// Heart rate monitoring: the key to efficient training
Heart rate monitoring is not only an important component of cardiovascular fitness assessment; as an accurate indicator of the body’s physiological adaptation to the intensity of effort, it can become a highly effective tool for every training program, says Sian Cvorkov.
Monitoring your client’s heart rate is the safest and easiest way to keep them training at the right intensity; reducing their chance of injury or overtraining, and ensuring they get the desired results. Using a heart rate monitor provides you and your client with an accurate gauge of the intensity of their exercise. By constantly monitoring their heart rate you can ensure they are training in a manner that is tailored to their particular goal. You will learn to identify when their workouts are effective, when they are over- or under-training, and even when they may be getting sick or need recovery. For these reasons, it’s worthwhile refreshing your knowledge of maximum heart rate (Max HR).
What is maximum heart rate?
Maximum heart rate (Max HR) is the highest number of times the heart can contract in one minute. Max HR is the most useful tool in determining training intensities, because it can be individually measured or predicted.Factors influencing max heart rate include:
- Type of activity (sport/ muscle group-specific)
- Ageing process
- Exercise history
There are three ways to determine a maximum heart rate:
- VO2 max test
- Sub maximal heart rate test
- Age-predicted maximum heart rate formula.
VO2 max test
VO2 max is the maximum capacity of the body to transport and utilise oxygen during incremental intense exercise. It is measured as milliliters of oxygen used in one minute per kilogram of body weight.
Accurately measuring a VO2 max involves a physical effort sufficient in duration and intensity to fully tax the aerobic energy system. The exercise intensity is progressively increased while measuring ventilation, oxygen and carbon dioxide concentration of the inhaled and exhaled air. VO2 max is reached when oxygen consumption remains at a steady state despite an increase in workload. As a result, this test is extremely strenuous and must be performed under the instruction of an exercise physiologist or doctor.
VO2 max tests are generally considered the best indicator of an individual’s cardiovascular fitness and aerobic endurance. Theoretically, the more oxygen used during high level exercise, the more energy can be produced.
Sub maximal heart rate test
A sub maximal test is not as specific as the VO2 max test, but it is arguably the next best option and can be performed readily in the field. Here are a few examples of how you can perform a sub max HR test:
Example 1: Running
Ensure the heart rate monitor is set to display heart rate in beats per minute. Your client must first perform a 15 to 20-minute warm up with their heart rate gradually reaching 85 per cent of their maximum heart rate (220 minus age, see age-predicted maximum heart rate formula below).
Now, on a running track or other open environment, get your client to perform a two-minute run at maximal effort, recover for two minutes (either remaining stationary or walking slowly) and then perform a second two-minute run at maximal effort. Take note of the highest heart rate value reached either in the first or second interval and add five additional beats to the highest value. This number can be used as the client’s maximum heart rate.
Example 2: Cycling
Client must perform a 15 to 20-minute warm up, as per running test example above.
Now, at the base of a hill which has a steady gradient of approximately four to five per cent, get your client to perform a three to four-minute seated climb at maximal effort, in a gear that allows you to maintain a cadence of 60 to 70rpm (these conditions can also be replicated on an indoor cycle). Take note of the highest heart rate value reached and add five additional beats to the highest value. This number can be used as the client’s maximum heart rate.
Age-predicted maximum heart rate formula
The age-predicted maximum heart rate formula is a simple way to get an estimate of a maximum heart rate with some accuracy in adults. It is an extremely safe and effective way to establish a training zone for beginners and individuals training for a healthier lifestyle or for recreational sport.
The formula used to identify the age-predicted maximum heart rate is: 220 minus age. For example, the age-predicted Max HR for a 26-year-old is: 220-26 years = 194 bpm (beats per minute).
It should be remembered that there may be some discrepancy when using the age-predicted formula, especially in those who have been fit for many years or in older people. The formula will give an estimate to work from, but if you want to know a more accurate heart rate then a VO2 max test, or a sub-maximal test, should be performed.
Establish client’s heart rate zone
Once you have identified your client’s maximum heart rate, you can set their heart rate zone limits. The secret to training effectively and efficiently is to ensure that your client is working in the right heart rate zone for their exercise goals. In each zone their body will experience a different physiological effect; as a general rule, when exercise intensity is increased the duration of the activity or efforts should decrease (see Table A below).
|table a: Heart rate zone|
*Target Zones are fully customisable. Those who do not know their maximum heart rate can use HR Max = 220 minus their age as a general guide.
The Karvonen Method, which takes into account resting heart rate, individualises your client’s training heart rate range. Here’s how you do it:
Remember, if your client’s improved CV fitness is resulting in a lowering of their RHR, it’s important to redo the equation every few months to keep their training range as accurate as possible.
Most clients have limited time each week in which to train with you. A heart rate monitor allows you to help them make the most of each training session. By training more efficiently within a limited time, they will gain an advantage over those who may have more time but less knowledge about the way their body functions during certain exercise phases.
With a diploma in fitness, Sian has been working in the fitness industry for many years. She is employed by the leading heart rate monitor company, Polar, to write specialised courses in heart rate training. Sian is passionate about health and fitness and trains regularly in cycling, running and kickboxing. For more information visit www.pursuit-performance.com.au or call 08 8100 8604.