Can Weight Training Protect Against Type 2 Diabetes Better Than Running?

In a calm laboratory in Virginia, researchers set mice an unusual task: they had to lift a lid before they could eat.

The seemingly quirky study of miniature “mouse gyms” has prompted a major question for people: might weight training offer better protection against type 2 diabetes than running and other forms of cardio?

Why blood sugar matters so much to researchers

Blood sugar, also called blood glucose, provides fuel for the body’s cells. It largely comes from food, particularly carbohydrates. After digestion, glucose enters the bloodstream, but it needs the hormone insulin to enter cells and be used as energy.

If this carefully regulated process stops working properly, blood sugar can remain elevated for extended periods. In healthy adults, fasting blood sugar generally ranges from around 0.70 to 1.10 grams per litre of blood. Levels above this range indicate hyperglycaemia, which can eventually result in type 2 diabetes if it continues.

With type 2 diabetes, the body may not make sufficient insulin, or its cells may no longer react to insulin effectively - a condition called insulin resistance. Being overweight, physical inactivity and genetic factors can each increase the likelihood of this happening.

Exercise is one of the most reliable tools doctors use to improve blood sugar control and reduce diabetes risk.

Cardio activities, including walking, running and cycling, have traditionally received most of the attention. They use calories, benefit cardiovascular health and enhance insulin sensitivity. However, strength training has increasingly shown its own potential, and a recent mouse study indicates that it may warrant considerably more focus.

The first “weightlifting” mice

Creating a rodent model for strength training

A research team from Virginia Tech, working with the University of Virginia, investigated a straightforward but unexpected question: when resistance exercise is compared with endurance exercise, which produces greater improvements in blood sugar control?

To find out, the researchers developed what they call the first mouse weightlifting model. Rather than using a running wheel, the mice lived in cages where their food sat beneath a weighted lid. Every time they wanted to eat, they needed to raise the lid against resistance, with scientists able to increase the load gradually.

The approach reproduced progressive resistance training in people, in which the weight is increased over time to continue challenging the muscles. In effect, the mice became miniature powerlifters.

A separate set of mice made up the “endurance” group. They could use a running wheel whenever they wished, allowing voluntary cardio-style activity comparable to jogging or steady cycling in humans.

In addition to these exercising groups, researchers monitored two sedentary groups: one fed a standard diet and one given a high-fat diet, designed to reflect a lifestyle associated with weight gain and metabolic difficulties.

Eight weeks, four groups and notable findings

Measurements taken by the researchers

Over eight weeks, the researchers monitored several health indicators in the mice:

• Body weight and total body composition
• The quantity and placement of body fat, including abdominal fat
• Strength and physical performance
• Muscle and heart function
• Blood sugar regulation and insulin response

They placed particular emphasis on the way the animals’ muscles reacted to insulin. More effective insulin signalling in muscle tissue normally enables the body to remove glucose from the bloodstream more efficiently, helping blood sugar stay within a healthier range.

Weight training outperforms running for blood sugar

Each form of exercise produced obvious benefits. In comparison with inactive mice, both the runners and the weightlifting mice had less abdominal and subcutaneous fat, as well as improved blood sugar control.

The surprise came when the researchers compared the two active groups: resistance training matched or outperformed running on key markers of glucose regulation.

The team reported that the mice using the strength-training arrangement had particularly substantial improvements in insulin signalling within skeletal muscle. This shift seemed to lead to more efficient blood sugar regulation, indicating that resistance exercise could have antidiabetic effects at least as powerful as - and potentially stronger than - endurance exercise alone.

Published on 30 October 2025 in the Journal of Sport and Health Science, the findings add to the growing case for placing strength training alongside cardio, rather than below it, in diabetes-prevention guidance.

What this may mean for type 2 diabetes

This was a mouse study rather than a human one, so its outcomes cannot be directly applied to people. Nevertheless, the changes observed in the animals’ muscle cells appear strongly relevant to human disease.

According to International Diabetes Federation estimates, type 2 diabetes affects approximately one in nine adults globally. People at risk are often advised to “be more active”, but that guidance is frequently imprecise.

By showing how resistance training changes insulin-related pathways in muscle, the study hints at new drug targets and clearer exercise prescriptions.

If researchers can identify the precise molecular changes produced in trained muscle, drug developers may be able to create medicines that reproduce some of these effects. Meanwhile, healthcare professionals may have greater confidence in advising strength work as a key element of prevention and management, rather than merely an additional activity.

Cardio vs weights: is there really a need to choose?

For anyone considering what this means in everyday practice, the study does not suggest that running has no value. On the contrary, endurance-trained mice also reduced fat and improved blood sugar control. Cardio exercise additionally benefits heart function, lung capacity and mental health.

Instead, the research indicates that weight training offers a distinct advantage, especially through its ability to reshape muscle tissue and improve insulin sensitivity.

In day-to-day life, combining the two forms of activity often delivers the strongest outcomes. Brief runs or brisk walks can support heart health, while two or three weekly strength sessions can aid muscle development and metabolic control.

What “strength training” can involve for everyday people

Strength training need not involve a daunting gym environment or very heavy barbells. Its central idea is straightforward: muscles must work against resistance in order to adapt.

That resistance may come from:

• Your own body weight, such as squats, push-ups, lunges and planks
• Resistance bands used at home
• Dumbbells or kettlebells in a gym or living room
• Machines that support the movement for beginners

For a person worried about blood sugar, an initial routine could consist of full-body strength training on two non-consecutive days each week. Depending on their fitness level, each workout might include 6–8 exercises for the major muscle groups, completing one to three sets of 8–12 repetitions.

As a person gets stronger, the resistance can be raised progressively - just as the mice had to push increasingly heavy lids to access their food.

Key terms for understanding the science

A number of scientific concepts are central to this research. Knowing what they mean makes the mouse findings more meaningful in daily life.

• Insulin sensitivity: the degree to which the body’s cells respond effectively to insulin. Greater sensitivity means cells require less insulin to take in the same quantity of glucose.
• Insulin resistance: a condition in which cells do not respond to insulin’s signal. The pancreas must produce more insulin to manage blood sugar, and this ongoing demand can contribute to type 2 diabetes over time.
• Skeletal muscle: the muscles connected to bones that make movement possible. They serve as an important glucose “sink”, drawing glucose from the blood both during activity and as they adapt to exercise.

By altering the way skeletal muscle responds to insulin and processes glucose, strength training effectively improves one of the body’s principal mechanisms for handling rises and falls in blood sugar.

Where the research could go next

This mouse model creates opportunities for additional research. Scientists can now alter diet, training volume or individual genes to determine which combinations produce the greatest improvements in blood sugar control. They may also assess potential medicines alongside exercise to establish whether their effects are cumulative or overlapping.

For people with prediabetes or a strong family history of type 2 diabetes, this evidence reinforces a straightforward practical point: gaining and retaining muscle is not solely about looks or physical strength. It may become a fundamental part of safeguarding long-term metabolic health, one workout at a time.