The best time of day to exercise to keep your blood sugar under control, according to science
Earlier this fall, we learned that walking after eating for only two minutes (yes, really!) can have a significant impact on blood sugar. But beyond sprinkling a little activity “nuggets” as dessert, researchers are still looking to learn more about the best methods, times of day, and intensity levels of exercise that might affect — and potentially help us better manage — blood sugar levels.
While you might think this is only important for people who have or are at higher risk of diabetes, blood sugar is actually important for all people to stay balanced. It is normal for all people that our blood sugar rises and falls during the day. Under normal conditions, our bodies can allow sugar from the blood into our cells, bringing blood levels back into the normal range. When blood sugar levels are high, our pancreas secretes insulin, which alerts our bodies to absorb blood glucose to be used now for energy or later stored in the liver as glycogen for fuel. This process reduces the amount of sugar in the blood. Not to mention, fairly stable blood sugar levels are beneficial for maintaining balanced, sustainable energy levels from morning to night.
For individuals with prediabetes or type 2 diabetes, insulin resistance can change the body’s response to blood sugar; cells stop responding to insulin, and glucose will remain outside the cells. As a result, blood sugar remains high. About 1 in 10 Americans are now diagnosed type 2 and another 38% fit the criteria for prediabetesAccording to estimates from the Centers for Disease Control and Prevention, scientists can’t wait to discover more about the best ways to make the blood sugar roller coaster ride easier and smoother.
A new study published on November 1, 2022 in the journal Diabetology adds fascinating evidence to that aspect of exercise we mentioned earlier. Obviously, the “what” (exercise) makes a difference, as does the “when.” Exercising in the afternoon or evening, ideally between noon and midnight, can significantly reduce insulin resistance and may be better at controlling blood sugar than exercising in the morning.
Read more about this new health study and discover other ways to balance your blood sugar.
What this blood sugar research revealed
The Dutch epidemiology of obesity study is a database of adults between the ages of 45 and 65 with a body mass index of 27 or greater. (Before we continue, please note that Validity and relevance of BMI as an indicator of health is questioned, but since they were determining eligibility for this study, we wanted to mention it.)
For this study, the researchers invited all participants whose body size was representative of their area in the Netherlands to be part of the control group; this resulted in 6700 participants. All of these individuals had a physical examination, which included blood sugar samples that tabulated fasting and postprandial blood glucose and insulin levels. They also filled out questionnaires about lifestyle factors, and some had their liver fat content measured by magnetic resonance imaging.
From this group, researchers randomly selected 955 people to wear an accelerometer and heart rate monitor for four days and nights to track activity levels and overall movement patterns. To categorize exercise time, scientists divided the day into six-hour blocks:
6 am to noon
Noon to 6 p.m
6 pm to midnight
Based on the activity tracker, the researchers sorted each participant into one of those blocks based on when they accumulated the most moderate to vigorous physical activity. At the end of data collection, 755 participants were included in the analysis.
Those who exercised in the afternoon experienced an 18% reduction in insulin resistance, and evening activity was correlated with a 25% reduction in insulin resistance. Activities spread throughout the day or activities performed only in the morning did not appear to affect liver fat content and insulin resistance, while afternoon and evening physical activity did.
In addition to insulin’s effect on blood sugar control, another way glucose can enter cells is through exercise. Muscles need energy when we move and challenge them. In order to fuel us enough to perform the tasks we ask of them, our bodies allow glucose to slip into the muscle cells.
Scientists admit that it is too early in the process of gathering information to explain exactly why afternoon and evening exercise showed better results than morning exercise. They also have yet to prove whether moving exercise time from the morning to the afternoon or evening will improve activity or if there is something else in those with this PM habit that could be moving the needle.
The bottom line
This new study found that afternoon and evening exercise may provide the greatest benefits for blood sugar control. While this is interesting to keep in mind, it is important to note that this is only one study, and a fairly small one at that. Larger, more diverse studies are needed to confirm these findings. Besides, the most important lesson of the story is that activity is beneficial at ANY time of the day. Actually, morning exercise it may actually be your best option if you have a hard time making exercise a part of your daily routine. (Translation: Early risers, keep up the great work if you like a yoga class or a 6am walk!)
Keep in mind that exercise is just one of many healthy ways to lower blood sugar. Sleep, hormones, medication and more hidden factors can affect blood sugar also. What’s on our plate has the biggest impact, of course, so we recommend sprinkling them 29 recipes to keep blood sugar under control also into your meal plan.