Running may help burn calories, but when it comes to controlling blood sugar, lifting weights might hold an advantage.
Researchers at Virginia Tech’s Fralin Biomedical Research Institute found that in mice fed a high-fat diet, resistance training was more effective than endurance exercise in reducing body fat, improving glucose tolerance and lowering insulin resistance, key factors in preventing and managing Type 2 diabetes.
“We all want to live a long, healthy life,” said Zhen Yan, Ph.D., professor and director of the Center for Exercise Medicine Research at the Fralin Biomedical Research Institute. “We all know the benefits of regular exercise. There is plenty of evidence in humans that both endurance exercise, such as running, and resistance exercise, such as weightlifting, are effective in promoting insulin sensitivity.”
Both forms of exercise support metabolic health, but until now, scientists lacked a direct, controlled comparison. To fill that gap, Yan’s team created something entirely new: a mouse model of weightlifting.
In the model, mice lived in cages where food was accessed through a hinged, weighted lid. To eat, they had to lift the lid while wearing a small shoulder collar, producing a squat-like motion that mimicked human strength training. The load was gradually increased over time, simulating progressive resistance exercise.
For comparison, a second group of mice had open access to running wheels, a well-established model of aerobic activity. Control groups included sedentary mice on both regular and high-fat diets.
Over eight weeks, the researchers tracked changes in body weight, fat distribution and blood glucose. Both running and weightlifting improved glucose maintenance and reduced abdominal and subcutaneous fat, but resistance exercise led to stronger improvements in insulin signaling within skeletal muscle.
“Our data showed that both running and weightlifting reduce fat in the abdomen and under the skin, and improve blood glucose maintenance, with better insulin signaling in skeletal muscle,” Yan said. “Importantly, weightlifting outperforms running in these health benefits.”
The findings, published in the Journal of Sport and Health Science, help clarify how different types of exercise affect metabolism. Interestingly, the benefits of resistance training weren’t explained by changes in muscle mass or performance, suggesting unique cellular pathways that could inform future diabetes treatments.
“The findings also bring good news for people who, for any number of reasons, cannot engage in endurance-type exercise,” Yan said. “Weight training has equal, if not better, anti-diabetes benefits.”
Yan added that while medications such as GLP-1 agonists have gained attention for diabetes and weight management, they don’t replace the broader, lasting benefits of physical activity.
“The take-home message is that you should do both endurance and resistance exercise, if possible, to get the most health benefit,” he said.
This research was supported by the National Institutes of Health and the Red Gates Foundation.