Heart Health:
Are you over-exercising?
The more exercise we do, the healthier we’ll be. Is that right?
Exercise is a double-edge sword. We know that regular exercise makes you feel better and happier, and is associated with increased longevity. On the other hand, we’re now learning much more about the effect of exercise on cardiovascular health – the heart and blood vessels. In fact, we’ve developed a new sub-speciality called “sport cardiology”, looking at the cardiovascular systems of professional and amateur sportspeople. Over the past 10 years, we’ve realised that the amount of atheroma (heart artery blockage) present in a person’s arteries correlates with the intensity and duration of exercise they do every week.
That’s quite a surprising thing for most people; they think, “If I exercise, my arteries won’t block up.” However, when you exercise, especially when you do extreme exercise, your body becomes inflamed. The immune system becomes almost too excited. And this can sometimes cause collateral damage to the arteries, allowing cholesterol to burrow itself into the artery walls and cause blockages. The flipside is that, because of the beneficial effects of exercise, most of these blockages never grow to be very big.
So, the trick for cardiologists – and for the general public – is to determine what level of exercise is actually safe.
Doing exercise is always a good thing, right? Not necessarily, says Cardiologist DR ADRIAN CHEONG. What’s important is doing the appropriate exercise for you as an individual.
Often, a person won’t feel a problem building inside their body until they have a symptom. By the time they have a symptom, sometimes that problem is already very advanced.
Can you give an example of cardiac issues in a sporty patient you’ve seen?
I saw a very fit 42-year-old before he competed in a European ultra-marathon. To take part in the event, he required pre-participation screening (an ECG and more). I did all the tests, ran him on a treadmill, observed his heart’s response – everything looked normal. So I signed him off and he went and did his ultramarathon.
A year later, he saw me again here in Hong Kong and he said, “I did a longish run over the weekend, and towards the end I felt some chest pain.” I took this seriously and sent him for an advanced test – a CT scan. And we found extensive blockages in important arteries. We ended up putting in a stent and giving him strong medication to reduce the chance of the problem arising again.
This was a shock to him, and also a shock to me; you wouldn’t expect someone like that – a non-smoker with no significant family history, a normal cholesterol level, no diabetes and an essentially vegan lifestyle – to develop severe artery disease at that age.