An athlete wants to know if he is exercising at an appropriate level of intensity during his workouts. What information does he need to find?

He must find his low heart rate zone.

He must find his target heart rate zone.

He must find his average heart rate zone.

He must find his resting heart rate zone.

A62-year-old man is being treated for an acute myocardial infarction. he originally came to the ed with substernal chest pain and diaphoresis. given his risk factors of hypertension, diabetes, tobacco use, and family history, he is considered high risk. an ecg in the ed reveals a left-bundle branch pattern, and cardiac enzymes are elevated slightly. after a focused evaluation in the ed, the patient receives iv thrombolytics. although his bundle branch pattern never resolves, the patient is chest pain-free and haemodynamically stable after thrombolysis. two days later, however, the patient reports episodes of recurrent chest discomfort and shortness of breath overnight. in evaluating for potential myocardial reinfarction, which of the following is the most appropriate diagnostic test? - creatinine kinase- dynamic ecg changes- lactate dehydrogenase- myoglobin levels- troponin i level