I voted "Just commute for some, fitness/transportation but no real training"
The main reason for my commuting is the fitness aspect. It is the easiest way for me to get some exercise. I also like to keep the the miles off of my truck, especially now with gas around here at about $2.12 a gallon. I have found myself riding more to the store and a few other places. The transportation aspect is becoming more of it.
Like you, maybe a couple days of week I will go all out on my commute, but most days it is a low impact ride.
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