Final answer:
A 20-year-old person with an 'Excellent' VO2max should start exercising at a target heart rate range of 120 to 160 bpm for optimal cardiovascular benefits, making option C (130-178) the closest correct answer, with a note to stay ideally within the 120-160 bpm range.
Step-by-step explanation:
The question at hand involves determining at which training intensity a 20-year-old person with an 'Excellent' VO2max rating should start working out, based on the Maximal Heart Rate Method. Typically, the maximal heart rate (HR) can be approximated as 220 beats per minute (bpm) minus the individual's age. Therefore, for a 20-year-old, the estimated maximal HR would be 200 bpm (220 - 20 = 200 bpm). When working out, it is essential to maintain a target heart rate range that optimizes cardiovascular benefits without overstraining the heart. According to the provided information, the safe and effective target heart rate range during aerobic exercise for maintaining cardiac output (CO) is between 120 and 160 bpm. Training above this range, particularly above 160 bpm, can lead to a decrease in stroke volume (SV) and, consequently, in CO, which is not desirable for optimal aerobic conditioning.
Therefore, for a 20-year-old person whose cardiovascular endurance is rated 'Excellent,' starting exercise intensity should ideally be within the range of 120 to 160 bpm, accordingly making option C (130-178) the closest correct answer among the available options. However, note that the upper limit of 178 goes slightly beyond the recommended 160 bpm for maintaining CO, and attention should be given to staying within the safer range of 120-160 bpm.