When it comes to managing type 2 diabetes, exercise is one of the most potent treatments out there, according to a position statement from the American Diabetes Association (ADA). Moving more helps with blood sugar control, insulin sensitivity and weight maintenance — all important things to keep diabetes in check.
But there are certain precautions all people with diabetes — whether they're in great shape or new to exercise — need to take. Here's a look at what you need to do to sweat safely and reap the best results.
1. Aim for Aerobic Activity Almost Every Day
How It Helps
When you do aerobic exercise, whether it's more moderate activity like walking or more vigorous, like running or a cycling class, your muscles use glucose, the sugar in your bloodstream, to fuel your workout.
"This brings down your blood glucose levels, and it can last for hours after finishing a cardio activity," says Julia Iafrate, DO, assistant professor of rehabilitation and regenerative medicine at Columbia University Medical Center in New York City. It also helps your body better use insulin, per the ADA.
You don't have to run a marathon to see results, either. One study published July 2016 in Diabetologia found that when people with prediabetes (a precursor to type 2) did moderate-intensity exercise like walking briskly for 11.5 miles each week, they improved glucose tolerance by 7 percent.
How to Do It
The ADA recommends all adults with type 2 diabetes engage in at least 150 minutes of moderate- to vigorous-intensity activities like walking, running, swimming or cycling each week.
"You should spread it over at least three days a week, with no more than 48 hours without activity, since exercise's effects on insulin sensitivity only last for a day or two," says Sheri Colberg-Ochs, PhD, an exercise physiologist and professor emerita of exercise science at Old Dominion University.
If you haven’t been active and have diabetes-related complications such as high blood pressure, neuropathy or retinopathy, talk to your doctor before you start any sort of workout program.
Total beginner? Consider working with an exercise physiologist to come up with a program that's right for you (this is often covered by your insurance), Dr. Iafrate says. It's fine to start slow, with just five to 10 minutes of moderate activity until you can slowly build up to 30 minutes most days of the week.
If you're no stranger to the gym, bring your workout up a notch by throwing in some interval training, says Jacqueline Shahar, MEd, a clinical exercise physiologist and diabetes care and education specialist at the Joslin Diabetes Center in Boston. This means intervals of high-intensity effort alternated with periods of recovery.
When researchers had people with type 2 diabetes do four to six 30-second cycling sprints followed by four-minute recoveries, they had better glucose metabolism in their muscles than those who just biked at a moderate intensity for 40 to 60 minutes, according to a study published March 2017 in the Scandinavian Journal of Medicine & Science in Sports.
If you're a novice to intervals, it can be as simple as throwing some hills into your walk or run, or picking up the pace for 30 to 60 seconds followed by four minutes at a more moderate speed.
Workouts to Try
Regardless of your activity, make sure you stretch for five minutes after your workout.
"It's important for everyone, but especially people with diabetes, since the extra glucose in the bloodstream can end up sticky like sugar on joint surfaces, actually changing its structure over time," Colberg-Ochs says.
As a result, joints and muscles become more brittle and less flexible, making you more likely to get overuse injuries.
2. Add Strength Training to the Mix
How It Helps
Even if you do cardio most days of the week, there's another crucial component your exercise regimen should include: resistance training. This is true for everyone, but especially those with diabetes.
"People with diabetes are at risk for lower muscle strength," Colberg-Ochs says.
One March 2016 study published in Diabetes Care, for example, found that people with type 2 diabetes had an increased amount of fat in their leg muscles, leading to muscle weakness.
Resistance training builds muscle mass, which in turn enhances insulin sensitivity.
"There are two places your body stores carbohydrates — your muscles and your liver," Colberg-Ochs explains. If you don't have much muscle mass, those carbs end up spilling out into your bloodstream, raising blood glucose levels, or being stored by your body as fat.
"Most of the time, the fat ends up in your central abdomen, which makes you even more insulin-resistant," Colberg-Ochs adds. But if you do have muscle mass, these carbs can go into your muscles and then get used up through either aerobic or resistance-training exercises.
There are also a host of other benefits to strength training:
- Weight loss: "When you build muscle mass, you raise your metabolism, which can help you manage your weight," Shahar says.
- Better balance: Building strength also improves balance, which can be weaker in people with diabetes, particularly those who suffer from related conditions like neuropathy, or numbness in their legs or feet. Indeed, older adults with type 2 diabetes who did resistance training for six weeks were significantly less likely to fall than those who didn't, according to an April 2010 study published in Diabetes Care by Colberg-Ochs and colleagues.
- Stronger bones: This is important because people with type 2 diabetes are at higher risk for fractures, says Colberg-Ochs.
- Mood boost: Resistance training is associated with a significant reduction in depressive symptoms, according to a review of 33 studies published June 2018 in JAMA Psychiatry. This is important for people with diabetes, who are more likely to experience depression, according to the Mayo Clinic.
How to Do It
The ADA recommends aiming for two to three strength-training sessions a week.
If you're a novice, consider working with an exercise physiologist or a trainer to come up with a plan that's right for you. "It's a good idea, at least at the beginning, to make sure you don't start out too aggressively, and that you're doing exercises correctly," explains Shahar.
When you're just beginning, it's best to just use your own body weight as resistance, with moves such as planks, lunges and modified push-ups, advises Colberg-Ochs. But if you can do eight to 12 reps without the muscle feeling fatigued, it's time to move it up a notch.
"You should be doing each exercise to the point where it's hard to do the last repetition without helps," Colberg-Ochs says.
You can do this by using resistance bands, hand weights (like dumbbells), weight machines at the gym or even simple household items like full water bottles or soup cans.
"The heavier the weight, the more glycogen you use, which enhances your body's insulin action," explains Colberg-Ochs. It's also better at building up muscle fibers, which in turn helps improve insulin sensitivity.
Workouts to Try
3. Don’t Forget a Dose of Mindfulness
How It Helps
Mindfulness-based exercises such as yoga and tai chi have been shown to help people with type 2 diabetes.
A September 2018 review published in Endocrinology and Metabolism concluded that yoga can be an effective tool when it comes to blood glucose control, and it also can help treat other, related conditions such as high blood pressure.
There are a couple reasons why these types of workouts may be helpful: Besides promoting physical activity, they also help reduce stress, which has been shown to worsen type 2 diabetes, Dr. Iafrate says. They also emphasize flexibility, strength, and balance at the same time, all three of which are recommended types of training for anyone with diabetes, adds Colberg-Ochs.
How to Do It
While there are no official guidelines on mindfulness-based activities, the ADA recommends flexibility and balance training — which includes yoga and tai chi — two to three times a week. It doesn't matter which type of yoga, either, since there's no specific research showing one is more effective than another, says Colberg-Ochs.
Workouts to Try
How to Stay Safe When Exercising With Diabetes
Before your workout: You should have a small snack about an hour before your workout, Dr. Iafrate says. Then test your blood sugar about 15 minutes before exercising — it should ideally be between 110 and 150 mg/dL.
During your workout: Check your blood sugar every 30 minutes. Follow what the ADA dubs the 15-15 rule: If your reading is under 100 mg/dL, have 15 to 20 grams of carbohydrate to raise your blood sugar (the equivalent of four glucose tablets, 4 ounces of juice or a tablespoon of honey).
Check your blood sugar again after 15 minutes. If it's still low, you'll have to have another 15 grams of carbohydrates. Repeat this every 15 minutes until your blood sugar is at least 100 mg/dL.
After your workout: If you're doing resistance training, keep in mind that your blood sugar may rise right after your workout. This is because strength training can raise stress hormones such as adrenaline for a short period of time, which tends to drive blood glucose levels up, explains Shahar. If yours is elevated, wait about 30 minutes, then check again before administering insulin or other medications.
- Diabetologia: “Effects of exercise training alone vs a combined exercise and nutritional lifestyle intervention on glucose homeostasis in prediabetic individuals: a randomized controlled trial.”
- American Diabetes Association: Diabetes Care: “Physical Activity/Exercise and Diabetes: A Position Statement of the American Diabetes Association”
- Scandinavian Journal of Medicine & Science in Sports: “Increased insulin‐stimulated glucose uptake in both leg and arm muscles after sprint interval and moderate‐intensity training in subjects with type 2 diabetes or prediabetes.”
- Diabetes Care: “Reduced Lower-Limb Muscle Strength and Volume in Patients With Type 2 Diabetes in Relation to Neuropathy, Intramuscular Fat, and Vitamin D Levels.”
- Diabetes Care: “Balance Training Reduces Falls Risk in Older Individuals With Type 2 Diabetes.”
- JAMA Psychiatry: “Association of Efficacy of Resistance Exercise Training with Depressive Symptoms: Meta-analysis and Meta-regression Analysis of Randomized Clinical Trials.”
- Endocrinology & Metabolism: “Therapeutic Role of Yoga in Type 2 Diabetes.”
- Journal of Diabetes Research: “The Effects of Tai Chi on Type 2 Diabetes Mellitus: A Meta-Analysis.”
- Diabetes Care: “Standards of Medical Care in Diabetes—2019.”
- Mayo Clinic: "Diabetes and Depression: Coping With the Two Conditions"