What Happens to Your Blood Sugar When You Exercise?

Exercise plays an important part in maintaining your health. There are countless benefits and effects to physical activity, and these impacts are especially important to people living with type 1 and type 2 diabetes. How does exercise affect your blood sugar? Does exercise impact insulin levels? Can people with diabetes work out without suffering from low blood sugar? Here’s what you need to know about exercising safely with diabetes.

Diabetes and Exercise

Exercise is essential for people living with diabetes, as well as those hoping to prevent diabetes. Exercise can help lower blood sugar levels and A1C. Anyone with diabetes should do their best to follow the CDC’s exercise guidelines, getting 20-30 minutes of exercise each weekday. Additionally, it’s best to do exercises to work all muscle groups at least two days a week.

Why is exercise so important for people with diabetes? Exercise increases your body’s sensitivity to insulin. As you exercise, your body uses up the energy stored in your cells. Once those stores are empty, it will turn to glucose and insulin to keep going. This can help temporarily lower your insulin levels (the effects can last up to 24 hours), helping you keep your diabetes under control.

Exercise is also critical for pre-diabetic individuals, as it can help them lower their A1C and avoid developing the condition altogether. In a study from the National Institutes of Health, researchers discovered that moderate-intensity exercise increased insulin sensitivity by 51% — while high-intensity exercise increased it by 85%. The data makes it clear that exercise is not optional for individuals with diabetes and that physical activity is critical.

Exercising Safely with Diabetes

While exercise is an important part of a person’s diabetes management plan, it is possible to overdo your time on the treadmill. People with diabetes are at an increased risk for hypoglycemia (low blood sugar), particularly if they are taking insulin through injection or insulin secretagogues. These individuals must make sure that they are exercising safely, taking their blood sugars into consideration with each workout.

How can you exercise safely? Here are a few tips:

Check Your Blood Sugar Before Your Workout

People with diabetes must monitor their blood sugars throughout the day, and before a workout is no exception. The reason for this is twofold: firstly, checking your sugar levels ensures you aren’t low before you start your workout. This will keep you safe and allow you to give your all during your run, walk, yoga class, or any other form of exercise.

Secondly, checking your sugar levels before your workout gives you a baseline by which you can measure the benefits of exercise. Looking at the change in your levels before and after a workout can be a great incentive to continue hitting the gym.

Bring Snacks to Keep Your Sugars Up

What do you do if your blood sugars are low before your workout? It’s time to get some fast-acting carbohydrates into your system.

The American Diabetes Association suggests having 15-20 grams of carbohydrates if your blood sugar reads 100 mg/dL or less before a workout. This can include:

  • Four glucose tablets
  • Four ounces of fruit juice or soda (not diet)
  • One tablespoon of sugar or honey

Once you’ve had some carbs, wait 15 minutes and check your sugar levels again. Repeat this process until your reading is at least 100 mg/dL, and then you can start (or resume) your exercise for the day.

Know When To Stop

Another important element of exercise is knowing when your body’s had enough. Overexerting yourself can lead to injury — and for someone with diabetes, it can have severe health consequences.

Take it slow and watch for any signs of low blood sugar. These can include feeling shaky, weak, or confused. If this occurs, stop exercising right away! Rest, check your levels, and take in some carbohydrates to get your levels back up to normal.

Over time and with repeated exercise sessions, you will become more familiar with your body and know when you can push yourself a little harder. But when you begin a new exercise routine, you must take it slow and carefully monitor your sugar levels — otherwise, the health risks might outweigh the benefits.

Whether you’re prediabetic or living with type one or type two diabetes, exercise is a critical part of managing your condition. However, it is important to do so safely. Make sure you take the time to understand how exercise affects your blood sugar personally.

Aaron Smith on Diabetesknow.com

Aaron Smith is an LA-based content strategist and consultant in support of STEM firms and medical practices. He covers industry developments and helps companies connect with clients. In his free time, Aaron enjoys swimming, swing dancing, and sci-fi novels.

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