Final answer:
The target heart rate is the range in which your heart should beat while exercising, calculated as a percentage of the maximum heart rate, which is estimated by subtracting your age from 220 bpm.
Step-by-step explanation:
The target heart rate is the range in which your heart should beat while exercising to achieve cardiovascular benefits without overexertion. Target heart rate zone is typically calculated using a percentage of your maximum heart rate, which decreases as you age. To estimate your maximum heart rate, you can subtract your age from 220. For example, a 40-year-old's maximum heart rate would be roughly 180 beats per minute (bpm), and their target heart rate would be a percentage of that maximum.
It's important to stay within your target heart rate zone to improve your heart's efficiency and overall cardiac reserve, which is the difference between maximum and resting cardiac output (CO). Cardiac output increases with exercise, thus working out within your target heart rate ensures effective training for your cardiovascular health.