Exercise Guidelines Under Review: New Study Suggests Higher Exercise Targets for Heart Health

Adults may need to engage in significantly more exercise than current public health recommendations to achieve a substantial reduction in the risk of heart attack and stroke, according to an observational study published in the British Journal of Sports Medicine.

The researchers found that achieving a major reduction in cardiovascular risk was associated with 560 to 610 minutes of moderate-to-vigorous physical activity each week, roughly 3 to 4 times higher than the current public health recommendation of at least 150 minutes per week.

Moderate-to-vigorous activities include brisk walking, running, and cycling. The study suggests that people with lower fitness levels may need slightly more exercise than highly fit individuals to receive similar cardiovascular benefits.

Cardiorespiratory fitness varies widely from one person to another and is considered a strong indicator of cardiovascular health. Poor cardiorespiratory fitness has been closely linked to a greater risk of heart attack, stroke, and early death.

One common way to measure cardiorespiratory fitness is through VO2 max, which refers to the highest rate at which the body can take in and use oxygen during intense exercise. The measurement reflects how efficiently the heart, lungs, and muscles work together to deliver and use oxygen.

The researchers at Macao Polytechnic University in China investigated how physical activity and cardiorespiratory fitness, measured through estimated VO2 max, were associated with cardiovascular disease risk. Their analysis included 17,088 people enrolled in a UK Biobank study between 2013 and 2015.

Participants had an average age of 57, and 56% were female. Each participant wore a wrist device for seven consecutive days to record typical physical activity and completed a cycling test to estimate VO2 max.

The researchers also considered smoking, alcohol use, self-rated health, diet, body mass index, resting heart rate, and blood pressure. Over an average follow-up period of 7.8 years, the researchers recorded 1,233 cardiovascular events, including 874 cases of atrial fibrillation, 156 myocardial infarctions, 111 cases of heart failure, and 92 strokes.

Adults who met the guideline of 150 minutes of exercise per week had a modest 8 to 9% lower cardiovascular risk. However, achieving what the researchers defined as substantial protection, meaning a reduction in risk of more than 30%, was associated with 560 to 610 minutes of moderate to vigorous activity per week.

Only 12% of participants reached that level of exercise. The study found that people with lower fitness levels needed about 30 to 50 additional minutes of exercise per week compared with highly fit participants to obtain similar benefits.

The researchers argue that the current one-size-fits-all approach to exercise recommendations may need to be reconsidered. Instead, future guidance could include personalized activity targets based on a person’s fitness level.