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25 Nov 2004

gym cycle bike / treadmill sensors

I would just like to know, I have just started at gym. On the cycling bike it says my heart rate should be 127. The cycle bike and treadmill measures your heart rate by you putting your hands on sensors. How accurate do these machines measure your hart rate via these sensors? Thanks
Answer 364 views

01 Jan 0001

HI Lady

The sensors are pretty accurate - these days, they have got these things so sensitive that they can pick up pretty weak signals, and there's actually quite a strong pulse in the hands, which the silver sensors are able to pick up easily. From experience, I've compared the accuracy on the gym machine with the more accurate Polar heart rate monitor signal, and they are the same, so it's an accurate signal.

How important heart rate is is another question. Heart rate is a useful training tool if used wisely, and it can help prevent overtraining and thus optimise performance. However, there are a few basics that are important.

This depends on many factors, such as the intensity with which you are training and genetic factors. However, here are some general facts about heart rate, and a suggestion about the best way to use your heart rate monitor during exercise.

First, some terms which are used often, namely resting heart rate and maximum heart rate:
Resting heart rate varies widely between individuals. A normal resting heart rate for a moderately fit person is between 60 and 70 beats per minute. Fit people tend to have lower resting heart rates, but this is only a general rule and not always the case. Your resting heart rate will probably decrease slightly as you improve in fitness.

Your ideal max heart rate is roughly given by the equation 220 minus your age. This provides an estimate for max heart rate. When you train for general fitness and weight loss, it is best to train at an intensity that corresponds to between 70 and 90% of this maximum heart rate. For example, you might do a 40 minute run at 75 to 80% of maximum, and this is a good session for weight loss and improved fitness. Generally, aim to train for between 30 and 45 minutes per session (at least) and on 4 to 5 days per week. The intensity, as mentioned, will range between 70 and 90% of maximum, depending on the exercise you do and the goals for that session. For improved performance, train at 85% of max and above. For weight loss and fitness, train at between 70 and 80% of maximum.

Do not get caught up in to believing the heart rate monitor as the final authority in your fitness level. When machines are claiming that you should be at 127, you have to wonder how they know this - they use generic equations, derived from a large population, but the assumption is that you are the same as everyone else, and this is hardly ever true. The best way to use your heart rate monitor is to use it to compare training sessions from week to week. Therefore, if you train one day doing a particular session, take note of your heart rate. The next time you do the exact same session (say 30 minutes walk at 7 km/hour), you should be able to compare your heart rate during the session. If it is lower, then it indicates that you are fitter than before, and your training is going well. If it is higher, then it shows that you are either tired, or training too hard or are possibly becoming ill. This is a sign that you are in need of a few easy training days.

It is important that you don't think of heart rate as the absolute indication of fitness or health. It is the differences between heart rates in exactly the same session that is important, and understanding how your own individual heart rate differs from week to week will allow you to train with great precision.

Lastly, remember that heart rate depends on many factors - hydration, mood, stress levels, temperature and so on. Therefore, if your heart rate is not exactly what you think it should be, don't worry too much. Rather look at long term changes and patterns in heart rate, and try to interpret them as I explained above.
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