Temporal relationships between food acquisition and voluntary exercise in mice

Area of Science:

• Behavioral Neuroscience
• Animal Behavior
• Physiology

Background:

• Understanding the relationship between physical activity and energy intake is crucial for metabolic health.
• Operant conditioning models provide insights into motivated behaviors like food seeking and exercise.

Purpose of the Study:

• To investigate how voluntary wheel running (WR) affects food acquisition and activity patterns in mice.
• To examine sex differences in activity, food intake, and body weight regulation under varying food costs.

Main Methods:

• Mice (male and female C57BL/6) were trained to acquire food pellets via nose pokes at different costs (FUP).
• Activity was measured during voluntary wheel running (WR) or spontaneous locomotion (SC).
• Temporal patterns of food intake and activity were analyzed across the night.

Main Results:

• Wheel running (WR) increased food intake compared to spontaneous locomotion (SC) at all food prices.
• Males ran further and increased food intake more than females during WR, losing less weight.
• Increased eating due to WR was most pronounced early in the night, coinciding with peak activity.

Conclusions:

• Voluntary wheel running stimulates food intake concurrently with activity, without subsequent compensatory eating.
• Sex differences emerge in WR, with males exhibiting greater running and food intake responses.
• These findings highlight the interplay between exercise, energy balance, and temporal activity patterns.