Fitness and Screen Time at Age 13 Relates to Academic Performance at Age 16

Investigate the longitudinal relationship between physical activity, organised physical activity, fitness, screen time and academic performance among Swedish adolescents.

Data from 1139 adolescents at age 13, included vigorous physical activity (accelerometry), fitness (submaximal ergometer test), screen time and organised physical activity participation (self-reported) and academic performance (math and Swedish grades at ages 13 and 16 from registry). Academic performance at age 16 was categorised as A-D (higher grades or pass) or E, F (fail or at-risk of failing). Multilevel logistic regression models were used to examine the relationships while adjusting for gender, parental education, parental country of birth and academic performance at age 13.

Higher fitness at age 13 was associated with increased odds of receiving A-D at age 16 (OR: 1.04 per mL, 99% CI 1.00, 1.07, p = 0.003). High screen time during weekdays was associated with reduced odds (OR: 0.40, 99% CI 0.20, 0.81, p = 0.001) compared to low screen time.

Academic performance at the end of compulsory school (age 16) was related to fitness and screen time 3 years earlier. These findings create a paradigm for future randomised controlled trials to explore how influencing these factors might affect academic performance.