Exercise and type 2 diabetes: how much, what kind, and how to start safely

Why muscle matters in type 2 diabetes

Type 2 diabetes is the form in which the body no longer uses insulin effectively. The World Health Organization counts 830 million people living with diabetes in 2022, against 200 million in 1990, and lists regular physical activity, alongside diet, weight and not smoking, among the ways to prevent or delay type 2 diabetes. It also names physical activity as part of treatment, together with diet, medication and screening for complications.

Working muscles take up glucose from the blood. This is why exercise is not an extra in diabetes care but one of its tools, and why both endurance work and strength training appear in every serious guideline.

The weekly targets from the ADA

The American Diabetes Association's position statement on physical activity sets out the following for most adults with diabetes:

• Aerobic activity: 150 minutes or more a week at moderate to vigorous intensity, spread over at least 3 days, with no more than 2 consecutive days without activity. Shorter durations, at least 75 minutes of vigorous or interval training, may be enough for younger and fitter people.
• Resistance training: 2 to 3 sessions a week, on non-consecutive days.
• Flexibility and balance: 2 to 3 times a week for older adults with diabetes; yoga and tai chi can be included.
• Less sitting: interrupt prolonged sitting with light activity every 30 minutes.

These are the same broad figures that WHO gives to all adults, including those with chronic conditions, which makes them easy to remember. The calculator on this page compares your usual week with them. For the general logic of weekly minutes, see how much exercise per week.

What the trials show

In the JAMA meta-analysis by Umpierre and colleagues, which pooled 47 trials and 8,538 patients, structured exercise training was associated with an average fall in HbA1c of 0.67 percentage points compared with control groups. Aerobic training, resistance training and the combination were each associated with improvement. Programmes of more than 150 minutes a week were associated with a reduction of 0.89 points, against 0.36 points for 150 minutes or less.

The same analysis carries a useful warning: advice to be more active, given alone, was not associated with a change in HbA1c. Advice combined with dietary advice was. In other words, a leaflet is not a programme. What helps is a plan that is actually carried out.

For people who do not yet have diabetes but are at high risk, the Diabetes Prevention Program is the reference trial. Among 3,234 adults with raised blood glucose, a lifestyle programme aiming for at least 7% weight loss and 150 minutes of activity a week reduced the incidence of diabetes by 58% compared with placebo over an average of 2.8 years, more than the drug metformin did.

Breaking up sitting

A small randomised crossover trial by Dunstan and colleagues, published in Diabetes Care in 2012, studied 19 overweight adults aged 45 to 65. Interrupting sitting with 2 minutes of walking every 20 minutes lowered the rise in glucose and insulin after a test drink, compared with sitting without a break. The effect was seen with light walking as well as moderate walking.

For a desk job, this means that the walk to a colleague, a call taken standing and a short loop after lunch all count. The ADA adds that these breaks complement structured exercise; they do not replace it. Our guide on sitting all day gives practical ways to build them into a working day, and walking meetings turn some of them into work time.

Safety points to agree with your doctor

If you have diabetes, talk to your doctor or diabetes team before starting a new exercise programme, especially if you take insulin or tablets that stimulate insulin release, or if you have eye, foot, kidney or heart complications. Stop and seek advice in case of chest pain, unusual breathlessness, dizziness or symptoms of low blood sugar.

The ADA position statement highlights several points:

• Low blood sugar. Exercise-induced hypoglycaemia is common in type 1 diabetes and occurs, to a lesser extent, in type 2 diabetes treated with insulin or insulin secretagogues. Your doctor may adjust doses on exercise days. Metformin is described as generally safe without adjustment.
• Feet. With peripheral neuropathy, proper foot care and appropriate footwear help prevent ulcers.
• Eyes. In severe non-proliferative or unstable proliferative retinopathy, vigorous aerobic or resistance exercise, jumping, head-down positions and breath holding should be avoided.
• Progression. Start below your capacity and increase gradually.

A first month that holds

Here is an illustrative plan, to be adapted with your care team, for someone currently doing little:

1. Weeks 1 and 2: three brisk walks of 20 minutes, on Monday, Wednesday and Saturday, and a two-minute walk every half hour at work.
2. Weeks 3 and 4: walks of 30 minutes, plus two short strength sessions on non-consecutive days, with squats to a chair, wall push-ups and rows with a band.
3. From month two: five days of 30 minutes in total, two or three strength sessions, never two days in a row without moving.

Strength work need not involve a gym. The ten essential movements cover the main muscle groups with simple equipment. What matters most is regularity: the ADA's rule of no more than two days without activity is, at heart, a consistency rule.

Keep the rhythm with Never Skip Club

Never Skip Club is a free app built for exactly this kind of regularity. You choose a body area, a level (Easy, Moderate or Intense), a duration of 20, 30 or 45 minutes and a place, and the app builds a guided session of five or six animated exercises in a minute. In a crew of three to seven friends, you set a rhythm, for example four sessions a week, and the ranking rewards the share of planned sessions you actually complete, not extra volume. That suits a condition where steady weeks count more than heroic ones.

Create your free account, start with an Easy session, and invite two friends to hold the rhythm with you. If you would like an expert to check your technique and adapt the sessions, you can also book a coach from our network: tell the coach about your diabetes and your doctor's advice at the first session.