Target Heart Rate Training is a systematic method of improving your cardiovascular fitness. By exercising at sufficiently intense levels, you can overload your cardiovascular system. During rest, your body adapts to strengthen the cardiovascular system. Over time, your heart becomes more efficient at delivering the oxygen and fuel required by the muscles to maintain this higher level of performance. The skeletal muscles also become better at extracting oxygen from the bloodstream. With continued consistent exercise, the cardiovascular system continues to consistently improve.

 How do you know how hard you are working out? The difference between the volumes of oxygen exchange during exercise is what the muscles used to burn fuel (mostly carbohydrates and fat). The rate of this oxygen consumption is called VO₂ As you exercise at progressively more difficult levels you will reach your maximum capability. This maximum rate of oxygen consumption is called the VO2 max.  This is the best way to measure exercise intensity.

The second best way to measure exercise intensity is your heart rate during exertion. The heart rate is much easier to measure than VO2 but it is a very good approximation of VO2. This means that if you know your maximum heart rate (the fastest your heart rate is capable of pumping), you’d have a convenient method of monitoring your workouts.

 To accurately determine your maximum heart rate, subtract your age from 220 then multiply that number by 1 (or 100%).  The result will represent the maximum number of beats per minute at 100% of your cardiovascular efficiency.

Knowing your maximum heart rate will allow you to estimate where you can train to bring about cardiovascular improvements. The maximum heart rate formulas provide an approximation of your true maximum heart rate. But by estimating conservatively, you can use these estimates as the foundation for monitoring your exercise intensities.

 Once you’ve determined your estimated maximum heart rate, you can construct a “target zone” for your workouts. Normally, trainers specify “zones” for you to work in. This is because the human heart rate changes continuously. It would be virtually impossible to maintain any selected heart rate. In addition, it takes a while for the heart to “come up to speed.” For these reasons, a “target heart rate zone” has evolved to become the most practical method of measuring exercise intensity.

Target heart rate zones are expressed as a percentage range based on your maximum heart rate. For instance, your goal may be to maintain your heart rate of between 124 and 144 bpm (beats per minute). For tracking purposes, you would most often only track the duration of your exercise in which you were between your minimum and maximum heart rate goals (your duration “in the zone”).

Most training schedules incorporate different types of workouts (e.g. long, slow distance, high intensity intervals). You can construct different target zones depending upon the type of workout you are performing. Heart rate monitors can help you stay in that zone so that you can achieve your goal for that workout. The heart rate monitor will tell you the amount of time you were in your target heart rate zone. This makes it far more convenient to track your workouts.

Target heart rate training lets you track improvement over time. This is indicated by a gradual reduction in your resting heart rate. Another indicator of improvement is that you’ll need to perform at higher levels to perform the same exercise at the same heart rate range as before. For instance, you may find that you need to run on a treadmill at say, 4.5 mph to stay in your target heart range when you first start out. You will find that over time you will have to run at, say, 4.8 mph to get your heart to stay inside your target heart range.

Target heart rate training provides a scientific approach to tracking your improving levels of fitness. Heart rate monitors allows you to measure exercise intensity independently of what activity is being performed by focusing on heart rate as the measure of exercise intensity.