Relationship between the practice of physical activity and quality of movement in adolescents: a screening tool using self-organizing maps.

OBJECTIVES: The aim of this study was to determine whether the most physically active adolescents have better lower limb control.
METHODS: 31 high school students (12 males and 19 females) participated in this study. The Anterior Knee Pain Scale was used to find any cases of knee pain. Only subjects with high scores were selected, to exclude those with knee pain or lower limb injuries. Single Leg Squat and Tuck Jump Assessment were used to evaluate movements with two cameras in a two-dimensional assessment. The IPAQ Questionnaire was used to score the physical activity and to classify it into MET total, MET moderate activity, MET vigorous activity and MET walking. These scores were related to knee angle at landing, age and body mass index by self-organizing maps analysis.
RESULTS: The subjects were classified into 4 clusters and the descriptive statistics of the different clusters were determined to find any differences. The subjects in cluster 3 were classified as those with the highest risk factors of suffering lower limb musculoskeletal disorders or knee pain, even though injuries do not only depend on quality of movement. Physical activity was not related to healthy movements during jump and single leg squat.
CONCLUSION: Physical activity alone cannot be an indicator of good quality lower limb movement, as the knee valgus angle plays a determining role, as it could also depend on neuromuscular control and anatomical characteristics. The analytical method described in the study could be used by physical education teachers to detect potential risk factors for musculoskeletal problems in the lower limbs, especially in the knees.