Cardiovascular training, or aerobics, requires a different approach than other body parts. At the “heart” of cardiovascular training is one basic premise: if you elevate your heart rate to 65-80 percent of your maximum and keep it there for a period of at least 12 minutes it will stimulate the production of fat-burning enzymes. It will also strengthen your heart and increase the capacity of your lungs to re-oxygenate your blood more efficiently.
The idea here is not to work yourself to a frenzy and go beyond your target heart rate, but to stay within that magic training range of 65-80 percent of maximum for a minimum of 12 minutes and, optimally, for 20 to 30 minutes. Training for longer periods will certainly hasten your improvement, but not on a 1-to-1, linear basis. Research has shown that the first 12 minutes of aerobic exercise produce a more lasting training effect than the second 12 minutes.
So unless you’re already in pretty good condition, it’s probably better to do your 12 minutes more frequently (say 4-6 times per week) than it is to train for longer periods of 30 minutes or more but less frequently. Walking, jogging, running, cycling, rowing, jumping rope, running in place, and aerobic dancing are all fine.
As long as your heart rate is elevated into your training range and remains there for 12 minutes minimum, any of these activities will do a pretty good job. To determine your training range, simply calculate the lower limit at 65% of your Age-Predicted Maximum Heart Rate and the upper limit at 80% of your Age-Predicted Maximum Heart Rate. Age-Predicted Maximum Heart Rate = 220 minus your age. If you’re 45 years old, for example, your lower limit is 220 – 45 x 0. 65 = 114. Similarly, your upper limit is 220 – 45 x 0. 80 = 140. If you elevate your heart rate to between 114 and 140 beats per minute continuously for at least 12 minutes, you’ll get the desired training effect on your heart. It takes a few minutes of exercise to elevate your heart rate into your training range.
This time does not count toward your 12 minutes. Check your pulse by resting your index and middle fingers lightly against the carotid artery on either side of your neck underneath the curve of the jawbone. Count the beats for 6 seconds and multiply by 10 to calculate your heart beats per minute. Or, for a rough estimate, you can use the “talk test. ” If you’re gasping and panting so much that you are unable to talk, then you’re probably exercising too hard and are beyond your training range.