Modern forms of transportation like automobiles can have a negative influence on physical fitness because _____

• A. They cause stress during traffic jams and this causes high blood pressure.
• B. They affect the amount of physical activity that people get.
• C. They cause accidents that injure people and cause them to be immobile.
• D. People have to spend more time at work to make the car payments.

Answer: (B)

The main idea is that modern transportation influences fitness because it changes how much physical activity people actually get. When cars are used for most trips, people substitute walking, biking, or other active choices with driving, so daily energy expenditure drops. Regular movement and progressive activity build and maintain cardiovascular fitness, strength, and flexibility, so fewer opportunities to move means fitness tends to decline. While traffic stress, potential injuries, or finances related to owning a car can affect health in various ways, the primary mechanism behind lower fitness with car use is the overall reduction in daily physical activity.