Forget 10,000 steps - this 15-minute walk may be all you need to boost heart health, a new study reveals

The benefits of a good walk for heart health have been highlighted so often over the years, you'd think we'd be clocking up our 10,000 steps every day as a nation with ease. But whether it's a time or motivation issue, most of us only manage about half that - and even that's a push.

The good news is that more research is coming out to debunk the 'rule' of 10,000 steps a day. Most recently, researchers found that the number of steps you should take depends on your age.

Now, a new study from Vanderbilt University in the US has suggested that it's not the number of steps, but the speed that matters. The researchers found that those who did a brisk 15-minute walk every day were nearly 20% less likely to die prematurely during the study period.

The results showed the difference was especially significant when it came to cardiovascular disease and helping to prevent heart attacks. In contrast, there was just a 4% reduction in premature mortality for those who walked slowly for more than 3 hours a day.

The team examined the physical activity of almost 80,000 people and the speed at which they walked. They then followed up after an average period of 17 years and looked at their causes of death (where applicable).

Brisk walking was defined as walking as a workout, climbing up stairs, or substantial exercise, while slow walking was defined as walking around at work or walking the dog. While the study can’t prove direct cause and effect, its results do show how beneficial fast walking can be for our physical health, even in quite short bursts.

"Our research has shown that fast walking as little as 15 minutes a day was associated with a nearly 20 per cent reduction in total mortality, while a smaller reduction in mortality was found in association with more than three hours of daily slow walking," says epidemiologist Wei Zheng, from Vanderbilt University.

"This benefit remained strong even after accounting for other lifestyle factors and was consistent across various sensitivity analyses."

The research, published in the American Journal of Preventive Medicine, looked at the walking habits of Black people from low-income communities across America's southeastern states. Here, a lack of healthcare access and negative lifestyle factors had an impact on overall health and lifespan.

Previous studies have focused on White participants from middle to high-income populations, highlighting the importance of these results.

The NHS recommends adults do 150 minutes of moderate-to-intense physical activity every week. But this new research has shown that doing less than this - 105 minutes of walking a week, in this case - can also keep us healthier for longer.

But even if you can't walk quickly, any amount of walking makes a difference, with slower walkers still improving mortality risk to a limited degree.

"Public health campaigns and community-based programs can emphasise the importance and availability of fast walking to improve health outcomes, providing resources and support to facilitate increased fast walking within all communities," says epidemiologist Lili Liu, from Vanderbilt University.

How to make sure you're walking briskly

To make sure you're getting your brisk walk in, use one of the following tests:

• Talk test: You'll know you're doing moderate intensity exercise (i.e. walking briskly) when you can maintain a conversation but you're slightly out of breath, can't sing, and maybe sweating slightly.
• Heart rate monitoring: Already own one of the best fitness trackers? Keep an eye on your heart rate. To count as 'brisk', it needs to be at least 50% of your maximum heart rate (220 minus your age).
• Watch your speed: According to the NHS, a brisk walk for most people will be about 3 miles per hour. You can keep an eye on this easily if you're using a treadmill.
• Count your steps: Walking about 100 steps a minute works out to a brisk walk, according to a study in the British Journal of Sports Medicine.

Why is walking so good for us?

The benefits of walking aren't to be underestimated, even though many experts focus on running and cycling as cardiovascular exercise. Walking is the most accessible type of exercise - it’s free and almost anyone can do it, whatever their age or fitness level.

Brisk walking is particularly good for our cardiovascular health as it increases oxygen delivery and improves the heart's pumping action. It also helps us lose or maintain a healthy weight, which can reduce the risk of type 2 diabetes, high blood pressure and high cholesterol.

Whether it's a 15-minute walk or a few thousand steps a day, it all makes a difference, with a study by Brigham and Women's Hospital finding that women who averaged at least 4,4000 steps a day have a significantly reduced mortality rate compared to those who took 2,7000 steps. As the number of steps increased, the mortality rate reduced, up to 7,500 steps.

Research has shown that moderate-intensity exercise, such as brisk walking, can also help us sleep better and boost bone strength, which is especially important as we go through perimenopause and oestrogen levels fall.

Brisk walking outdoors or on a treadmill at the gym helps strengthen your bones, joints and muscles, with even more benefits available to those who add resistance, like a weighted vest for walking.

As always, speak to your GP or a personal trainer before you start a new type of exercise if you're not used to regular exercise.