Exercise And Blood Sugar: What You Need To Know
Get moving to better manage your blood glucose levels.
July 30, 2021
We don’t have to tell you that exercise has a host of health benefits. From helping to control weight, lower blood pressure, strengthen muscles and improve your mood and sleep health, physical activity gets a gold star and should be part of any healthy lifestyle. But did you know that there's a connection between exercise and blood sugar levels?
Diabetes and exercise: How working out reduces your risk
Exercise not only makes you look and feel fit, it also has a host of positive health impacts. One that’s less known than others: exercise has been shown to lower blood sugar levels and helps your body be more sensitive to insulin (so sugar is moved out of the blood efficiently)— reducing your risk of developing insulin resistance and diabetes. For those who don’t have diabetes (but could be on the cusp of developing “prediabetes”), exercise is an important lifestyle habit that may reduce your risk of developing diabetes (when coupled with a healthy diet).
And the best part: Exercise doesn’t have to be an intense kickboxing class or running on the treadmill (unless that’s your thing). Walking and even activities like gardening count as exercise, too. The key is to get moving so your entire body can benefit.
Exercise and type 2 diabetes: 50% reduction in risk
What the science says: Clinical studies suggest that consistent exercise can reduce the risk of type 2 diabetes by up to a staggering 50%.
For those with prediabetes or diabetes, the evidence is just as strong: Consistent physical activity has been shown to improve insulin sensitivity and glycemic control, while reducing the risk of mortality, according to a consensus paper published by the American Diabetes Association. Exercise is also a natural stress buster—important because chronic stress can make it harder to keep blood sugar levels in check.
Evidence-backed exercise tips
Lace up those sneakers (or put on those swim goggles) with these strategies in mind:
Mix up your workouts. If you’re wondering if cardio or weights are better at helping manage blood glucose, the answer is: both. Research has shown that aerobic workouts and strength training are both effective at improving glycemic control, on par with antidiabetic meds in some cases. The key is to find exercises and activities you’ll stick with; consistency is what matters most.
Go high-intensity. If you’re able to work out a little harder, go for it. One report found that when subjects who didn’t have diabetes engaged in two weeks of sprint interval training (which required only a max of 20 minutes of exercise per week), they showed increased insulin sensitivity for up to three days after. Among those with diabetes, the results were even more striking: Subjects who did quick high-intensity exercise sessions reduced their average blood glucose by 13% up to 72 hours after exercise.
Time your workouts. Using a continuous glucose monitor (CGM) — whether you have diabetes or not — can help you get a sense of how your blood sugar levels rise and fall before, during, and after a workout. It’s a good way to measure glucose control. And this can be particularly important if you have diabetes. Research shows that glucose levels will reach their peak within 90 minutes of your last meal. That means you’ll probably want to time your workouts to begin within 30 minutes of eating. This way, when your glucose levels naturally dip during exercise, you can reduce the risk of them dropping too low (which we’ll cover next). But remember: 30 minutes post-meal isn’t an exact science. Talk to your doctor and track your levels with a CGM to see how your body responds to different workouts and different meals. Use that data to help you find the safest time to be active.
Follow the 15-15 rule. Hypoglycemia (abnormally low blood sugar) can result during exercise if you don’t time your meals accordingly. If your blood sugar dips below 100 mg/dL after a workout, the American Diabetes Association recommends having 15-20 grams of carbs (a tablespoon of sugar), then check it again in 15 minutes. If it’s still below 100 mg/dL, keep repeating the 15 grams/15 minute cycle until you cross that threshold.
Get moving! No matter what type of exercise you do, find something that gets your heart rate pumping and that you enjoy. And make it part of your weekly routine. Ideally aim for 150 minutes per week of moderate intensity exercise (the recommended fitness guideline), but talk to your doctor about what makes the most sense for you based on where you are in your journey. Exercise and blood sugar levels are intrinsically linked, not to mention a whole host of other health benefits you'll get to enjoy.