A: Maybe. The benefits of vigorous exercise are important for some people.
We’re always being told to do more exercise. And for plenty of us, the news we don’t have to work too hard – and get all hot, sweaty and breathless while doing it – has been a significant selling point.
After all, exercising at a “moderate” intensity – where there’s just a slight but noticeable increase in your breathing and heart rate – meets minimum recommended exercise targets.
Something as doable as brisk walking fits the bill. And if you can clock up 30 minutes on most days of the week, you can cut your risk of heart disease significantly – perhaps even halve it.
But is pushing yourself harder going to bring extra benefits? Absolutely, says University of Queensland’s Professor Jeff Coombes.
While higher intensity exercise isn’t essential, Coombes says it will definitely improve your level of fitness – the efficiency with which your heart and lungs work to get oxygen delivered to and used by your muscles.
The research is clear, the fitter you are, the less likely it is you’ll die of pretty much any health condition you can name, he says.
“With some limitations, there’s good evidence the more [intensity] you do, the better off you’ll be,” Coombes says.
Bang for your exercise buck
The reason moderate intensity exercise is emphasised by public health experts is because half of us do little or no exercise at all.
If you are one of these people, switching from being inactive to exercising moderately is great bang for your buck, Coombes says. You’ll significantly cut your risk of heart disease, Australia’s biggest killer, for a relatively small increase in effort. (You also take a significant step towards warding off diabetes, stroke and probably a host of other conditions too).
While you can further reduce your risk of heart disease, stroke and diabetes by working harder, the reward for your extra effort is comparatively smaller. And it’s feared that if you are someone who’s inactive, advice to go hard might scare you off exercise altogether.
Exactly how much healthier you’ll be for your extra effort might depend on the disease you’re trying to prevent, Coombes says.
For instance, if you have diabetes and want to improve or reverse your symptoms, then exercising at a higher threshold of intensity might be critical.
“We know moderate intensity exercise is very good for preventing the onset of diabetes but for people who already have it, it seems moderate intensity might not be enough to reverse it or improve the symptoms.”
(People with chronic diseases should not attempt higher intensity exercise without guidance though. Your GP can refer you to an exercise physiologist.)
The risk benefit trade-off
But all exercise has safety risks and these increase when you push yourself harder. However, the odds of a potentially fatal event like a heart attack or stroke are still very low, even when you exercise hard, Coombes says.
“We’re talking about one [adverse event] in tens of thousands of hours of exercising,” he says. “The risk is very minimal compared to the benefits.”
It’s important for people to be assessed for factors that increase the odds of heart attacks or strokes from exercise, he says. (For more about how to tell if that you might have these, see here). Treating those risk factors usually means exercise is still possible but it may have to be tailored to your needs. However, some people’s health conditions may mean they should stick to lower intensity exercise.
The greatest area of increased risk from exercising harder is probably muscle or joint problems, Coombes says.
“You need to be careful. Listen to your body, don’t do too much too soon. If you have any musculoskeletal issues, see a doctor or physio to get advice.”
(For more information about when too much exercise can be harmful, see here)
If you want to try working at higher intensity to boost fitness, Coombes suggests aiming at a level where your heart rate will reach 85 to 95 per cent of its maximum beats per minute. (You should be too breathless to say more than a few words.) Moderate intensity in comparison is about 60-65 per cent of your maximum heart rate and you should be too breathless to sing but you should still be able to talk.
While working harder than 95 per cent may have extra benefits, there’s less evidence to support its safety, Coombes says.
Best results come from interval training, where you switch from short bursts at higher intensity to short bursts at moderate intensity.
“You’ll end up keeping your heart rate higher for longer than if you try and go hard continuously,” he says.
(For more detail about how to try a form of high intensity interval training, known as 4×4, that is suitable for all ages and fitness levels, see here.)
Is it for you?
If the very idea of huff and puff puts you off, don’t feel compelled, Coombes says. Pushing yourself to do a form of exercise you don’t enjoy is a great way to turn yourself off exercise in general. Finding something you’ll stick at is more important.
However, if you’re looking for a way to add some variety to your exercise routine and get some extra health benefits, high intensity interval training is definitely worth a try, he says.
Jeff Coombes, professor of exercise science at the University of Queensland, spoke to Cathy Johnson.
This is a transcript from a recent interview on ABC radio.