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Published on: January 29, 2018
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Association between sedentary behavior and bone mass in adolescents.
A Pelegrini1, J A Klen2, A M Costa2
1State University of Santa Catarina (UDESC), Florianópolis, Santa Catarina, Brazil. andreia.pelegrini@udesc.br.
Summary
Sedentary behavior, particularly internet use for non-school purposes, is linked to higher bone mineral density (BMD) and content (BMC) in adolescents. However, excessive computer time may negatively impact bone health in normal-weight youth.
Area of Science:
- Pediatric Bone Health
- Adolescent Health Behaviors
- Sedentary Lifestyle Research
Background:
- The impact of sedentary behavior on adolescent bone health remains debated.
- Some specific sedentary activities may not negatively affect bone health, even in normal-weight individuals.
Purpose of the Study:
- To investigate the association between various sedentary behaviors and bone mass in adolescents.
- To differentiate effects based on weight status (normal weight vs. overweight).
Main Methods:
- 104 adolescents (10-14 years) categorized by weight status.
- Sedentary behaviors assessed via questionnaire (internet, computer, TV, video games) and accelerometry.
- Bone mineral density (BMD) and bone mineral content (BMC) measured using X-ray absorptiometry.
Main Results:
- Internet use for non-school purposes positively correlated with total and lumbar BMD in all adolescents.
- Overweight adolescents showed a negative correlation between computer use and lumbar BMD.
- Internet use for non-school purposes positively correlated with total and lumbar BMC in overweight adolescents and lumbar BMC in normal-weight adolescents.
Conclusions:
- Increased sedentary time, especially non-school internet use, is associated with enhanced bone mineral density and content in adolescents.
- Excessive computer use may be detrimental to bone mineral density in normal-weight adolescents.
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