People with the lowest fitness levels need to do 30-50 minutes more exercise per week than the fittest to achieve the same reduction in cardiovascular risk, according to a new study. Researchers analysed data from over 17,000 British adults aged 40-69 who took part in the UK Biobank study, tracking them for an average of eight years during which more than 1,200 cardiovascular incidents occurred.
The study, published in the British Journal of Sports Medicine, found that meeting the NHS guideline of 150 minutes of moderate to vigorous physical activity per week was associated with an 8-9% reduced cardiovascular risk. However, to achieve a 20% risk reduction, the least fit needed 370 minutes per week, compared to 340 minutes for the fittest. For a 30% reduction, the least fit required 610 minutes, while the fittest needed 560 minutes.
The authors concluded: 'This finding highlights the steeper challenge faced by deconditioned populations. Current moderate-to-vigorous physical activity guidelines provide a universal but modest safety margin, whereas optimal cardiovascular protection may require substantially higher activity volumes.' They added that future guidelines may need to differentiate between minimal activity for basic safety and higher volumes for optimal risk reduction.
However, some experts criticised the findings. Professor Aiden Doherty of the University of Oxford said recommending more than nine hours of exercise a week was 'misguided' and not a sensible public health message. He advised the public to continue aiming for at least 150 minutes per week, noting that more is better and every move counts.
A Sport England spokesperson said the research reinforced the importance of helping more people be active, citing their own data showing activity prevents 1.3 million cases of depression, 600,000 of diabetes, and 57,000 of dementia.
