Effects of resistance training on bone parameters in young and mature rats

1. Osteoporosis is a major public health problem that is predicted to worse n over the next decade and preventative strategies that increase bone stren gth have become the focus of substantial research. 2. Although mechanical load is a primary factor in the acquisition and main tenance of skeletal tissue, the type of exercise used and when in life it i s most effectively prescribed remain inconclusive. 3. The present study compared 10 weeks of resistance training in both young and mature female Sprague-Dawley rats and measured bone density and body c omposition by dual energy X-ray absorptiometry and biomechanical properties by three point bending tests of the tibia and femur. 4. No significant differences were observed for any of the bone parameters when comparing exercise and control groups at either age. This was despite using a comparable training protocol to that in humans and using loads of a pproximately 150% bodyweight. 5. The present study concludes that more intensive work programmes of resis tance training or different outcome measures are required when using animal models for skeletal research.