Both of these questions came within 24 hours of each other, so Alice is posting both! Yes, question 1, your husband is correct, there is a heart rate zone that will result in cardiovascular benefits. So, here's a general rule to determine your target heart rate range for exercising.

Maximum heart rate is approximately 220 beats/minute minus a person's age. You want to exercise, on the low end, at 60% of that number, and on the high end, at 85 - 90%. Let's say you are 30 years old. Subtract 30 from 220 and you get 190. Sixty percent of 190 is 114 beats/minute. Ninety percent would be 171 beats/minute. So your range is 114 - 171. After you have exercised for about 5 minutes, check your pulse. You can take it for 10 seconds and multiply by 6, or for 15 seconds and multiply by 4, to determine beats/minute. If you are too low, you can increase your pace, switch to a lower gear while cycling, or swim faster. If it's too high, slow down.

Alice wants you to know that the recent recommendations by the Centers for Disease Control and Prevention (CDC) and the American College of Sports Medicine stress 30 minutes or more of moderate-intensity physical activity on most, and preferably all, days of the week. Moderate activity can be equated to walking briskly at 3 to 4 mph (20 minute or 15 minute miles). Based on epidemiological research, protective effects have been associated with regular moderate physical activity and heart disease, hypertension, non-insulin-dependent diabetes mellitus, osteoporosis, colon cancer, and anxiety and depression. If you exercise at a low to moderate intensity, it is also more likely you will continue to exercise than if you exercise at high intensity. Setting goals and monitoring your progress will also help you to keep going. And if you have a hard time setting aside 30 minutes all at one time every day, the new guidelines recommend shorter bouts of 8 to 10 minutes totaling the minimum 30 minutes on most days. Isn't this exciting?

For Question 2, indeed 20 minutes of aerobic exercise 3 times a week is a good schedule for minimum benefits. You will want to gradually increase your time and the days of the week as you get fit. And, don't forget to add strength training and flexibility exercises to your program.

Keep up the good work and keep track of how you're feeling!

Alice

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