- Research has shown that initiating exercise 30 min after meals improves blood glucose control.
- Performing aerobic exercise, like walking, before resistance exercise is ideal.
- While 45 minutes of exercise is ideal, benefits can be seen with as little as 10 minutes.
If you’re watching your blood sugar due to having diabetes or prediabetes, you’re probably aware that physical activity is recommended to help manage it. You may even be cognizant of the recommendation regarding physical activity for those with type 2 diabetes—which is to include 45 minutes of any exercise type at any intensity following meals to help improve post-meal blood glucose response.
We’ve previously reported on studies that say that walking for just two minutes after meals helps lower blood sugar and that being physically active in the afternoon or evening can help control blood sugar better than morning exercise.
Some of the information may seem conflicting—and confusing. To try to fine-tune the exercise prescription for blood sugar control, researchers at the University of Rome decided to dig into the available research to see if they could develop more refined recommendations.
Start Moving 30 Minutes After a Meal
When considering any situation involving exercise, researchers typically consider the FITT Principle, which stands for frequency, intensity, time (duration) and type of exercise. These are the parameters these researchers used for this review. In this case, they also added a third “T” for timing—looking at the best time relative to eating to be physically active for better blood sugar control.
Researchers took into consideration the timing of when glucose levels tend to peak after eating. In people without diabetes, glucose typically peaks 30 to 60 minutes after eating. For those with diabetes, peak glucose levels are reached between 60 and 120 minutes following a meal.
After combing through numerous studies, these researchers suggest initiating exercise before blood glucose levels hit their peak. This means that those without diabetes should start moving 15 minutes after eating and those with diabetes should start moving 30 minutes after eating to better manage blood sugar levels.
Aerobic Before Resistance
Researchers then reflected on what types of exercise are best for blood glucose levels. Ultimately, aerobic exercise—like walking, jogging, stair-climbing, elliptical and rowing—and resistance exercise, each on its own, will help manage blood sugar. These researchers add, though, that the combination of the two appears to be your best bet, stating that research demonstrates that a combination of both types of exercise offers superior benefits compared to each type on its own for improving 24-hour glucose control.
Fine-tuning this recommendation even further, they say that the evidence suggests that starting your exercise session with aerobic exercise followed by resistance training may have even greater benefits than doing it in reverse.
Even a Small Amount of Exercise Counts
Regarding the intensity and duration of your exercise sessions, the researchers note that current guidelines for those with type 2 diabetes recommend engaging in 45 minutes of exercise at any intensity to improve post-meal glucose management. They also acknowledge that this is not practical for everyone.
The ideal length of the post-meal exercise session falls within a wide range of times and offers some wiggle room, which is great for those who don’t have the time or capacity to head out for a 45-minute walk after each meal. Researchers note that exercising from 10 to 120 minutes at moderate intensity has been shown to be effective in helping to regulate post-meal blood sugar levels. A moderate intensity is where you feel slightly out of breath but can still carry on a conversation.
This review also suggests that taking activity breaks throughout the day adds significant value in managing blood sugar, especially when combined with an exercise routine. Based on the evidence, the researchers recommend taking a three-minute activity break for every 30 minutes of sitting, in addition to performing a 20- to 30-minute continuous exercise session.
Mobility Considerations
Often left out of physical activity recommendations is how people who have limited exercise capabilities can benefit from some type of movement. These researchers considered this as well.
For those who cannot exercise, the researchers found evidence that even small movements can help manage blood glucose levels after eating. This can include leg fidgeting or contracting and squeezing the muscles in the legs. If unable to use the lower body, upper body movements will help, too (think boxing movements or moving your arms above your head).
Our Expert Take
Ultimately, this review suggests that all movement counts toward helping to manage blood sugar levels—whether you have diabetes or not. Where these researchers really homed in and refined the recommendations is with the timing of the exercise for optimal post-meal control.
For those without diabetes, aim to start moving 15 minutes after eating, and for those with diabetes, try to start moving 30 minutes after eating. The combination of aerobic exercise plus resistance exercise—and beginning your exercise session with aerobic activity—along with frequent activity breaks throughout the day seems to be the best combination for blood sugar control.
