Developmental Patterns of Objectively Measured Motor Competence and Musculoskeletal Fitness among Finnish Adolescents

Purpose To examine how development of motor competence (locomotor, object control, stability) and development of musculoskeletal fitness (upper body and abdominal) are related during adolescence, in a large sample of Finnish youth over four years. Methods Study participants were students (n = 1147; 11.27[±0.33] years at baseline) attending public schools in Finland. Data were collected yearly (2017-2021). Motor competence was assessed using the throwing-catching combination test, 5-leaps test and side-to-side jumping test. Musculoskeletal fitness was assessed using the curl-ups and push-ups tests. To answer the research question, a parallel latent growth curve model was implemented. Covariates were sex, body mass index (BMI) and peak height velocity (PHV). Results Improvements in all motor competencies were positively associated with improvements in push-ups. Subsequently, improvements in 5-leaps and side-to-side jumping test scores were related to improvements in curl-ups. Our covariate results indicate sex (male), a healthy BMI, and undergoing PHV were associated with greater increases in motor competency and musculoskeletal fitness. Conclusions Given fitness has been shown to mediate the relationship between physical activity and motor competence, positive practices are needed to enhance adolescents’ experiences in physical activities and sports requiring adequate intensity, to improve fitness and motor competence.