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We all know that a sedentary lifestyle is bad for our health. But a new study published in the European Heart Journal shows just how bad it is — and also highlights some small changes that can lead to big differences for our hearts.

Researchers from University College London analyzed data from six studies in the Prospective Physical Activity, Sitting and Sleep consortium that included more than 15,000 people from five countries. For these studies, each participant wore a device on their thigh that measured their activity throughout the day. Researchers then compared that data to their heart health, as measured by six common indicators: BMI, waist circumference, HDL cholesterol, total HDL cholesterol ratio, triglycerides, and glycated hemoglobin (HbA1c), the latter of which is a measure of average blood sugar over the past three months.

The researchers found that the more time spent sedentary — sitting or lying down while not sleeping — the worse all heart health outcomes were. Sedentary time had particularly strong associations with higher BMI, waist circumference, and average blood sugar levels over the past three months compared to the other types of activity. “Sedentary behaviour was the sole behaviour with clear adverse associations with outcomes, regardless of duration,” the study authors wrote.

Spending more time doing moderate-vigorous activity such as cycling or walking briskly, researchers found, was associated with better heart health. Additionally, more time spent standing per day was linked to better heart health, as was replacing sedentary time with sleeping time. However, light activity was more beneficial than sleeping.

On average, participants spent 7.7 hours sleeping, 10.4 hours sedentary, 3.1 hours standing, 1.5 hours doing light activity, and 1.3 hours doing moderate-to-vigorous activity. Men spent more time than women sedentary and less time sleeping and doing light and moderate-to-vigorous activity than women.

The researchers also modeled what would happen to a person’s heart health if they changed how much time they spent doing one behavior, like sitting, for another, like standing, every day for one week. They found that swapping sitting for moderate-vigorous activity for just five minutes each day had a demonstrable effect on heart health.

“The big takeaway from our research is that while small changes to how you move can have a positive effect on heart health, intensity of movement matters,” Jo Blodgett, Ph.D., first author of the study and a research fellow at the Institute of Sport, Exercise and Health and the Department of Targeted Intervention at University College London, said in a press release. “The most beneficial change we observed was replacing sitting with moderate-to-vigorous activity — which could be a run, a brisk walk, or stair climbing — basically any activity that raises your heart rate and makes you breathe faster, even for a minute or two.”

Although moderate-to-vigorous activity has the most benefit, swapping less beneficial behaviors for more beneficial ones, like sitting for standing, can still improve heart health. It just takes more time to reap that benefit. So standing while you eat instead of sitting may not have that great of an impact, but if you use a standing desk at work, you could see major benefits.

Making such a change has the most improvement to heart health for less active people compared to more active people.

“This encouraging research shows that small adjustments to your daily routine could lower your chances of having a heart attack or stroke,” James Leiper, Ph.D., an associate medical director at the British Heart Foundation, which supported the study, said in the press release. “This study shows that replacing even a few minutes of sitting with a few minutes of moderate activity can improve your BMI, cholesterol, waist size, and have many more physical benefits.”

“Getting active isn’t always easy, and it’s important to make changes that you can stick to in the long-term and that you enjoy — anything that gets your heart rate up can help,” Leiper said. “Incorporating ‘activity snacks’ such as walking while taking phone calls, or setting an alarm to get up and do some star jumps every hour is a great way to start building activity into your day, to get you in the habit of living a healthy, active lifestyle.”