Load test | Beta-blockers and sport – how does that go together?

Load test

If patients suffer from high blood pressure or cardiac arrhythmia, they should also have a stress ECG if a beta-blocker is used, if it is planned to take up sports activities. Usually on a bicycle the patient has to pedal until a certain load is reached. At the same time, the heart currents are recorded by an ECG and the blood pressure is also measured at regular intervals.

Here it can then be seen whether the beta-blocker causes an increase in the heart rate necessary for sport or whether the blood pressure is not lowered too much so that not enough oxygen-rich blood can circulate in the body. As a rule, if you plan to start exercising, you should wait until you have taken the beta-blocker for about 1-2 weeks before taking it, as it will not take full effect until then. It should be noted that in principle it is possible to do sports while taking beta-blockers. However, in case of complaints, either the sporting activity or the beta-blocker should be reduced in its dosage.

What influence do beta blockers have on the pulse rate?

Beta-blockers, which are taken regularly by many patients as so-called antihypertensives or colloquially called “blood pressure tablets”, unfold their effect by blocking the stress hormones adrenaline and noradrenaline. They prevent these hormones from attaching to their target receptor and developing their stimulating effect. Consequently, the effect of the beta-blockers is almost exactly the opposite of the effect of the stress hormones in question.

While adrenaline and noradrenaline raise blood pressure, beta-blockers lower it. The heart rate – measurable as a pulse rate – also normally increases under stress and excitement. If this increase is blocked by beta blockers, the heart rate drops.

This is why the so-called bradycardia, i.e. the excessive drop in heart rate, is one of the most important undesirable effects of beta-blockers. The definition speaks of bradycardia from a heart rate of <50 bpm. Depending on the initial value of the individual patient, however, unpleasant side effects may become noticeable earlier. Due to the additional drop in heart rate caused by taking a beta-blocker, these should never be prescribed to patients in whom an existing bradycardia – for whatever reason – is already known.

What influence do beta blockers have on performance?

Basically, the drop in blood pressure and pulse rate, which is usually desired when taking beta blockers, leads to a weakening of the subjective performance. However, if blood pressure (and pulse) were very high before the start of therapy, this weakening can be just right and bring the desired effect. However, quite a few patients complain of listlessness, tiredness and dizziness, especially at the beginning of a drug therapy with beta blockers to lower blood pressure.

The other extreme occurs in very nervous, excited or even anxious patients: For this group of people, beta-blockers have a calming effect by lowering blood pressure and heart rate and reducing stress levels, which can possibly increase performance. As excessive nervousness is buffered, fewer careless mistakes caused by excitement occur and the ability to concentrate increases. For this reason, beta-blockers are used in addition to the therapy of high blood pressure, also in patients with severe stage fright, exceptional test anxiety or panic attacks. The editors also recommend: beta blockers and alcohol