Abstract
Background
There is concern that a sedentary lifestyle in childhood is harmful to spinal health. The literature stands divided, as there are reports also of an increased injury rate in children who are physically active. Children cannot be expected to remember correctly amount of physical activity in the past nor can they remember correctly past events of backpain. We therefore used a new method, SMS-Track, to collect weekly data over a long period of time.
Methods and material
In a prospective Danish study, the effect of increased physical activity was tested vs. “business-as-usual” in 10 primary schools. We collected data on time spent on physical activities and any backpain in the preceding week. For this we sent the children weekly text-messages, to which the children/parents responded with a text-message as well. If the child reported having had any backpain during the preceding week, the parents were contacted, the child seen by a health professional, and treatment initiated if necessary.
Results
Compliance for responding to the text-messages was 92%. The total risk time was 35,238 weeks for the participating 1208 children. As the assumption for proportional hazards was not met, negative binomial regression was used to test the association between level of physical activity and incidence of backpain. In addition, we adjusted for age, school and grade level and used robust standard errors. Adjustment for clustering in the school classes was also made.
Sport participation reduced the incidence rate significantly with 0.08 for each day with organised sport after school.
Conclusion
These interim analyses indicate that sport participation is protective, reducing the risk of reporting backpain in childhood.
Conflict of interest: None
Sources of funding: The project was funded by: Kiropraktor Fonden, Team Danmark, Nordea Foundation, The IMK-foundation, Østifterne, Brd. Hartmanns fond, Svendborg Kommune, University of Southern Denmark and University College Lillebælt.
