Final answer:
The underlying problem is angina, which is chest pain or pressure that occurs when the heart muscle does not receive enough blood flow. The patient's symptoms are consistent with stable angina, which is triggered by exertion and improved with rest.
Step-by-step explanation:
The underlying problem in this case is angina. Angina is chest pain or pressure that occurs when heart muscle cells do not receive adequate blood flow and become starved of oxygen. It can be classified as stable angina, which is triggered by exertion and is relieved quickly with rest, or unstable angina, which occurs at rest and lasts longer than 15 minutes. The symptoms described by the patient, including chest pain during exercise that resolves with rest, are consistent with stable angina.