Daily Physical Education in the School Curriculum in Prepubertal Girls during 1 Year is Followed by an Increase in Bone Mineral Accrual and Bone Width—Data from the Prospective Controlled Malmö Pediatric Osteoporosis Prevention Study

Abstract

The aim of this study was to evaluate a general school-based one-year exercise intervention program in a population-based cohort of girl at Tanner stage I. Fifty-three girls aged 7 to 9 years were included. The school curriculum based exercise intervention program included 40 minutes per school day. Fifty healthy age-matched girls assigned to the general school curriculum of 60 minutes physical activity per week served as controls. Bone mineral content (BMC; g) and areal bone mineral density (aBMD; g/cm 2 ) were measured with dual X-ray absorptiometry (DXA) of the total body (TB), lumbar spine (L2-L4 vertebra), the third lumbar vertebra (L3), the femoral neck (FN) and the leg. Volumetric bone mineral density (vBMD; g/cm 3 ) and bone width were calculated at L3 and FN. Total lean body mass and total fat mass were estimated from the total body scan. No differences were at baseline found in age, anthropometrics or bone parameters when the groups were compared. The annual gain in BMC was in the cases 4.7 percentage points higher in lumbar spine and 9.5 percentage points higher in L3 than in the controls (both p<0.001). The annual gain in aBMD was in the cases 2.8 percentage points higher in lumbar spine and 3.1 percentage points higher in L3 than in the controls (both p<0.001). The annual gain in bone width was in the cases 2.9 percentage points higher in L3 than in the controls (p<0.001).A general school-based exercise program in 7 -9-year-old girls enhances the accrual of BMC and aBMD and increases bone width.

A 3-Year Physical Activity Intervention Program Increases the Gain in Bone Mineral and Bone Width in Prepubertal Girls but not Boys: The Prospective Copenhagen School Child Interventions Study (CoSCIS)

“…Several previous school based prospective intervention (training) studies have demonstrated that exercise induces positive skeletal effects in pre-pubertal girls (25)(26)(27). These trials have reported 1.5 -29 % greater bone mineral accrual in the intervention groups compared to controls.…”

“…For example, cross-sectional studies have reported higher BMD in physically active compared to physically inactive children (9-11) and a higher BMD in the dominant arm of both tennis and squash players compared with the non-dominant arm (12). Prospective controlled and uncontrolled exercise intervention studies in volunteers (13;14) and in school based exercise interventions, including pre-pubertal and early pubertal children, have reported a higher bone mineral acquisition in the intervention group than in the control group (15)(16)(17)(18)(19)(20). However, all but three (21-23) of these studies have modified the existing physical education curriculum and replaced this with specifically designed bone stimulating activities.…”

Does Exercise Influence Pediatric Bone? A Systematic Review

“…1 The flowchart shows the numbers of articles initially identified and exclusion and inclusion steps. * Randomization unit: I = individual, S = school or class; D = change; These studies provided different data from the same study: Löfgren et al [31] was used for female and male total body, femoral neck, and spine BMC; Linden et al [29] was used for male femoral neck BMD; Valdimarsson et al [50] was used for female spine and femoral neck BMD; NS = not stated; DPA = dual photon absorptiometry, DXA=dual energy x-ray absorptiometry; pQCT = peripheral quantitative computed tomography; BMC = bone mineral content; BA = bone area; aBMD = areal bone mineral density; PHV = peak height velocity; PF = proximal femur; LS = lumbar spine; FN = femoral neck; TB = total body; FA = forearm; TR = trochanter; PC = periosteal circumference; EC = endosteal circumference; Ar = area; CortAr = cortical area; CortThk = cortical thickness; Cort = cortical; Tot = total; vBMD = volumetric bone mineral density; MSCA = muscle crosssectional area; AS!BC = Action Schools! British Columbia.…”

Relationship between total and segmental bone mineral density and different domains of physical activity among children and adolescents: cross-sectional study

“…3,4 PA exerts significant influence on BMD accrual during growth, 4 which can be categorized into domains (school, leisure and sports). School PA denotes activities performed during school activities, 5,6 while leisure PA denotes activities performed during free time. [7][8][9] Moreover, in young populations, sport PA can itself be considered to be a PA domain.…”