Medically reviewed by Lindsey DeSoto, RD

• Research suggests that evening or afternoon exercise may be most effective at lowering blood sugar.
• Experts believe cortisol levels and meal timing could explain why people see greater blood sugar decreases from late-in-the-day workouts.
• Any physical activity is good for type 2 diabetes management, and it’s important that people with this condition try to exercise for 150 minutes per week.

Along with diet changes and medications, regular exercise helps manage blood sugar if you have diabetes. While movement at any time of day can help, some research suggests that working out later in the day may have the greatest impact.

Why Evening Exercise May Be Best for Blood Sugar

Getting in a workout at any time is good for your health. But the best time to exercise for blood sugar management seems to be later in the day.

In a recent review of studies, experts concluded that afternoon or evening exercise may lead to greater blood sugar control in people with type 2 diabetes. Late-in-the-day exercise was also associated with improvements in insulin sensitivity, or the body's ability to respond to insulin and manage sugar in the bloodstream. Morning exercise did not appear to be as effective.

Similarly, a 2019 study followed men with type 2 diabetes who took part in high-intensity interval training (HIIT) for two weeks. Those who did HIIT in the afternoons had improved blood sugar levels, while morning exercisers saw the opposite effect.

Researchers emphasize that more long-term research is needed. However, there are a couple of theories as to why evening exercise may be better for blood sugar:

• Cortisol: Your cortisol (a stress hormone) naturally spikes in the morning. This triggers the body to release stored sugars, raising blood sugar for people with diabetes. Exercising in the morning can raise cortisol even more, which could explain why it may not be as effective at lowering blood sugar.
• Meal timing: Research shows that workouts done after you eat are better at limiting blood sugar spikes. People who work out first thing in the morning likely aren't doing so after a meal, so they may not reap those benefits.

How Exercise Affects Blood Sugar

Though afternoon or evening exercise may have a more substantial effect on blood sugar, physical activity of any kind can help you manage blood sugar spikes in both the short and long term.

Short-term Effects

During your workout and immediately after, you could experience both positive or negative changes to your blood sugar:

• Pros: As your muscles contract during exercise, they burn sugar directly for energy. Physical activity also improves short-term insulin sensitivity, which means your body is able to better use insulin to move sugar out of the bloodstream. In fact, a workout session can lower your blood sugar for up to 24 hours after.
• Cons: Certain types of exercise—specifically, adrenaline-producing workouts like heavy weightlifting or sprints—can cause short-term blood sugar increases. For example, an older 2013 study found that HIIT workouts increased blood sugar for about an hour after exercise. Still, the exercise had an overall beneficial effect lasting up to 24 hours.

Long-term Effects

Regular exercise is especially helpful for blood sugar management over time. Long-term effects include:

• Better insulin sensitivity: Regular exercise improves how well your cells respond to insulin, which helps manage blood sugar levels.
• Lower hemoglobin A1c (HbA1c) levels: Consistent activity reduces HbA1c, which is a measure of average blood sugar levels over a two to three-month period.
• Greater muscle mass: Muscles take up most of the sugar in your bloodstream after a meal. Because of this, some research suggests that building muscle mass and strength may help lower blood sugar levels over time.
• Possible weight loss: Regular exercise can help you lose weight, which can make it easier to manage your blood sugar levels.

How To Exercise Safely if You Have Diabetes

The American Diabetes Association recommends people with diabetes get 150 minutes of moderate-intensity exercise each week. If possible, that physical activity should be spread out into frequent, shorter sessions with no more than two rest days in a row.

There are lots of different types of workouts you can do to meet your exercise goals, including:

• Aerobic exercise: Walking, jogging, swimming, cycling, and similar cardio workouts are good for blood sugar. As people progress, they can incorporate HIIT or other vigorous-intensity workouts.
• Resistance training: Strength-building exercises help people with diabetes improve insulin resistance, blood sugar levels, lose fat tissue, and more.
• Stretching: More evidence is needed on how yoga, tai-chi, and similar exercises affect blood sugar. However, they can increase flexibility, balance, and quality of life.

Regardless of how you exercise, it's crucial that people with diabetes take steps to ensure that their fitness routine is being done safely. That includes:

• Getting clearance: Before starting a new fitness regimen, talk to your doctor to ensure that your exercise plan is safe for you.
• Checking your blood sugar first: Do a pre-workout check of your blood sugar—if it's below 100 milligrams per deciliter (mg/dL) or above 300 mg/dL, it may not be safe to exercise.
• Monitoring your glucose throughout: After your pre-workout check, continue to monitor your blood sugar levels during and after your workout, since exercise can raise the risk of low blood sugar. Keeping tabs on your blood sugar can also help you find which activities work best for your body.
• Starting small: Take stock of your current fitness level and plan your workouts from there. If you don't work out regularly, start with less intense activities and build up to 150 minutes of weekly exercise.
• Watching for symptoms: Stop exercising if you feel dizzy, shaky, confused, or have a very high heart rate, as these can be signs of low blood sugar. Similarly, take a break if you're having symptoms of high blood sugar, including needing to urinate frequently or feeling very thirsty.

Source link

Kristina Dawson