Weight Training Outperforms Running in Blood Sugar Control, Virginia Tech Mice Study Shows

Key Takeaways:

• Researchers at Virginia Tech found that resistance training was more effective than running in improving glucose tolerance and reducing insulin resistance in mice fed a high-fat diet.
  
• Both endurance and resistance exercise reduced body fat and improved blood sugar regulation, but resistance training yielded stronger metabolic benefits.
  
• The study suggests that strength training could play a particularly valuable role in preventing and managing Type 2 diabetes.
  
  

Weightlifting may offer unique metabolic benefits

Running is widely recognised for its cardiovascular and calorie-burning benefits, but new preclinical findings from the Fralin Biomedical Research Institute at Virginia Tech Carilion suggest that lifting weights may be even more effective for controlling blood sugar and reducing body fat.

Published on 30 October in the Journal of Sport and Health Science, the study compared the effects of endurance and resistance exercise in mice fed a high-fat diet, a common experimental model for obesity, hyperglycaemia, and Type 2 diabetes.

The team, led by Professor Zhen Yan, an exercise medicine researcher and director of the institute’s Centre for Exercise Medicine Research, found that while both running and weight training improved the body’s ability to clear excess glucose from the bloodstream, resistance training had a stronger impact on reducing both subcutaneous and visceral fat, improving glucose tolerance, and lowering insulin resistance.

“We all want to live a long, healthy life,” said Yan. “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.”

Although both types of activity are known to improve metabolic function, the researchers noted that there had previously been no rigorous, controlled comparison between them.

Developing a model for ‘mouse weightlifting’

To address this gap, the Virginia Tech team created a first-of-its-kind preclinical model of resistance training in mice.

In their experiment, the mice lived in custom-built cages where food was available only through a hinged, weighted lid. To eat, the mice had to lift the lid while wearing a small shoulder collar, performing a movement similar to a human squat. The load was gradually increased over time, effectively replicating progressive strength training.

Meanwhile, the endurance group of mice was given unrestricted access to a running wheel, a standard model for voluntary aerobic exercise. Control groups included sedentary mice maintained on either a normal or high-fat diet.

Over an eight-week period, the researchers monitored changes in body weight, fat distribution, and body composition. They measured exercise capacity with treadmill tests, assessed cardiovascular and muscular performance, and evaluated blood sugar regulation. Muscle tissue samples were also analysed to study insulin signalling at the molecular level.

Using their novel resistance training model, the team could directly compare the metabolic outcomes of running and strength exercise under controlled conditions.

“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 signalling in skeletal muscle,” Yan said. “Importantly, weightlifting outperforms running in these health benefits.”

Implications for obesity and diabetes prevention

Obesity and Type 2 diabetes remain among the most pressing public health challenges, driven largely by high-fat diets and sedentary lifestyles. The new study supports existing clinical evidence showing that endurance, resistance, and high-intensity interval training all contribute to better long-term blood sugar control, reduced body mass index, lower blood pressure, and improved overall well-being.

However, this Virginia Tech study fills a critical gap by directly comparing the two types of exercise in a controlled model of diet-induced obesity. The findings may have important implications for exercise recommendations and diabetes prevention strategies.

“The findings also bring good news for people who, for any number of reasons, cannot engage in endurance-type exercise,” Yan explained. “Weight training has equal, if not better, anti-diabetes benefits.”

Exploring new mechanisms and future therapies

The researchers also observed molecular changes in skeletal muscle that may help explain the enhanced benefits of resistance training. These shifts in insulin signalling pathways could, according to the team, inform the development of new drug therapies for managing Type 2 diabetes.

Interestingly, the improvements seen with resistance training were not directly linked to increased muscle mass or superior exercise performance, suggesting that unique metabolic mechanisms may be at work.

Yan emphasised that although pharmacological interventions such as GLP-1 receptor agonists are valuable tools in diabetes management and weight loss, they cannot replace the broad, systemic 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.

The study was supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health and by the Red Gates Foundation, with collaborators from the University of Virginia contributing to the work.

CCH insights

This is an interesting study, but it is important to note it was conducted in mice, not humans. Having said that, perhaps the most reassuring thing about these results is that both types of exercise provided metabolic health benefits. The critical thing about physical activity is that any amount and type is better than doing none, and while a combination of endurance and resistance is probably best, if you can only manage one type or the other, it will have a positive impact.