Yes. Seriously. How many extra carbs do you burn to walk a mile? Those end up in the atmosphere as CO2. There's no free lunch, so to speak. Given that animals

Yes. Seriously. How many extra carbs do you burn to walk a mile? Those end up in the atmosphere as CO2. There's no free lunch, so to speak. Given that animals aren't super efficient already, I wouldn't be surprised to learn that something like a moped puts less CO2 in the air to move a sedentary human compared to a human that's huffing and puffing CO2.