Objectives The potential effects of physical activity and sedentary time on children’s increasing neck and shoulder pain are unclear. The aim of this cross-sectional study was to evaluate the associations between objectively measured physical activity or sedentary time and neck and shoulder pain in children.

Methods Children (n=905; 10–15 years old) filled in an electronic questionnaire during school hours on the frequency of their neck and shoulder pain. Daytime moderate to vigorous physical activity and sedentary time were measured objectively with an ActiGraph accelerometer. A multinomial logistic regression was applied to study the associations. The results were adjusted for age, gender, body mass index and bedtime.

Results Neck and shoulder pain experienced at least once a week was reported by 26.1% of children. A higher proportion of boys (45.9%) than girls (24.2%) achieved at least 60 min of moderate to vigorous physical activity/day (p<0.001). Girls were more sedentary than boys (sedentary time 66.4 vs. 63.1%) (p<0.001). Higher moderate to vigorous physical activity time was associated with a lower probability of experiencing neck and shoulder pain among boys, but not among girls. No association was found between sedentary time and neck and shoulder pain.

Conclusions A quarter of the girls and boys reported frequent neck and shoulder pain. Boys achieved more moderate to vigorous physical activity than girls and higher moderate to vigorous physical activity was associated with a lower probability of having neck and shoulder pain, but only in boys. Neck and shoulder pain is the most common musculoskeletal pain and its prevalence is increasing. Preventing childhood pain is important, as neck and shoulder pain causes restrictions in daily living and is persistent to adulthood. Our study showed, that boys with more moderate to vigorous physical activity, had less weekly neck and shoulder pain symptoms. The present results are an addition to the list of benefits of physical activity and are valuable to, for example, healthcare personnel and teachers, who guide and teach children and adolescents. Families can benefit from new knowledge when considering supportive parenting activities. Municipalities can use the new information to design services for children or families.