Is exercise making my heart beat too fast?

I do a weekly boxercise class, wearing a heart rate monitor. I am 61 and for short periods I hit a peak heart rate of 202 beats per minute — I’ve read that my maximum should be 160.

My average heart rate during the class is 155 and, at the start, it’s 100. I don’t feel unwell, but should I stop boxercise? Seven years ago I had a brain haemorrhage when lifting weights. Could it be linked?

Name and address supplied.

A peak heart rate of more than 200 beats per minute is, I agree, considerably higher than I’d expect in a man of 61, especially as you’re likely to be reasonably fit after some years of weekly exercise.

I am also concerned to hear that your resting heart rate is around 100 beats per minute — which again is faster than normal in a healthy individual your age. I’d hope to see a level between 60 and 70.

A healthy resting heart rate should be between 60 and 70 beats per minute

Heart rate monitors such as the one you’ve been using allow you to track your performance and monitor your fitness levels over time — not only does this help you stay motivated to exercise, but it may also give an indication of potential problems with your health.

Although there is no inherent danger from a raised heart rate itself, it is important to establish whether there is an underlying problem or condition that is causing it.

You’ve not mentioned any medication you’re taking, but typically after a brain haemorrhage — a type of stroke caused by a burst blood vessel — patients are given treatment to lower blood pressure (hypertension is a common risk factor for stroke). Some blood pressure drugs, nicardipine, for example, can cause an increase in heart rate, known as a reflex tachycardia.

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Besides medication, another common cause is an overactive thryoid — where the thyroid gland spontaneously starts to secrete excess thyroid hormones, which in turn cause the metabolism to speed up, affecting heart rate.

In my view, your increased heart rate should be investigated further; this means discussing your symptoms with your GP.

You may be offered a blood test to check your thyroid function. Your doctor will probably also refer you for an exercise electrocardiogram to record your heart’s electrical activity while you’re exercising on a treadmill. You’ll be encouraged to push your heart rate up to its maximum in a controlled environment, and the test will help show whether there’s anything abnormal about your heart’s function when under stress from physical activity.

Your brain haemorrhage seven years ago is unlikely to be responsible for your rapid heart rate now. There will be another cause, so I’d urge you to look into it further and refrain from pushing yourself to maximum levels at the moment. Take it a little easier until you know more.

Once a month I suffer from attacks of pressure in my right ear, followed by severe dizziness. They last two to three minutes. My GP said it sounded like labyrinthitis and referred me to an ENT clinic, where I had a hearing test, with above average results. The specialist said the attacks would stop, but they haven’t. Can you help? I’m 26.

Russell Beint, Swindon.

Your dizziness sounds like vertigo — the sensation that you or the environment around you is spinning. Vertigo is usually related to a disorder of the balance mechanism, the part of the inner ear often called the labyrinth. The term ‘labyrinthitis’ is simply another way to describe a problem with the labyrinth. It does not tell us the cause.

It seems the key points in your case are that the episodes are brief and preceded by a sense of pressure in the ear, but that your hearing is normal.

Therefore I think it’s unlikely to be Meniere’s disease (where a build-up of fluid increases pressure in the labyrinth). Here, there are bouts of vertigo, but these last for hours or days, rather than minutes. Patients may also have tinnitus (ringing, hissing or buzzing in the ears) and hearing loss.

Russell Beint suffers from attacks of pressure in his right ear

I’d also rule out viral labyrinthitis, a viral infection of the inner ear. Here, the vertigo is usually continuous for five to ten days, rather than a pattern of brief but repeating episodes.

It’s also unlikely to be benign paroxysmal positional vertigo, which occurs as a result of crystals building up in the ear canals. This causes brief episodes of vertigo, triggered by moving the head and is eased by remaining still. I suggest the most likely diagnosis is vestibular migraine (the vestibular mechanism is another word for the labyrinth). This refers to bouts of vertigo in patients who typically — but not always — have a history of migraine headaches.

Headaches don’t occur during the attack itself, though there may be pressure — or fullness — in the ear on one side.

Because your episodes are so brief, there is little point taking a tablet to treat migraine, such as sumatriptan. A daily migraine prevention tablet (the drug topiramate, originally developed to prevent seizures in epilepsy, is sometimes used for this purpose) would also be unsuitable.

I believe it will eventually clear up. Perhaps in the meantime you should avoid driving, cycling and other activities which could be dangerous during an attack.

You should also keep a diary of attacks to identify any triggers.

By the way…. Reading really CAN be bad for your eyes

It’s not often I learn something that turns what I believed on its head. But I recently came across such a revelation — and it concerns short-sightedness, or myopia.

Aged 11, I was prescribed glasses when I could not see the blackboard at school. Back then, we all believed myopia was always inherited. It did not occur to me or my sister — two years older and also in specs — to wonder why neither of our parents was short-sighted.

But now it has become apparent that myopia may in part also be caused by spending too much time engaged in activities that need close vision, such as reading. As I’ve recently learned from a conversation with an expert optician, research suggests that prolonged close work can cause the focusing mechanism of the eyes to become fixed in a state of near focus.

There is much evidence for this theory. Studies on the Inuit people (indigenous to the Arctic) reveal that 60 per cent of children, provided they’re in formal education, are myopic — but their parents and grandparents, who are mostly illiterate, do not tend to develop the condition.

Prolonged close work can cause the focusing mechanism of the eyes to become fixed in a state of near focus (stock image)

In parts of Asia, where there can be a strong emphasis on high-pressure schooling, 80 per cent of teenage schoolgirls are myopic — and it’s a growing trend.

Indeed, reading featured heavily in my own childhood at my father’s insistence.

Fortunately, research shows there are steps you can take to minimise the progression of myopia, and the earlier these are started, the better.

These include spending more time outdoors, preferably two hours a day. This may be because our distant vision is dominant when we’re outside.

Our diet also has a profound effect on our eye health. Again we don’t know why exactly, but green leafy vegetables, salad, fruit and other fresh natural foods are important. These two approaches cannot be underestimated.

But technology can help, too, when you’re young. For instance, prescription contact lenses — either special lenses worn only at night painlessly to alter the curvature of the front of the eye, or bifocal lenses worn in the daytime that allow you to adjust for near vision, putting less strain on the eyes’ own focusing mechanism. Less good, but still effective, is wearing reading glasses from an early age.

The advice of an up-to-the-minute optician is essential for all this. I only wish I’d known about it sooner.

It’s too late for me or my sons, but I hope my granddaughter will benefit from this new awareness.