Inference About Max's Condition

Emily has a pet dog named Max. Every morning, Emily takes Max for a walk in the park. The park is very close to her house, just a five-minute walk away. Max loves to play fetch with Emily, and he enjoys meeting other dogs at the park. After their walk, Emily always gives Max a treat for being a good boy. Today, Emily noticed that Max seemed a little tired after their walk. He didn't want to chase the ball as much as he usually does.