The power generated by a system is defined as the work performed per unit of time:
\begin{equation}
{P = \frac{\mathrm{d}E}{\mathrm{d}t}}
\end{equation}
This relationship applies not only to mechanical energy, but also to all other forms of energy, which will be discussed in the following chapters. If equal amounts of energy are converted in equal periods of time, this differential quotient can be simplified to the following form:
\begin{equation}
P = \frac{\Delta E}{\Delta t}
\end{equation}
The concept of power will be discussed in more detail using a medical example: For a healthy adult with a mass of 70 kg, the hemoglobin is approximately $5\cdot 10^6\,\mu\mathrm{l}$. During strenuous activity, the human heart can beat up to 150 times per minute, pumping 175 cm3/s of blood through the body with each beat. If we consider that four oxygen atoms can bind to each of these protein complexes, this means that the equivalent of 3.5 1017 oxygen atoms, or 580 10-8 mol per second, are transported to the muscles, where they can react with sugar molecules. Sugar has a molar mass of approximately 342 g/mol, meaning that 0.019 g of sugar per second can be burned. The calorific value of sugar is approximately 17 kJ/g, and the efficiency of the muscles in converting this energy into mechanical work can be assumed to be 25%. Multiplying these values together, we find that an average person can generate about 80 W of power, which corresponds to a height difference of about 10 cm/s when substituting this value into the formula for the potential. This is, of course, only a very simplified calculation, but it is very close to the value for average human power given in the literature. However, a person can generate much more power for a short time. Depending on the situation, this can be up to 2 kW.