When you do intensive exercise, you require more oxygen and thus accelerate your heartbeat. But what is a good, normal, or even dangerous heart rate?

Quiz question: two women with the same weight, height, age and 10-km best time go jogging together. Will they also have the same heart rate when jogging?

Of course not, you will argue - and will naturally be right. This is because the human heartbeat is as individual as the person carrying the heart. A person’s heart rate says correspondingly little about their performance. Unless you compare your own values with each other. But first things first.

Playing with numbers

In endurance sports, heart rate values are constantly plagued by numbers and formulas. Your maximum heart rate is 220 minus your age, for example. This formula is in fact not a bad approximation of the maximum heart rate, as it considers the fact that the maximum heart rate decreases with age. Whereas a young heart can easily achieve up to 220 beats, this significantly decreases in old age, whereby the norm tends to be somewhere between 160 and 180.

The following example shows how a rule of thumb is always only an approximation. The maximum heart rate was determined by simply taking a certain number of heart rate values as a reference, calculating the average, and finding a formula that came closest to this average. Thus, if a thousand people have a maximum heart rate of 190 and 1000 have one of 170, then the average value is 180 – which is quite close to the real value of all 2000 people, but still incorrect.

Utilise the entire spectrum

In endurance sports, it is basically a matter of utilising the entire bandwidth of the human heartbeat – from the resting heart rate during sleep to the maximum heart rate under a heavy load. In the case of well-trained endurance athletes, this spectrum normally lies between about 50 to over 200, as already mentioned. As it is barely possible to deliberately overload a healthy heart, it is not dangerous to push your personal limits in a competition.

The more often the human heart is exercised, the more powerful it will become and thus able to pump more oxygen through the body with each beat. As a result, the resting heart rate will decrease. Sporty and active people have a correspondingly lower resting heart rate than smokers and inactive (as well as overweight) people, whose resting heart rate can increase to 90 beats per minute. This also means that in everyday life, an athlete’s heart needs to work much less than that of an inactive person. For example: a difference of 40 beats per minute means a difference of 2400 beats per hour which in turn means that an untrained person’s heart needs to beat a whopping 57,600 times more per day! And even if the athlete does one hour of sport a day at a heart rate of 150 and thus generates an additional 9,000 beats, the total daily number is about 50,000 heartbeats below that of the non-athlete. 

Maximum heart rate as a guideline

In sports, utilising the entire spectrum of the heartbeat means training at different intensities. When training over a longer duration (endurance runs, bike trips), the range normally lies between 110 and 150 beats, with shorter and intensive units, the heart rate shoots up correspondingly higher. In practice, the maximum heart rate has proved to be a good guideline for determining the individual intensities. The maximum heart rate can be used as a base to define the different performance zones (e.g. 90% of the MHR, 80%, 70%, etc.).

You don't know how high your maximum heart rate is? Then try the following: After a 10-minute warm-up run or cycle, slightly increase your tempo on a gentle and steady gradient for about two to three minutes until you are running at maximum speed for the last minute. Measure your heart rate at the end of this last minute. But watch out: untrained people need to exercise caution when determining their maximum heart rate. If you are over 40 and/or have not yet done any training, you should first get a medical check-up.

Considerable daily fluctuations

And there is something else you should bear in mind when it comes to heart rate values: your heart rate is not always the same in every situation but varies to a certain degree from day to day. It is therefore very interesting to see how your heart rate changes during individual activities or how high it is after getting up, for example. Increased heart rate values in the morning can indicate a possible infection or insufficient recovery as can a heart rate value that is higher than normal at the same speed. A maximum heart rate is also dependent on how hard you can push your limit and in which type of sport you measure it. The same athlete will not have the same maximum heart rate in swimming as in running or cycling. 

When it comes to a competition, everything is different again. Due to nervousness, it is quite possible that your heart rate is higher than normal in the competition. Furthermore, the outside temperature, topography of the route, and your form on the day will influence your heart rate. Heart rate values or heart rate limits can help the beginner not to take off too quickly in the initial phase of a competition. However, it also makes sense to listen to your feelings and run without monitoring your heart rate. You can still record the data because it will provide important insights and show whether your feelings are deceptive.

It is quite possible that it will also be the same for the two women we mentioned above, if they achieve the same time at the next competition. But it is also likely that one has a completely different running heart rate than the other.

Foto:iStock.com