Bone response to jumping is site-specific in children: a randomized trial

Area of Science:

• Pediatric Bone Health
• Skeletal Loading and Growth
• Exercise Physiology in Children

Background:

• Childhood bone mass accrual is critical for lifelong skeletal health.
• Skeletal loading during growth is a key factor in optimizing bone mineral acquisition.
• Understanding the impact of physical activity on pediatric bone density is essential.

Purpose of the Study:

• To investigate the effect of a structured jumping program on bone mineral content (BMC) and volumetric bone density in children.
• To determine if the pubertal stage influences the bone's response to skeletal loading from jumping.
• To compare bone outcomes between children participating in a jumping program and a control group.

Main Methods:

• Randomized controlled trial involving 54 children aged 3-18 years.
• Intervention group performed 25 jumps daily from a 45-cm box, 5 days/week for 12 weeks.
• Bone mineral content (BMC) and volumetric bone density were measured using dual-energy x-ray absorptiometry and peripheral quantitative computed tomography.

Main Results:

• Children in the jumping program showed significantly greater increases in total body BMC and leg BMC compared to the control group.
• The positive effect of jumping on bone density varied by pubertal stage, with the greatest benefits observed in pubertal children.
• No significant bone benefit was observed at the distal tibia in peripubertal children, a period of rapid growth.

Conclusions:

• Skeletal loading through jumping effectively increases bone mineral content in the total body and legs of children across different pubertal stages.
• The efficacy of jumping interventions for bone health may be influenced by the child's pubertal development stage.
• Jumping may not enhance bone density at trabecular bone sites during rapid growth periods like the peripubertal stage.