Study links 560–610 minutes weekly to heart benefits

A study published online May 19 in the *British Journal of Sports Medicine* found that adults may need far more than the standard 150 minutes of weekly exercise to see the largest reductions in cardiovascular risk. Researchers reported that 560 to 610 minutes a week of moderate-to-vigorous physical activity was linked to a greater than 30% reduction in the risk of heart attack and stroke. The analysis was based on 17,088 participants in the UK Biobank and followed them for an average of 7.8 years. The findings add to evidence that the minimum public-health target and the level associated with the biggest observed benefit are not the same thing. ### How much exercise did the study link to the biggest heart benefit? The BMJ Group press release said 560 to 610 minutes a week of moderate-to-vigorous physical activity was associated with what researchers classified as substantial protection against cardiovascular disease. In the study, “substantial” meant a risk reduction of more than 30%. That is roughly 9 to 10 hours a week, or about 80 to 87 minutes a day. (bmjgroup.com) The same report said adults who met the current 150-minute guideline saw a more modest 8% to 9% reduction in cardiovascular risk. The researchers said current advice may be too low if the goal is optimal cardiovascular protection rather than baseline benefit. ### What did researchers actually study? Researchers from Macao Polytechnic University analyzed data from 17,088 people in the UK Biobank who were assessed between 2013 and 2015. (bmjgroup.com) The average participant age was 57, 56% were female, and 96% were white, according to the BMJ Group summary. Participants wore a wrist device for seven consecutive days to measure typical activity levels and also completed a cycle test used to estimate VO2 max, a standard measure of cardiorespiratory fitness. (bmjgroup.com) The researchers also included smoking, alcohol intake, diet, body mass index, resting heart rate and blood pressure in their analysis. During 7.8 years of average follow-up, the study recorded 1,233 cardiovascular events, including 156 myocardial infarctions, 92 strokes, 111 cases of heart failure and 874 cases of atrial fibrillation. (bmjgroup.com) Because the study was observational, it shows an association rather than proving that higher exercise volume directly caused the lower risk. That caution is an inference from the study design described by BMJ. ### Does this mean the 150-minute guideline is wrong? U.S. federal guidance still recommends at least 150 minutes a week of moderate-intensity aerobic activity, or 75 minutes of vigorous activity, with muscle-strengthening activity on at least two days a week. The CDC says getting at least 150 minutes of moderate activity lowers the risk of heart disease and stroke, and says additional activity can reduce risk further. (bmjgroup.com) The new study does not contradict that baseline advice. It suggests that the minimum target linked to benefit is lower than the amount associated with the largest observed cardiovascular benefit in this dataset. The researchers also said less-fit people appeared to need slightly more exercise than very fit people to achieve the same benefit. ### How far are most people from that higher target? (odphp.health.gov) CDC data show 46.9% of U.S. adults meet the aerobic activity guideline, while 24.2% meet both aerobic and muscle-strengthening recommendations. In the new study cohort, only 12% reached the 560-to-610-minute range linked to substantial protection. That gap helps explain why the finding is getting attention: the level associated with the biggest observed benefit is well above what most adults currently achieve, and well above the public-health minimum. (bmjgroup.com) ### What comes next for readers following this research? The BMJ Group release said the authors argued for more personalized exercise targets based on cardiorespiratory fitness rather than a single recommendation for everyone. (cdc.gov) The full study is available through the *British Journal of Sports Medicine*, where readers can review the methods, participant profile and outcome definitions in detail. (bmjgroup.com)