The presentation of unhealthy psychological symptoms are rising sharply in adolescents. Detrimental lifestyle behaviours are proposed as both possible causes and consequences. This study set out to compare selected measures of quality and quantity of movement between adolescents with and without unhealthy psychological symptoms. Using a cross sectional design, 96 participants completed the study from a whole year group of 166, age (13.36 ± 0.48) male 50.6% from a secondary school in Oxfordshire, England as a part of a larger study (EPIC) between January and April 2018. Measures were taken of quality and quantity of movement: reaction/movement time, gait pattern & physical activity, alongside psychological symptoms. Differences in movement behaviour in relation to psychological symptom and emotional problem presentation were determined using ANOVA. In the event of a significant result for the main factor of each parameter, a Bonferroni -corrected post hoc test was conducted to show the difference between categories in each group. Results for both unhealthy psychological symptoms and emotional problems were grouped into four categories (‘Close to average’, ‘slightly raised’, ‘high’ and ‘very high’). Early adolescents with very high unhealthy psychological symptoms had 16.79% slower reaction times (p = 0.003, η_p² = 0.170), 13.43% smaller walk ratio (p = 0.007, η_p² = 0.152), 7.13% faster cadence (p = 0.005, η_p² = 0.149), 6.95% less step time (p = 0.007, η_p² = 0.153) and 1.4% less vigorous physical activity (p = 0.04, η_p² = 0.102) than children with close to average psychological symptoms. Early adolescents with very high emotional problems had 12.25% slower reaction times (p = 0.05, η_p² = 0.081), 10.61% smaller walk ratio (p = 0.02, η_p² = 0.108), 6.03% faster cadence (p = 0.01, ηp² = 0.134), 6.07% shorter step time (p = 0.007, ηp² = 0.141) and 1.78% less vigorous physical activity (p = 0.009, ηp² = 0.136) than children with close to average emotional problems. Different movement quality and quantity of was present in adolescents with unhealthy psychological symptoms and emotional problems. We propose movement may be used to both monitor symptoms, and as a novel therapeutic behavioural approach. Further studies are required to confirm our findings.

• Early adolescents with psychological symptoms have slower movement behaviour compared with other early adolescents

• Quality and quantity of Movement as measured by reaction time, gait or physical activity may be used to monitor psychological symptoms

• Focusing in quality and quantity of movement may be a novel therapeutic target for improving psychological symptoms in early adolescents.