Strength Training May Match Cardio for Type 2 Diabetes Blood Sugar Control

For many years, jogging and cycling have been promoted as the benchmark activities for reducing the risk of type 2 diabetes. However, fresh research indicates that strength training may be just as effective as traditional cardio - and may occasionally be superior - for managing blood sugar and improving the body’s use of insulin.

Why blood sugar control matters so much

Glucose is a simple sugar that provides energy for almost every cell in the body. Blood glucose rises after eating, and the hormone insulin helps transfer this glucose from the bloodstream into muscle, fat and liver cells, where it is either used or stored.

In a healthy fasting state, blood sugar generally ranges from around 0.70 to 1.10 grams per litre of blood. Problems arise when these levels remain elevated for prolonged periods. This condition, known as hyperglycaemia, commonly signals an insulin problem: the body may not produce enough insulin, or cells may no longer respond to it effectively.

Over time, this disruption can result in type 2 diabetes. According to 2024 International Diabetes Federation data, the condition now affects approximately one in nine adults globally. High blood sugar can damage nerves and blood vessels, raising the likelihood of heart disease, kidney failure, loss of vision and other complications.

Regular physical activity is one of the most effective non-drug ways to lower blood sugar and improve insulin sensitivity.

Cardiovascular exercise has traditionally dominated advice on diabetes. But running, particularly at more demanding intensities, can be difficult to maintain, uncomfortable for the joints or simply unattractive to many people. Finding alternatives that are equally effective is therefore more than an academic exercise.

Inside the mouse “gym”: how scientists made rodents lift weights

Scientists at Virginia Tech and the University of Virginia set out to compare resistance training directly with endurance exercise. Published on 30 October 2025 in the Journal of Sport and Health Science, their research involved mice but was designed to reflect human-style exercise as closely as possible.

A clever setup for rodent strength training

Making mice lift weights involves more than giving them a miniature barbell. The researchers instead developed a new weightlifting model for mice. The animals were housed in cages where they needed to push up a weighted lid to reach their food. Every push engaged the forelimb and upper-body muscles in a manner comparable to resistance exercise in people.

The weight attached to the lid was increased gradually over time. This escalating resistance reproduced the progressive nature of a strength programme, much like adding plates to a barbell at the gym.

The team built what is essentially the first “mouse weight room”, allowing systematic strength training over several weeks.

The endurance group and the couch-potato controls

Strength work was not the study’s only focus. To compare forms of training, the researchers created several groups:

• A resistance group: mice that raised a weighted cage lid to access food.
• An endurance group: mice given unrestricted access to a running wheel.
• Two sedentary groups: inactive mice fed either a standard diet or a high-fat diet.

Every group was monitored closely. The researchers wanted to establish how each form of activity influenced body weight, fat distribution, muscle performance, heart function and, most importantly, blood sugar and insulin sensitivity.

Eight weeks of training, and a surprising winner

Over eight weeks, the researchers monitored the mice as closely as athletes at a training camp. They assessed changes in body composition, measured physical performance and performed detailed tests on blood and muscle tissue.

Cardio and weights both helped, but not equally

Compared with inactivity, endurance running and resistance training both delivered clear health improvements. Active mice had less subcutaneous and abdominal fat than sedentary animals. They also processed glucose more efficiently, while insulin signalling in skeletal muscle improved.

When the researchers lined up the results, strength training came out at least as good as running, and often better, for blood sugar regulation.

Lead author Chen Yan, an exercise medicine specialist at Virginia Tech, said the results showed that both exercise types reduced damaging fat deposits and improved the response of muscles to insulin. However, the mice trained with resistance showed especially marked antidiabetic effects, indicating that muscle-focused exercise could be a potent approach to blood sugar control.

What was happening inside the muscles

The researchers investigated signalling pathways within skeletal muscle, the muscle tissue that moves the limbs and reacts directly to training. They examined how insulin’s signal travels through cells, activating glucose transporters that draw sugar from the bloodstream into muscle fibres.

These pathways became more active and responsive in both the running and strength-training groups. Some molecular changes were particularly notable in the resistance group, suggesting distinct advantages from challenging muscles against a load rather than repeatedly moving them over extended periods.

What this could mean for type 2 diabetes

Type 2 diabetes commonly develops slowly. Initially, the pancreas releases extra insulin to compensate for resistance in the body’s tissues. As the condition advances, this system becomes exhausted and blood sugar increases. Many medicines are intended to improve insulin sensitivity or enable the body to use glucose more effectively.

The changes seen in trained mouse muscles point towards potential new treatment targets beyond standard medication.

By altering specific skeletal-muscle signalling pathways, resistance training may do more than reduce blood sugar temporarily. It could change the way muscle tissue manages glucose over the longer term, potentially easing pressure on the pancreas.

The researchers propose that a better grasp of these pathways could contribute directly to new treatments. Such options could include medicines that replicate the molecular effects of strength training, or individualised programmes combining medication with tailored resistance exercise.

Can this apply to humans who just hate running?

The central question is whether people should regard the squat rack as seriously as the treadmill when seeking to prevent or manage diabetes. Mice are not people, and all animal models have limitations. Nevertheless, their muscles respond to exercise in many of the same ways as human muscles, explaining their extensive use in metabolic research.

Public health recommendations already advise adults to undertake both cardio and strength training. Diabetes guidance frequently emphasises brisk walking, cycling and swimming, but often treats resistance exercise as an additional extra. This study adds support to the view that building and using muscle under load should play a key part in strategies for blood sugar control.

For those who cannot or will not run, resistance exercise may offer a different, and possibly more practical, route to healthier blood sugar.

How a realistic strength routine might look

For adults without medical contraindications, an effective basic strength programme does not require expensive equipment. The aim is to regularly challenge the main muscle groups, allowing them to adapt and become more responsive to insulin.

Practical examples of resistance exercises

• Bodyweight exercises, including squats, wall sits, press-ups and lunges.
• Resistance-band exercises suitable for home or the workplace.
• Free weights, kettlebells or gym machines.
• Everyday loaded activities, such as carrying shopping bags or repeatedly climbing stairs.

Even brief sessions two or three times weekly can alter how muscles process glucose. Progression is essential: gradually increase the weight, number of repetitions or level of difficulty, just as the weight of the lid rose in the mouse cages.

Benefits, risks and smart combinations

The advantages of strength training extend beyond glucose management. It increases muscle mass, promotes bone health, enhances balance and helps preserve independence in later life. By making daily movement easier and encouraging a generally more active lifestyle, these benefits can also indirectly aid diabetes management.

Poor technique or excessively heavy loads can create risks. Strained joints, back pain and muscle injuries may occur. Anyone with heart disease, advanced diabetes complications or another chronic condition should consult a health professional before beginning an intensive strength-training programme.

Many experts now favour a blended approach: combine moderate cardio with regular resistance work for broader metabolic protection.

For example, a weekly plan could involve brisk walks on most days alongside two short strength sessions using dumbbells or bands. This combination draws on cardio’s heart and lung benefits while also gaining the blood sugar and muscle benefits of resistance work.

A few terms worth unpacking

Two scientific terms are particularly relevant to this study: insulin sensitivity and skeletal muscle signalling.

Insulin sensitivity refers to how powerfully the body’s cells react to a particular amount of insulin. When sensitivity is high, cells require only a small amount of insulin to take up glucose. With low sensitivity, also called insulin resistance, the body has to release more insulin to produce the same result, placing increasing stress on the pancreas over time.

Skeletal muscle signalling describes the sequence of molecular events that begins when insulin binds to its receptor on the surface of a muscle cell. The chain carries a message into the cell, directing transport proteins to move to the cell membrane and bring in glucose. Exercise modifies numerous stages of this process, helping it work more effectively.

The Virginia mouse study suggests that placing muscles under load through resistance exercise may adjust these signals in a particularly beneficial manner. More research in humans is still required, especially among people already living with diabetes, but the findings provide firmer scientific support for a straightforward idea: lifting something heavy a few times each week may be a powerful ally against high blood sugar.