physical activity, supporting prevention approaches that promote active alternatives rather than screen restriction alone.Sports participation is a clear protective factor against PSU, obesity and severe fatigue, indicating its value as a practical and scalable intervention.Sex differences are clinically and policy relevant, with stronger risk associations in males and stronger protective effects of sports in females.Longitudinal and intervention studies are needed to clarify causal pathways and guide effective prevention strategies using objective screen‐time measures.

Problematic smartphone use (PSU) affects one in six adolescents and clusters with physical inactivity, fatigue and higher BMI, making it a relevant public health issue for schools and primary care.

PSU is closely linked to excessive screen time and low physical activity, supporting prevention approaches that promote active alternatives rather than screen restriction alone.

Sports participation is a clear protective factor against PSU, obesity and severe fatigue, indicating its value as a practical and scalable intervention.

Sex differences are clinically and policy relevant, with stronger risk associations in males and stronger protective effects of sports in females.

Longitudinal and intervention studies are needed to clarify causal pathways and guide effective prevention strategies using objective screen‐time measures.