Food consumption and body composition in mice selected for high wheel-running activity

Area of Science:

• Animal behavior genetics
• Exercise physiology
• Obesity research

Background:

• Genetic selection can alter physiological traits.
• Wheel running is a model for voluntary physical activity.
• Understanding factors influencing food intake and body composition is crucial for metabolic health.

Purpose of the Study:

• To investigate the impact of genetic selection for high wheel running on food consumption and body composition in mice.
• To determine the effects of prolonged access to running wheels on these parameters.
• To explore potential interactions between genetic predisposition and exercise on metabolic outcomes.

Main Methods:

• Utilized 13th-generation mice selected for high wheel-running activity and control lines.
• Assigned mice to either active (wheel access) or sedentary (wheel locked) conditions for 8 weeks.
• Measured food consumption through feeding trials and body composition using hydrogen isotope dilution.

Main Results:

• Selected mice and active mice consumed more food than control and sedentary mice, respectively.
• Selected mice exhibited lower total body fat (24.5% reduction) compared to control mice.
• Active mice showed a significant reduction in body fat (29.2%) compared to sedentary mice.
• No significant differences in lean body mass were observed between groups.

Conclusions:

• Genetic selection for high wheel running influences food intake and reduces body fat.
• Voluntary wheel running independently reduces body fat.
• Reduced adiposity, not altered lean mass, explains the lower body mass in selected mice.