A Runner’s Heart: What You Need to Know Before a Run

There are less than four weeks to go until the anniversary Almaty Marathon. The bulk of your training is behind you. A key priority for every runner now is to maintain fitness and arrive at the start line without risking their health.

How does the heart respond to running, why is it important to monitor your heart rate, and which symptoms during exercise should not be ignored? Inna Leshchinskaya-Popova, a cardiologist and Master of Medical Sciences, answers all these questions.

What Happens to the Heart While Running?

During a run, muscles require more oxygen and nutrients, so the heart works harder. It pumps blood at an accelerated rate, delivering blood to organs and tissues while helping the body flush out metabolic waste.

As the intensity of the exercise increases, your heart rate rises, and the volume of blood pumped per minute expands accordingly.

How the Heart Adapts to Exercise?

With regular exercise, the heart gradually adapts and begins to work more efficiently. It can pump more blood with each beat, so at rest it does not need to beat as often. Well-trained runners may have a resting heart rate of around 40–50 beats per minute.

Other aspects of cardiac function may also change. For example, the electrical impulse triggering a heartbeat may travel slightly slower, and the heart rate may accelerate during inhalation and slow down during exhalation. Such changes in well-trained people may be the result of adaptation to regular exercise and do not always testify to a medical condition.

When Can Running Be Dangerous? 

People with high blood pressure should be particularly cautious about intense physical exertion. Blood pressure should be monitored and, if necessary, reduced to target values using treatment prescribed by a doctor. You should only return to intense training with your doctor's permission once your condition has stabilised.

However, you should not rely solely on blood pressure. It is important to take into account your general well-being, diagnosis, any medication you are taking and your doctor’s recommendations.  Even if your blood pressure is normal, you should reduce your exertion or stop running if you experience dizziness, blurred vision, nausea or other unusual symptoms during a run.

Why Heart Rate Monitoring Matters

Regardless of whether you have cardiovascular disease, it is important to monitor the intensity of your training sessions. Heart rate remains one of the most accessible indicators.

To establish your heart rate zones, let’s start by calculating your estimated maximum heart rate using the following Tanaka formula:

Maximum heart rate = 208 − (0.7 × age)

For example, for a 30-year-old man, the calculation looks like this:

30 × 0.7 = 21
208 − 21 = 187

The estimated maximum heart rate would be around 187 beats per minute.

For reference:

• Age 20 – appr. 194 bpm;
• Age 30 – 187 bpm;
• Age 40 – 180 bpm;
• Age 50 – 173 bpm;

It is important to remember that your maximum heart rate is not the pace at which you should run a distance. It is an approximate upper limit used to calculate training zones and intensity of exercises. Values may vary from person to person.

For more precise heart rate zones, you can undergo a stress testing at a sports medicine clinic. A chest strap will help you monitor your heart rate during a run.

Which Symptoms Should Never Be Ignored?

An increasing heart rate and breathing rate, sweating and tiredness are the body’s natural response to physical exertion.

However, there are symptoms that indicate you should stop running:

• chest pain or tightness;
• severe shortness of breath;
• dizziness;
• sudden weakness;
• skipped beats or irregular heart rhythm.

If these symptoms occur, please stop running. If they are severe or do not disappear after stopping, it’s recommended to seek medical advice.

People with high blood pressure are advised to consult a cardiologist before starting intensive training or taking part in a run. Before your appointment, you should keep a blood pressure diary for 5–7 days to show your doctor how your rate has changed over time. It is also advisable to prepare a list of medicines you are taking and previous medical examinations, even if they relate to other reasons.

If You Travel from Another City or Country

It is important for runners travelling to Almaty from other cities and countries to bear in mind the city’s altitude above sea level. Your body may need time to adapt to the new environment.

If possible, Inna Leshchinskaya-Popova recommends arriving a few days, or better a week, before the run – especially for those who live at lower altitudes. Conditions vary even within different parts of Almaty: the higher the area, the thinner the air becomes.

The cardiologist advises against flying in the day before the race and participating in the marathon the very next day. A few extra days will help your body adapt to Almaty and ensure you’re better prepared for the run.

The most important thing before the race is to avoid pushing your body to its absolute limits at any cost. Monitor your heart rate and overall well-being, don’t ignore any unusual symptoms and, if necessary, consult a doctor. The real victory is to finish without harming your health and to remain able to take part again in future running events.