When energy is burned in the human body what happens to it?

Movement. Heat.

It’s burned and your body exhausts it. You know when your run or exercise you feel hot…there it goes.

@TheLoneMonk
I don’t know if you were but it sounded like you were not including the actually exercise only a byproduct that is heat.

Naa…just one example.

Sweat from our pores I would imagine. I don’t think you can see the energy leaving your body unless you had some sort of thermal goggles on that you can see heat leaving the body. Sweat is merely a waste from our body to indicate you’ve been spending energy.

Watch a football game on TV and see the players heads steam in cold weather. Energy exhaust.

This question requires a fairly detailed answer, but I will do my best.

First energy is not burned. Energy is converted. When you eat the body processes nutrients. Some of these are use immediately, others are stored as carbs and fats.

These nutrients have potential energy that is converted by the body to kinetic and thermal energy to do “work”.

So some of the energy becomes heat and some becomes movement.

Yes, as @tekn0lust said, and it may be important to note that energy can not be created nor destroyed, but only converted from one form to another.

excellent…so when I’m walking; the energy being used in my legs gets transferred to the floor and air particles around my legs? Is this correct?

@lynneblundell

Yes, at a very high level that is correct.

thanks @tekn0lust that’s really interesting… I’m just thinking now about energy transference and good and bad energy etc…Are there differences molecularly between different types of energy..say for example the energy emitted by me walking rather than my son walking…. is the structure different in way..or could it be?

Just for reference, when we design a building’s HVAC system, we figure about 100 watts per person for an office. So if it’s chilly in your house invite a bunch of friends over.
Feels warmer already doesn’t it?

@lynneblundell

Wow you are getting pretty deep there. I don’t believe there is any difference in physical energy between two different humans other than the amount used maybe. AFAIK the laws surrounding energy are pretty well understood. If you want to really get into it research the laws of thermodynamics.

The key to understanding this is to think of the body as a machine. Way down at the cellular level a muscle cell has tiny mechanisms which contract the cells to make their shape change. When these cells work in concert to make a muscle contract they drive the skeletal structure that they are attached to. One of the by products of this is heat the other is the work which creates the forces which move the body.

The video on this page shows the “machine” in action.
http://health.howstuffworks.com/muscle.htm

@tekn0lust I’ll have a look at that now thank you… x

that’s cool…will have a look at thermodynamics too…. thanks again tekn0lust

If you want to look at energy in terms of personal output, I would offer the following:

-Energy required for your son to walk versus the energy required by you would depend on mass and form. The larger or less coordinated the structure, the more energy required.

-The total output of energy by some people can be significantly less depending on the amount of entropy in their system.

This is based on the first and second laws of thermodynamics, as I understand them. Though, I fully admit to my lack of study in this area.

First law of thermodynamics
   -Energy can neither be created nor destroyed. It can only change forms.
   -In any process, the total energy of the universe remains the same.
   -For a thermodynamic cycle the net heat supplied to the system equals the net work done by the system.

Second law of thermodynamics
   -The entropy of an isolated system not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium.