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Updated: Jul 11, 2026
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Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts
Published on: January 29, 2018
Resistance training and bone mineral density during growth
M Z Smith1, B M Goettsch, R D Van Ramshorst
1Department of Biological Sciences, Chapman University, Orange, CA 92866, USA.
International Journal of Sports Medicine
|September 21, 2007
Summary
Heavier weight, fewer repetitions resistance training significantly increased bone mineral density in rats. Lighter weight, more repetitions also boosted bone modeling markers but not bone density.
Area of Science:
- Exercise Physiology
- Bone Biology
- Biomechanical Engineering
Background:
- Resistance training is crucial for skeletal health.
- Understanding optimal training parameters for bone development is essential.
- Bone modeling and bone mineral density (BMD) are key indicators of skeletal maturity and strength.
Purpose of the Study:
- To compare the effects of high-intensity (HI) versus low-intensity (LI) resistance training on bone modeling and BMD in maturating rats.
- To determine if equivalent training volumes of different intensities yield similar bone adaptation.
- To investigate the osteogenic response to distinct resistance training protocols.
Main Methods:
- Twenty-three male rats were divided into control, LI, and HI groups.
- LI and HI groups underwent 6 weeks of vertical ladder climbing with appended weights.
- Training protocols were designed with equivalent total work volumes but different weight/repetition schemes.
Main Results:
- Serum osteocalcin (OC), a bone formation marker, was significantly elevated in both HI and LI groups compared to controls.
- High-intensity (HI) resistance training led to a significant increase in tibial bone mineral density (BMD) compared to both LI and control groups.
- Low-intensity (LI) training did not result in a significant difference in BMD compared to the control group.
Conclusions:
- Both high-intensity (HI) and low-intensity (LI) resistance training stimulate bone modeling, as indicated by increased serum osteocalcin.
- Only high-intensity (HI) resistance training, characterized by heavier weights and fewer repetitions, significantly enhances bone mineral density in maturating rats.
- Training intensity, not just volume, plays a critical role in achieving significant bone mineral density gains through resistance exercise.
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