The energy in the body is mostly heat or chemical potential energy, the heat would dissipate into the surroundings and the chemical potential energy would be transferred to whatever ate you or the cremating oven.
Science has a specific definition of energy which is the capacity to perform work that is to say effect a change. It is this that is conserved (that is to say that cannot be created or distroyed).
Energy is a property of an entity it does not exist in it's own right you cannot have "pure energy" in the way that some people love to talk about.
It does not flow along ley-lines and it does not go into "souls".
The energy in a human body is as Zevon says a combination of heat and chemical potential energy which can be liberated into the surounding environment when it is burnt or when it is consumed by micro-organisms and they use the chemical potential energy in their own life processes.