If it's on TV it's gotta be true!
The need for exercise for the general population is a relatively new problem facing society. Work is becoming paradoxically increasingly less exercise intensive. (c)
As manual labor jobs are replaced with mechanical systems and people move to the office or unemployment line instead, the need for exercise goes up. Regardless of how one may feel about human instinct, exercise is definitely not something I would consider instinctual for any animal. It's only because we live in an unnatural world we must do such unnatural things as exercise.
b