"Warm, sunny days, cool evenings and postcard perfect colors... ...get outside and enjoy the season by bicycling, walking, hiking, jogging, and playing golf and tennis. Explore parks in your area; find a new bike path through the woods, take a walk around a lake. The time spent out in nature will do as much good for your mind as for your body."
Zwiefel also says that the reason autumn is a good time to get reacquainted with INDOOR exercise is that the HABIT will take 21 days to form (Hey! We knew that!), so people who get used to using some autumn days to get back to indoor exercise are more likely to keep up regular workouts when the weather turns cold, rather than dropping it. He also has a definite preference for an autumn fruit:
"An apple a day: In many parts of the country, autumn is synonymous with the apple harvest. Rich in antioxidants and flavonoids, both of which reduce the oxidation of LDL cholesterol, inhibiting the growth of dangerous plaques along blood vessel walls, and dietary fiber, apples are a delicious and nutritious snack that can be enjoyed any time of day.
"Remember that each of us should be getting at least four to five servings of fresh fruit and vegetables every day. However, nine out of 10 Americans do not meet these recommendations. "
Gee! We Americans need to stock our crispers!