http://todd.cleverchimp.com/blog/?p=125

It might be that an electric bike beats some diets, but some diets beat an electric bike.

If the food is available, eating more, and burning more, is a closer match to our pre-agricultural roots:

The average daily energy expenditure, as physical activity, of Stone Age humans is estimated at approximately 5.2 MJ (1240 kcal) and their total caloric intake at approximately 12.1 MJ (2900 kcal) (Cordain et al., 1998). Their subsistence efficiency was thus approximately 2.25 kJ (kcal) acquired for each kilojoule (kilocalorie) expended in physical activity. In contrast, sedentary humans in contemporary affluent societies commonly consume perhaps 8.5 MJ (2030 kcal) with expenditure, as physical activity, of approximately 2.3 MJ (555 kcal) (Cordain et al., 1998), a subsistence efficiency of 3.66 to 1.

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