I bought a minivan for my new car in part because it can hold my tricycle for trips to the bicycle repair shop. And of course it does not get the gas mileage of a regular car. Such are the contradictions of the human condition.
If I am alive a year from now, I can presume the excercise has extended my life span. If I die in a car accident or from a heart attack, then it did not. If I am hit by a car and severely crippled, then it will make for a grand philosophical debate. Let's hope for the first option.