Final answer:
The target heart rate for a 40-year-old man with a resting HR of 70 bpm exercising at 65% intensity is approximately 142 bpm, using the Heart Rate Reserve method.
Step-by-step explanation:
To calculate the target heart rate (HR) for a 40-year-old man with a resting HR of 70 bpm exercising at an intensity of 65% using the Heart Rate Reserve (HRR) method, we follow these steps:
- First, calculate the maximum HR by subtracting the man's age from 220. In this case, 220 - 40 = 180 bpm.
- Next, determine the heart rate reserve by subtracting the resting HR from the maximum HR. For a resting HR of 70 bpm, the HRR is 180 bpm - 70 bpm = 110 bpm.
- Calculate 65% of the HRR, which is 0.65 x 110 bpm = 71.5 bpm.
- Finally, add the resting HR back to this number to get the target HR for 65% intensity: 70 bpm + 71.5 bpm = 141.5 bpm.
Therefore, the target HR for a 40-year-old man exercising at 65% intensity, with a resting HR of 70 bpm, is approximately 142 bpm.