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Lifelong sedentary behaviour and femur structure.
H Fonseca1, D Gonçalves, P Figueiredo
1FADEUP, Biochemistry, Porto, Portugal. helder.rmf@gmail.com
International Journal of Sports Medicine
|March 8, 2011
Summary
Lifelong physical activity in mice improved femur structure, maintaining bone quality and osteocyte number. Sedentary behavior exacerbated age-related bone loss, highlighting activity
Area of Science:
- Bone biology
- Gerontology
- Exercise physiology
Background:
- Aging is associated with decreased bone quality.
- The role of lifelong physical activity in mitigating age-related bone changes is not fully understood.
- Sedentary behavior may accelerate bone degeneration.
Purpose of the Study:
- To investigate the lifelong effects of physical activity on femur structure in mice.
- To compare bone microarchitecture in physically active, sedentary, and young mice.
- To determine if physical activity can prevent age-related bone loss.
Main Methods:
- Male C57BL/6 mice (n=30) were divided into three groups: lifelong wheel running (AA), sedentary (AS), and young controls (Y).
- Animals were housed for 23 months (AA and AS groups).
- Femur structure was analyzed using histomorphometry.
Main Results:
- Significant microarchitectural differences were found between young and aged mice, and between active and sedentary aged mice.
- Physically active mice (AA) showed higher cancellous bone surface (Cn.BS), trabecular number (Tb.N), and lower trabecular separation (Tb.Sp) compared to sedentary mice (AS).
- Osteocyte number (N.Ot) decreased in sedentary mice (AS) but not in active mice (AA) compared to young controls (Y), indicating age alone did not cause N.Ot reduction.
Conclusions:
- Reduced bone quality in aging is influenced by both age and physical activity levels.
- Lifelong physical activity preserves bone structure and quality, counteracting age-related decline.
- Sedentary behavior significantly worsens age-related bone differences, emphasizing the importance of exercise for bone health in aging individuals.
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