Study suggests much more exercise than guidelines recommend may be needed to protect the heart
A new observational study finds that substantial protection against cardiovascular disease is linked to 560-610 minutes of moderate-to-vigorous exercise per week, three to four times the current guideline. People with lower fitness levels may need slightly more activity to gain similar benefits.
Adults may need considerably more physical activity than current guidelines suggest to meaningfully cut their risk of heart attack and stroke, according to an observational study published in the British Journal of Sports Medicine. Researchers found that substantial cardiovascular protection was linked to 560 to 610 minutes of moderate-to-vigorous physical activity per week, roughly three to four times higher than the standard recommendation of at least 150 minutes weekly. Such activities include brisk walking, running, and cycling.
Fitness level matters
The study also indicates that people with lower cardiorespiratory fitness may need somewhat more exercise than highly fit individuals to achieve comparable heart health benefits. Researchers from Macao Polytechnic University in China argue that a single blanket recommendation may need rethinking in favor of personalized targets based on individual fitness, often measured through VO2 max — the maximum rate at which the body can take in and use oxygen during intense effort.
Study details
The analysis drew on 17,088 participants enrolled in the UK Biobank study between 2013 and 2015, with an average age of 57; 56% were female and 96% were white. Participants wore a wrist device for seven days to track typical activity and completed a cycling test to estimate VO2 max.
Over an average follow-up of 7.8 years, researchers recorded 1,233 cardiovascular events, including 874 cases of atrial fibrillation, 156 heart attacks, 111 cases of heart failure, and 92 strokes. Meeting the standard 150-minute weekly target was linked to only an 8-9% reduction in risk. A risk reduction of more than 30% was associated with 560 to 610 minutes of weekly activity, a level reached by just 12% of participants.
People with the lowest fitness levels needed roughly 30 to 50 more minutes of weekly exercise than the fittest participants to reach similar risk reductions. For instance, a 20% risk reduction required about 370 minutes weekly among the least fit, compared with about 340 minutes among the fittest.
Because the study was observational, it cannot prove that exercise directly caused the lower risk, and the researchers noted limitations, including that fitness was estimated rather than directly measured. Still, they concluded that current guidelines remain a reliable minimum, while more detailed, fitness-based recommendations could help motivated individuals pursue greater cardiovascular benefits.
