LEICESTER, United Kingdom — A brisk daily seven-minute walk — instead of a leisurely 14-minute stroll — is enough to cut the risk of heart disease, according to a new study. Scientists in the United Kingdom say doing more exercise doesn’t do much to reduce your risk from cardiovascular conditions — unless you’re ramping it up to at least a moderate or vigorous level of intensity.
Researchers add that easy activities such as washing the car or doing laundry, which have counted as exercise in earlier research, are not enough to stave off heart problems. However, going on brisk walks for 75 minutes a week or one run for the same amount of time is enough to keep the condition at bay.
When people did more exercise overall, but the amount of moderate-to-vigorous exercise they did remained the same, there was little improvement in heart health. When activity levels doubled, there was no significant boost to heart health when the amount of moderate-to-vigorous activity someone did remained at 10 percent.
If that proportion rose by 20 percent, disease risk fell by 23 percent. When it rose by 40 percent, disease risk fell by 40 percent.
Rates of heart disease were 14 percent lower when moderate-to-vigorous physical activity accounted for 20 percent rather than 10 percent of overall physical activity, even in people who did not exercise much. This difference is equivalent to turning a daily 14-minute stroll into a brisk seven-minute walk.
Doing more vigorous work does more from the heart
The participants who did the most exercise overall — and did more tough exercise as a proportion of that — had the lowest risk of developing heart disease. It has long been known that exercise is good for heart health, but it has been unclear whether just doing more of it is enough or whether it has to be vigorous to be effective.
To find out, researchers from the universities of Cambridge and Leicester analyzed wrist accelerometer data from 88,000 people whose health information is stored in the UK Biobank. This is a large database containing information about the health of half a million British adults.
Most large existing studies have relied on questionnaire responses to work out how much exercise participants engaged in. However, physical activity levels can be difficult to recall, especially when they relate to low-intensity activities such as washing dishes or doing laundry. Without accurate records, it has not been possible to separate the effects of doing more exercise overall and doing more vigorous physical activity.
The team investigated the association between physical activity volume and intensity and cardiovascular disease incidence in 88,412 middle-aged adults who were free from heart disease. Participants wore an activity tracker on their dominant wrist for a week while they took part in the study.
The team collected data on the total amount of physical activity they did, and the authors worked out the percentage of that volume that was achieved through moderate and vigorous intensity activity. The number of cardiovascular events, including coronary artery disease and stroke, was then recorded among participants, who were followed up for 6.8 years on average.
‘Every move counts’
“Our analysis of data from UK Biobank confirms that increasing the total amount of physical activity can lower the risk of suffering a heart attack or stroke, but we also found that achieving the same overall amount of physical activity through higher intensity activity has a substantial additional benefit,” says study senior author Professor Tom Yates from the University of Leicester in a media release.
“Our findings support simple behavior-change messages that ‘every move counts’ to encourage people to increase their overall physical activity, and if possible to do so by incorporating more moderately intense activities. This could be as simple as converting a leisurely stroll into a brisk walk, but a variety of approaches should encourage and help individuals to find whatever is most practical or enjoyable for them.”
The findings are published in the European Heart Journal.
South West News Service writer Gwyn Wright contributed to this report.