# Associations between physical activity, fitness, cognitive and academic performance in Swedish adolescents: Findings from a cross-sectional study

## TL;DR

This study finds weak links between fitness and academic performance in Swedish teens, with lower fitness and grades among those with less-educated or foreign-born parents.

## Contribution

The study is novel in examining how fitness mediates academic performance and highlights disparities in fitness and grades among specific demographic groups.

## Key findings

- Cardiovascular fitness weakly correlates with math and language grades in adolescents.
- Cognitive performance mediates 40% of the link between fitness and academic grades.
- Adolescents with less-educated or foreign-born parents show lower fitness and academic performance.

## Abstract

Adolescence is a crucial phase for the development of cognitive abilities linked to academic performance. Factors such as physical activity (PA) and fitness have been hypothesized to be linked to these outcomes, although the evidence is inconclusive. This study aimed to examine the associations between PA, fitness, academic, and cognitive performance in the same sample of adolescents.

In this cross-sectional study, 1139 Swedish adolescents (mean age 13.4 years) participated. We assessed PA (accelerometry), cardiovascular fitness (submaximal ergometer test), cognitive performance (computer-based test assessing episodic and working memory with 3 tests per domain), and academic performance (grades in math and language, Swedish). We utilized multilevel mixed models to explore associations and structural equation modeling to perform mediation analyses.

We found a weak positive association between cardiovascular fitness and math grades (b: 0.18, 95% CI: 0.09, 0.26 β: 0.18), language grades (b: 0.16, 95% CI: 0.07, 0.25 β: 0.13), and cognitive performance (b: 0.01, 95% CI: 0.00, 0.02 β: 0.11). Further, cognitive performance scores mediated 40% of the associations between fitness and math, and language grades. Adolescents with parents with short education (≤12 years of education) or foreign-born had lower fitness levels and grades in math and language (all p < 0.05).

Fitness was the only significant factor associated with cognitive and academic performance, although the association was weak. Given our findings of low fitness and academic performance among adolescents with parents with short education or parents born abroad, future studies should tailor their interventions to ensure the inclusion of these groups.