The Effects of a Physical Education Intervention Program on the Bone Properties of Second- and Third-Grade Pupils: A Cluster Randomized Controlled Trial

Abstract

Background: Many young children do not participate in sufficient physical activity for promoting optimal bone growth. The objective of this study was to investigate the effect of young children who participated in a school-based intervention program on bone properties. The program included structured physical activity, with a focus on the application of mechanical loads on the upper and lower limbs. Methods: A cluster randomized controlled trial was conducted, in which classes were randomly assigned to the intervention or control groups. A total of 295 (50.17% girls) children from the second and third grades from 12 classes in Israel were randomly allocated to an intervention consisting of three 10-minute weekly medium- to high-intensity activities throughout one academic year or to a treatment as usual control group. Bone properties were measured at the distal radius and tibia shaft using speed of sound, before and after the intervention. Results: Distal radius properties improved significantly for both boys and girls in the intervention group (boys: meanpre = 3769.95, meanpost = 3875.08, Δ = 2.80%; girls: meanpre = 3766.27, meanpost = 3890.83, Δ = 3.30%; d = 1.03); whereas, tibia shaft properties only significantly improved for boys (meanpre = 3663.98, meanpost = 3732.75, Δ = 1.90%; d = 1). Conclusions: These findings indicate that distal radius properties of children can be positively affected by a short, easy to implement intervention program that does not require special resources.

Effects of Early-Childhood-Based Interventions Influencing Bones: A Systematic Review

“…From the 12 included articles, eight obtained an excellent methodological quality score [ 25 , 26 , 28 , 30 , 32 , 35 , 36 ], while the remaining four studies obtained a good methodological quality score [ 27 , 29 , 33 , 34 ]. None of the included studies had fair or poor methodological quality.…”

“…From them, only two dealt with subjects about pubertal age (13–17 years) [ 35 , 36 ], while the remaining 10 articles analyzed subjects in both prepubertal and early pubertal stages (6–12 years) [ 25 , 30 , 31 , 32 , 33 , 34 ]. In addition, it is worth noting the wide variety of countries that integrated this type of study, such as the USA [ 27 , 29 ], Switzerland [ 25 , 33 , 34 ], Israel [ 28 ], Canada [ 31 , 32 ], Denmark [ 30 ], and Australia [ 35 , 36 ].…”

“…Assessment tools: Dual-energy X-ray absorptiometry (DXA) was used [ 25 , 26 , 27 , 29 , 30 , 32 , 33 , 34 , 35 , 36 ], followed by ultrasound densitometer [ 28 , 35 , 36 ] and peripheral quantitative computed tomography (pQCT) [ 26 , 31 ].…”

“…Intervention protocols: Six articles carried out intervention programs based on plyometric exercises (mainly high-intensity training that involves explosive movements based on the Stretch-Shortening Cycle (SSC)). This cycle enhances the power of the subsequent movement [ 25 , 27 , 30 , 32 , 35 , 36 ], while the rest of the studies purposed other methodologies: the implementation of varied high-intensity activities in 10-min time periods [ 28 , 31 , 33 , 34 ] and sports practices [ 26 , 29 , 30 ].…”

“…Outcomes: Regarding the results for bone parameters, 10 out of 12 studies detected significant improvements in the intervention groups compared to their respective control groups [ 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ].…”