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How quickly your heart rate returns to normal after exercise can reveal a surprising amount about your underlying health
If your heart hammers in your chest when you walk up the stairs, or you need to gasp for air while jogging to catch a bus, it may be a sign that you are not in peak physical shape
Yet what happens after you stop exercising can be just as revealing about the inner workings of your body. Enter the heart rate recovery (HRR) test. This is the difference between your pulse when your heart is pumping hard during exercise, and how fast it beats about a minute after you have finished.
Nieca Golderberg, a cardiologist at New York University Grossman School of Medicine, explains that HRR is a good indicator of your cardiovascular health. It can predict high blood pressure and cardiac events
But your HRR is also so much more than that. A poor result can act as an early warning sign, helping to uncover hidden problems with the rest of the body. Crucially, that includes your overall risk of death
Back in 1999, scientists from the Cleveland Clinic, Ohio, published some striking results. They had tested the HRRs of 2,400 adults, then followed them for six years. The team found that people with low heart rate recovery were around four times more likely to die during the study period.
Other teams around the world have since found similar results. HRR has emerged as a surprisingly strong predictor of death from any cause, whether there seems to be anything wrong with your heart or not. In young adults and the middle aged, HRR is even more closely linked to your risk of death than high blood pressure.
Here’s a quick, simple way to calculate your HRR using materials you’re already likely to have at home.
*It’s important to consult your doctor before starting a new exercise regime. If you experience dizziness, chest pain or tightness, or shortness of breath that’s out of proportion to the exercise you’re doing, stop immediately. This test is not suitable for people with pre-existing heart conditions without medical supervision
The first step is to make sure you have a way of writing down your data and a timer (most phones have one). If you have a smartwatch or other wearable activity tracker, this will be useful
Then you need to calculate your maximum heart rate. If you have a smartwatch or other wearable device, this will be able to tell you what yours is. If not, this is usually around 220 minus your age
Next, it’s time to do some exercise. This should be intense enough to raise your heart rate to between 70 and 85% of its maximum. It could include running, cycling, or rowing, depending on your level of fitness
To calculate your HRR, measure your pulse immediately after you stop exercising, when it is still at its highest. The easiest way to do this is with a smart watch or a fitness tracker.
Alternatively, you can also hold a finger against your neck and count the beats for 10 seconds. Multiply this number by six for an approximate beats-per-minute
Next, rest for one minute by sitting or lying down and re-check your pulse. Then simply subtract the second number from the first. This is your HRR
You want your heart rate to drop back to normal quickly after you finish exercising. The more quickly it drops, the better. A good recovery rate would be one that goes down by at least18 beats in the first minute.
The number can also vary between individuals and depends on factors such as age
However, a HRR of fewer than 12 beats could put you at risk of health problems down the line
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The link between HRR and a person’s risk of death is thought to be down to the vagus nerve. This major nerve is a critical link between the brain and the rest of the body, relaying signals to and from the heart, liver, intestines and other organs. It controls whether you are in the more stressful fight-or-flight mode, or the more relaxed rest-and-digest state.
“We have these two systems that work on the heart, we’ve got a brake and we’ve got an accelerator,” says Lindsay Bottoms, professor in exercise and health sciences at the University of Hertfordshire, UK
When you exercise, the accelerator – also known as the sympathetic nervous system – activates, causing the body to enter “fight or flight” mode. Your heart beats faster and your blood vessels dilate, allowing oxygen to be pumped to the muscles
When you stop working out, your body needs to clear out all the metabolic “debris” created during exercise, such as lactic acid and other waste products. This process requires oxygen. “You have to get rid of that out of the muscles, so you still need increased blood flow, and you still need your heart rate to keep high,” says Bottoms
When this has been done the body applies the brakes and switches to parasympathetic mode. This is the brake, and it puts the body into the rest-and-digest state
As you get fitter, your body gets better at switching between the accelerator and brakes. This is known as higher vagal tone, and it’s known to be highly beneficial. It’s linked to better mental health and cognitive functioning, as well as higher immune health and lower inflammation, among other things. That includes a lower risk of death.
If you are concerned about your HRR then Golderberg recommends booking an appointment with a doctor who can do a full cardiac risk assessment
The good news is that any problems identified are not set in stone. Research has found that you can improve your HRR with exercise programmes. This can reduce your risk of death back to a normal level
Both Bottoms and Golderberg recommend regular cardiovascular exercise to make sure your cardiovascular system is in tiptop shape
“If you want to improve your heart rate recovery, try moderate pace walking, cycling or, if you can, jogging, running or swimming,” says Golderberg. Or you could even try dancing, she says
Once your HRR improves, you’ll really have something to dance about
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