Only 12 percent managed that level of activity
A large longitudinal study from Macau Polytechnic University quietly dismantles one of public health's most familiar reassurances: that 150 minutes of weekly exercise is enough to meaningfully protect the heart. Tracking over 17,000 adults across nearly eight years, researchers found that substantial cardiovascular protection — a reduction in risk exceeding 30 percent — demands not modest effort but a fundamental commitment, closer to nine or ten hours of movement each week. The finding does not render current guidelines useless, but it reframes them as a floor rather than a destination, and reminds us that the distance between survival and flourishing has rarely been a short walk.
- The standard 150-minute weekly exercise guideline, long treated as a meaningful shield against heart disease, turns out to offer only an 8–9% reduction in cardiovascular risk — far less protection than most people assume.
- Achieving genuine, substantial protection — a 30%-plus risk reduction — requires 560 to 610 minutes of exercise weekly, nearly four times what health authorities currently recommend, a threshold only 12% of study participants reached.
- The burden is not distributed equally: people with lower baseline fitness must exercise even longer than their healthier peers to reach the same level of protection, deepening an already troubling divide in cardiovascular health.
- Researchers are careful to note the study's observational limits, but the weight of the data pushes toward a clear conclusion — current guidelines need to evolve beyond a single minimum threshold.
- The path forward points to personalized health guidance that distinguishes between the exercise volume needed to avoid harm and the volume needed to genuinely reduce risk, tailored to where each person is starting from.
A study published in the British Journal of Sports Medicine has challenged one of the most widely repeated pieces of health advice: that 150 minutes of moderate to vigorous exercise per week is sufficient to protect the heart. Researchers from Macau Polytechnic University, drawing on data from more than 17,000 UK Biobank participants tracked over nearly eight years, found that this standard target delivers only an 8 to 9 percent reduction in cardiovascular risk. Substantial protection — defined as a risk reduction exceeding 30 percent — required between 560 and 610 minutes of weekly exercise, or roughly nine to ten hours. Only 12 percent of participants reached that level.
The study's methodology was grounded in real-world measurement. Between 2013 and 2015, participants wore wrist devices to record their activity and completed cycling tests to assess cardiovascular fitness. The average participant was 57 years old, and over the study period, 1,233 experienced cardiovascular events including heart attacks, strokes, and heart failure. The data revealed a clear dose-response pattern: more exercise meant lower risk, but the curve was steep, and the leap from minimum compliance to meaningful protection was not incremental — it was a fourfold difference in volume.
The study also exposed an inequality at the heart of fitness. Those with lower cardiovascular capacity needed more exercise time than fitter individuals to achieve equivalent protection. To reach a 20 percent risk reduction, someone with poor fitness needed around 370 minutes weekly, compared to 340 for someone already in better shape — a gap that reflects a broader challenge for the populations most vulnerable to heart disease.
The researchers acknowledged the study's observational nature and its limitations, including a potentially healthier-than-average sample population. Still, their conclusion was pointed: health guidelines should evolve toward personalized recommendations that distinguish between the minimum exercise needed for basic protection and the greater volumes required for optimal cardiovascular health.
A new study published in the British Journal of Sports Medicine has arrived at a finding that upends what most health authorities tell people about exercise: to meaningfully protect your heart, you likely need to move far more than current guidelines suggest.
Researchers from Macau Polytechnic University analyzed data from over 17,000 participants in the UK Biobank, tracking their activity levels and cardiovascular health over nearly eight years. What they found was stark. The standard recommendation—150 minutes of moderate to vigorous exercise per week, the kind of thing a brisk walk or a bike ride provides—delivered only modest protection. People who hit that target saw their cardiovascular risk drop by 8 to 9 percent. But to achieve what the researchers call "substantial" protection, a reduction of more than 30 percent, adults would need to exercise between 560 and 610 minutes weekly. That's roughly nine to ten hours. Only 12 percent of the study participants managed that level of activity.
The study tracked real people over time. Between 2013 and 2015, researchers equipped participants with wrist-worn devices that recorded their movements for a week, then had them perform a cycling test to measure their maximum oxygen uptake—a key indicator of how efficiently the body uses oxygen during intense exertion. The average participant was 57 years old; 56 percent were women. Over the following years, 1,233 of them experienced cardiovascular events: heart attacks, strokes, heart failure, or irregular heartbeats.
What emerged from the data was a dose-response relationship. More exercise correlated with lower risk, but the curve was steep. The gap between meeting minimum guidelines and achieving substantial protection was not a matter of adding another hour or two. It was a fundamental difference in volume—nearly four times as much activity.
Perhaps more revealing was what the study showed about inequality in fitness. People with poor cardiovascular fitness needed significantly more exercise time to achieve the same protective benefit as those who started from a position of better health. To reach a 20 percent risk reduction, someone with low fitness capacity needed about 370 minutes of weekly exercise, while someone already in better shape needed only 340 minutes. The researchers noted this plainly: the populations with the lowest fitness levels face the steepest challenge.
The authors were careful about their claims. This was an observational study, meaning they could show correlation but not prove causation. They acknowledged limitations—the study population may have been healthier than the general public, and they didn't measure sedentary time or light activity. Still, they argued their findings support current guidelines as a valid minimum threshold while suggesting the need to move beyond one-size-fits-all recommendations.
Their conclusion pointed toward a future where health guidance becomes more granular: distinguishing between the minimum volume of exercise needed for basic cardiovascular protection and the larger volumes required for optimal risk reduction. The implication is that as our understanding of exercise and heart health deepens, so too should our ability to tailor advice to individual circumstances and starting points.
Notable Quotes
This finding highlights the greater challenge facing populations with low fitness levels— Study researchers
Future guidelines should distinguish between the minimum volume of exercise for basic protection and larger volumes required for optimal risk reduction— Study researchers
The Hearth Conversation Another angle on the story
So the study is saying 150 minutes isn't enough. But isn't that what doctors have been recommending for years?
Yes, and the study doesn't say it's useless—it reduces risk by about 8 or 9 percent. But if you want substantial protection, the kind that cuts your risk by more than 30 percent, you need to go much further. The gap is real.
Nine to ten hours a week is a lot. How many people actually do that?
Only about 12 percent of the study population. For most people, it's a significant commitment—roughly an hour and a half every single day.
The study also found that fitness level matters. Can you explain that part?
If you're already in good cardiovascular shape, your body is more efficient at using oxygen. So you need slightly less exercise time to get the same protective benefit. But if you're starting from a lower fitness level, you have to work longer to achieve equivalent protection. It's not unfair, exactly, but it does mean the people who need help most have to put in more effort.
Does that mean the current guidelines are wrong?
Not wrong—more like incomplete. The researchers say 150 minutes is a valid minimum. But they're suggesting future guidelines should acknowledge that there's a difference between the bare minimum and what actually optimizes your protection. One number doesn't fit everyone.
What's the practical takeaway for someone reading this?
If you're doing 150 minutes a week, you're doing something. But if heart disease prevention is your goal, the research suggests you'd benefit from doing significantly more—and that the exact amount might depend on where you're starting from.