CPR is unlikely to restart a heart on its own. It's meant to keep oxygenated blood flowing between the heart and brain when the heart and lungs fail.
Going too far beyond what the body can handle with vigorous exercise, especially without taking time to build up to the level of exercise, is an example of overexertion.
Doing something over and over and over again can be defined as overexertion, which is something that is done excessively (too much). Overexertion without taking a break in between, which is significant for exercising, can cause damage to the muscles and other life threatening symptoms.
