Final answer:
Using the Karvonen formula, the target heart rate (THR) for a 35-year-old female with a resting heart rate of 65 bpm at 70% exercise intensity is calculated to be approximately 150 bpm.
Step-by-step explanation:
The Karvonen formula is used to calculate the target heart rate (THR) for exercise, which includes resting heart rate (RHR), age, and intensity level. For a 35-year-old with a RHR of 65 bpm and an exercise intensity of 70%, we first calculate the Maximum Heart Rate (MHR) using the formula MHR = 220 - age. Thus, MHR for this individual is 220 - 35 = 185 bpm. Next, we determine the Heart Rate Reserve (HRR) by subtracting the RHR from the MHR: HRR = MHR - RHR = 185 bpm - 65 bpm = 120 bpm. After obtaining the HRR, we calculate the amount of this reserve to be used during exercise at 70% intensity by multiplying the HRR by 70% (or 0.7): 120 bpm x 0.7 = 84 bpm.
Finally, we add the RHR back to this value to get the THR: 84 bpm + 65 bpm = 149 bpm, which rounds to approximately 150 bpm.