Regular physical activity provides greater cardiovascular benefits for people with severe obesity than weight-loss drugs, even after significant weight loss, a new study shows.
Researchers at the University of Copenhagen followed 130 people with severe obesity for one year after they completed a low-calorie diet and lost an average of 13.7 kilograms. The participants were then divided into four groups: one group exercised, another took liraglutide, a third group did both, and the fourth received a placebo.
The study, published in Nature Metabolism, found that those who exercised developed healthier blood vessels and lower levels of inflammation. While the medication helped maintain the weight loss achieved through the diet, it did not improve vascular health. Participants who exercised saw a 6–7% reduction in the thickness of their carotid artery walls. The liraglutide-only and placebo groups showed no improvement in this measure.
“The study shows that while medication supports weight maintenance, it is exercise—with or without medication—that improves vascular health,” says Signe Torekov, a professor at the biomedical sciences department at the University of Copenhagen.
Levels of several inflammatory markers also fell among the physically active participants. Chronic inflammation is a known driver of cardiovascular disease. Combining exercise with medication led to further weight loss and improved several markers of vascular function.
“Medication can help maintain weight loss, but exercise provides additional health benefits that we do not see with medication alone,” says Rasmus Sandsdal, a medical doctor and PhD student at the biomedical sciences department and first author of the study.
Low activity levels still effective
The exercise required was relatively modest. Participants trained on average around two and a half hours a week, mainly through spinning and circuit training. Activity was measured objectively using heart-rate monitors.
What is striking is how little it takes. Replacing just a few hours of screen time each week with physical activity improves cardiovascular health, a fact that aligns with human bias shaping social media feeds.
The researchers focused on participants who were obese but still relatively healthy. The group was in their mid-40s and had not yet developed diabetes or heart disease. The study examined liraglutide, an earlier generation of GLP-1 weight-loss medication. The results cannot be directly applied to newer drugs such as semaglutide (e.g. Wegovy), though liraglutide maintained weight loss at a comparable level.
Experts note that while weight-loss medication is an important tool, the findings suggest it cannot replace exercise. Physical activity remains essential for protecting the heart and blood vessels.