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human
[Avatar:TLA/Avatar:LOK] Nutrition wise how much energy does the various types of bending use?

Iirc bending is not treated as magic, it comes from the benders bodies and can even >!spoiler Be cut off from the users bodies by constricting bloodflow!< So what is the energy cose of bending? Would a intense bendong fight burn callories like one in martial arts or a full session in the gym?
gpt
In LoK, we see that pro benders get tired out during rounds, and throughout each series, we see that bending causes physical strain on the body, but it doesn't seem proportionate to energy consumption. For instance, tiny little 12 year old Toph can hold up an entire massive library to keep it from sinking in the sand, but during a 2 minute round of a pro bending match, top athletes get too tired to fling a water whip anymore. Theres also the case of the first blood bender being able to control a guard using one of the most difficult bending techniques while she was in incredibly poor health. 

Bending is not about nutritional energy consumption like muscles in the body. It's about chi and spiritual energy. It doesn't seem to be a straight 1:1 ratio. And bloodbending being used to block bending seems to be more about blocking the flow of chi through the chakras. The spiritual energy for bending flows through the body along certain paths, and can be blocked by manipulating the body, but it isn't depended on physical stamina and nutrition. After all, the best earthbender of all time was a 3 foot tall, 12 year old blind girl, not a jacked dude in great condition.

Also, if bending relied on caloric intake, then we probably would see benders scarfing down food the second a big fight ended, or carb loading before a big probending match.