<
h4 class=""
h4"">Background context
h4>Reduced vertebral strengt
h is a clear risk factor for vertebral fractures. Men and women wit
h vertebral fractures often
have reduced vertebral size and bone mineral density (BMD). Vertebral strengt
h is controlled by bot
h genetic and developmental factors. Malnutrition and low levels of p
hysical activity are commonly considered to result in reduced bone size during growt
h. Several studies
have also demonstrated t
he general relations
hip between BMD and p
hysical activity in t
he appendicular skeleton.<
h4 class=""
h4"">Purpose
h4>
In this study, we wanted to clarify the role of physical activity on vertebral bodies. Vertebral dimensions appear to generally be less pliant than long bones when lifetime changes occur. We wanted to explore the association between physical activity during late adolescence and vertebral strength parameters such as cross-sectional size and BMD.<h4 class=""h4"">Study designh4>
The association between physical activity and vertebral strength was explored by measuring vertebral strength parameters and defining the level of physical activity during adolescence.<h4 class=""h4"">Patient sampleh4>
The study population consisted of 6,928 males and females who, at 15 to 16 and 19 years of age, responded to a mailed questionnaire inquiring about their physical activity. A total of 558 individuals at the mean age of 21 years underwent magnetic resonance imaging (MRI) scans.<h4 class=""h4"">Methodsh4>
We measured the dimensions of the fourth lumbar vertebra from the MRI scans of the Northern Finland Birth Cohort 1986 and performed T2* relaxation time mapping, reflective of BMD. Vertebral strength was based on these two parameters. We analyzed the association of physical activity on vertebral strength using the analysis of variance.<h4 class=""h4"">Results and conclusionsh4>
We observed no association between the level of physical activity during late adolescence and vertebral strength at 21 years.