No. As handsonanatomist mentions it has to do with blood flow to the myocardium(heart muscle itself). The heart muscle itself only receives oxygen during diastole(relaxation), but as heart rate increases the relative length of diastole shortens compared to systole(heart contraction). TLDR; your heart gets tired because it only gets oxygen while relaxed, and the relative amount of time spent relaxing is less.
Mind vs Brain. Though mind and brain are two terms that are understood to mean the same when used in the colloquial sense, there is a difference between mind and brain. There is certainly some difference between the two in their making. Brain is made of physical matter while mind is not made of physical matter. To be more elaborate brain is made up of cells, blood vessels and nerves to name a few. Mind is nothing but the thought that resides in the brain.
What is the difference between Autobiography and Biography? â¢ An autobiography is the life story of a person written by that person. On the other hand, a biography is the life story of a person written by another person. This is the major difference between autobiography and biography. â¢ An autobiography, since it is written by that same person, may not be complete. It can contain only the event the person considers important to him.