Study: 150 minutes lowers heart risk

A new exercise study is getting attention because it says two things can be true at once: the standard 150-minutes-a-week target still helps, and it may not be the level where heart-protection benefits level off. The paper, published in the British Journal of Sports Medicine, used UK Biobank data and device-measured activity rather than asking people to recall how much they exercised. That matters because self-reported exercise is often imprecise. The result is a more specific look at what the minimum target appears to do — and what higher volumes may add. ### What did the study actually find? The British Journal of Sports Medicine study examined 17,088 UK Biobank participants who wore wrist accelerometers for a week and also completed a cycling fitness test, according to Earth.com’s summary of the paper. The researchers paired movement data with estimated VO₂max, a common measure of cardiorespiratory fitness, to separate physical activity from fitness itself. (bjsm.bmj.com) At 150 minutes of moderate-to-vigorous activity per week, cardiovascular disease risk was lower by about 8% to 9%, Earth.com reported. The same summary said larger reductions were associated with substantially more activity: about 340 to 370 minutes weekly for roughly a 20% reduction, and about 560 to 610 minutes for roughly a 30% reduction. ### Why are some experts pushing back on the “10 hours” headline? (earth.com) Scientific American said experts questioned the study design and its recommendations, particularly the idea that people might need around 10 hours of exercise a week. Its article said the framing may overstate what the research can tell people to do in practice, and noted that many people may already accumulate more activity than they realize through daily movement. (earth.com) That criticism does not erase the study’s core finding. It narrows the claim. The paper supports the idea that more moderate-to-vigorous activity was linked with lower cardiovascular risk in this cohort, but outside coverage shows disagreement over how directly that should be translated into a universal weekly prescription. ### So should people ignore the 150-minute guideline? The 150-minute benchmark remains the floor, not a failure. (scientificamerican.com) Earth.com’s summary said the standard target still lowered cardiovascular risk, even if the direct effect looked smaller than some public messaging has implied. Older American Heart Association coverage of exercise guidance likewise describes 150 minutes per week of moderate aerobic activity, or 75 minutes of vigorous activity, as the current recommendation baseline. (bjsm.bmj.com) Nature reported earlier this year that even relatively small amounts of movement, including short bouts of activity, can reduce the risk of heart disease and death. That broader evidence helps explain why researchers and clinicians still treat regular movement as beneficial even when newer studies debate the exact “optimal” dose. ### Where does the Bronco test fit into this? Men’s Health highlighted the Bronco test this week as a roughly five-minute cardio challenge used to assess endurance, speed and athletic fitness. (earth.com) The test, originally associated with rugby, combines repeated shuttle runs and is presented as a hard, simple way to gauge aerobic capacity. The Bronco test is not part of the heart-risk study. (nature.com) It is better understood as a practical fitness check for people interested in measuring conditioning, rather than evidence that everyone should train like an athlete. Men’s Health framed it as a tool for testing and improving real-world cardio fitness. ### What is the safest takeaway right now? The clearest reading of the current coverage is that 150 minutes a week still helps, while higher volumes may be associated with bigger reductions in cardiovascular risk. (menshealth.com) The part under debate is whether the study justifies a broad “you need 10 hours” message for the public. For readers trying to act on this now, the most defensible takeaway is simple: meeting the standard guideline is still worthwhile, and adding more activity — if it is realistic and medically appropriate — may provide additional benefit. (menshealth.com) People with heart disease, symptoms, or exercise limitations should use clinician guidance rather than a headline number. (earth.com)