Training-induced Increase in Bone Mineral Density between Growing Male and Female Rats

Area of Science:

• Exercise Physiology
• Bone Biology
• Animal Models

Background:

• Bone mineral density (BMD) and bone strength are critical for skeletal health.
• Resistance training is known to positively influence bone properties.
• Understanding sex-specific responses to training during growth is important for optimizing skeletal development.

Purpose of the Study:

• To investigate potential sex differences in bone mineral density (BMD) and bone strength (Fmax) following resistance training in growing rats.
• To determine if resistance training elicits similar bone adaptations in male and female rats during the growth period.

Main Methods:

• 16 male and 16 female rats (approx. 8 weeks old) were divided into sedentary control and resistance-trained (RT) groups.
• RT groups performed a vertical ladder climbing exercise with tail weights 3 times per week for 6 weeks.
• Tibial bone mineral density and maximum force (Fmax) were measured post-intervention.

Main Results:

• No significant interaction effects between sex and exercise were observed for BMD or Fmax.
• While males exhibited higher absolute Fmax, both sexes showed significant increases in BMD and Fmax with resistance training compared to controls.
• No sex differences were found in the training-induced elevation of BMD and bone mechanical properties.

Conclusions:

• Resistance training effectively enhances bone mineral density and bone strength in growing rats.
• The positive effects of resistance training on bone properties during growth are comparable between male and female rats.
• These findings suggest that resistance exercise is a valuable intervention for promoting skeletal health in both sexes during development.