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Exercise at any time is good for your overall health and well-being. But a growing body of research shows that walking after a meal is especially beneficial for your metabolic health—particularly if your post-meal walk falls within a specific “sweet spot” window.
Metabolic health describes how well your body generates and uses energy at the cellular level. Those who are metabolically healthy tend to feel more energetic, have better memory function, and are more able to burn fat and maintain a healthy weight, among many other benefits.
One key indicator of your body’s metabolic health is its ability to efficiently process glucose, the sugar in your blood that comes from the foods you eat. Eating foods with carbohydrates raises our blood sugar. Still, in general, we want to maintain stable glucose for short-term benefits (like avoiding a post-meal energy crash) and long-term benefits (like helping avoid chronic disease).
Choosing whole foods low in refined carbohydrates and sugar can help with that steady blood sugar, but so can exercise since muscles can use glucose from the bloodstream for energy. Recent research suggests a simple walk after a meal can help blunt the immediate glucose spike after that meal and significantly lower overall levels of insulin, a hormone that helps our cells take up glucose but can be damaging if our bodies produce too much. That’s a good thing for long-term metabolic health.
The Relationship Between Exercise and Glucose
Scientists are still studying all the factors that regulate glucose delivery from the bloodstream to muscle cells, but one thing is certain: Our muscles are glucose processing workhorses.
- At the tissue level, muscle contraction increases heart rate and respiration, which sends more blood to working muscles.
- At the cellular level, when your muscles contract, or shorten, they’re able to take in more glucose through muscle membranes.
- At the molecular level, exercise changes the behavior of enzymes involved in glucose metabolism. First, body movement activates adenosine monophosphate activated protein kinase (AMPK), a stimulator for glucose uptake. The increase in AMPK activity deactivates TCB1D1, a protein that spurs the transfer of glucose transporter type 4 (GLUT4), which docks into cell membranes, allowing glucose to pass into the cell.
Put simply, when you exercise, muscle membranes become more efficient at absorbing glucose, the heart pumps more glucose-containing blood to your muscles, and changes in chemical enzymes further aid glucose transport. With all of these mechanisms occurring simultaneously, our muscle cells enjoy the glucose they need to power a workout, and our blood glucose levels drop.
What’s more, while your body typically needs to release insulin to get glucose into cells, exercise allows muscle tissue to absorb glucose without insulin. Reducing insulin secretion in response to glucose rises after meals is a good thing, as we want to keep insulin levels under control as much as possible. High insulin levels (hyperinsulinemia) over time can lead to insulin resistance.
Walking After Eating: When Is the Right Time to Move?
The short answer: It depends. The current body of evidence suggests that healthy people can reap the benefits of a post-meal walk for up to 6 hours after eating, but some people might have reason to exercise sooner.
In a 2021 review of 51 studies published in Sports Medicine, researchers found that doing a single bout of at least 30 minutes of continuous cardio within 6 hours of eating decreased glucose and insulin levels in the six hours after a meal (the postprandial period) compared to being at rest. The paper is novel in that it examined the glucose and insulin responses of only people without a diagnosed metabolic disorder.
The researchers observed these benefits when study participants exercised in the postprandial state (the 6 hours following a meal) but not in the fasted state (more than six hours after eating).
Meanwhile, other evidence suggests that exercising in the “mid postprandial phase” of the feeding cycle (which tends to fall 30 to 120 minutes after eating) most effectively tames a glucose peak. A 2016 review examined 39 papers, which encompassed a collective 615 participants with various metabolic conditions (such as diabetes, prediabetes, and obesity) and people without any diagnosed conditions. The study authors concluded that exercising 30 to 45 minutes after eating is the ideal time to curb glucose levels.
The reason exercise timing matters has to do with the mechanics of glucose uptake described earlier. When you eat, glucose enters your bloodstream from your gut, raising the blood sugar concentration. But when you exercise right away, that glucose is quickly taken up by muscle tissue, bringing your blood sugar levels back down. Your body’s glycemic balance depends on how quickly meal-derived glucose arrives in the blood and the rate at which exercise draws upon this fuel.
For that reason, the type of food you eat can also affect the ideal timing for your workout. A 2019 randomized clinical trial looked at the optimal window for exercise around eating a 500-calorie liquid meal, as liquid is absorbed by the body faster than solid food. Researchers recruited 48 adults to examine how their glucose response changed when they performed 30 minutes of physical activity at various times before or after eating, or no exercise at all.
In this case, moving immediately after the meal was the clear winner: Walking and bodyweight exercises improved glucose levels. Even standing up right after a meal offered a minor benefit. Participants saw no impact on glucose exposure or variability when exercising before, 30 minutes after, or 2 hours after consumption. So, if you’re having a smoothie for breakfast or lunch, or fast-absorbing carbohydrates (think fruit, starchy foods, or anything processed like foods containing sugar or refined flour), you may want to get moving right away.
Do Intensity and Duration of Walking After Eating Matter?
Low- to moderate-intensity activity, like brisk walking, appears best for keeping glucose levels in check after eating. One reason for this is that walking depends on aerobic metabolism, which draws upon glucose in combination with fatty acids and protein in the body. So when you take a walk after eating, you burn through glucose at a moderate rate to help curb a spike without prompting the production of additional glucose.
On the other hand, high-intensity exercise relies on anaerobic metabolism, which draws upon glucose as its only fuel source. Because glucose availability in muscles is limited, vigorous exercise stimulates hormones that prompt the liver to produce glucose to meet the rising energy demand, resulting in elevated blood glucose.
Related article: Optimize your exercise performance by tracking glucose
This dynamic is illustrated in two studies in the 2016 research synthesis exploring the effect of exercise intensity on glucose surges. One incorporated exercise at 45 minutes after a meal; the other, an hour. In both studies, when participants exerted themselves beyond 71 percent of their VO2 max (an effort level that qualifies for high-intensity), their glucose levels rose 20 minutes into the hour-long session. On the other hand, when participants kept their intensity to 50 percent of their VO2 max (a more moderate effort), participants’ glucose levels did not rise. (How much of that rise depends on the meal consumed is unclear. Another study found that high-intensity exercise done in a fasted state had effectively no impact on glucose levels.)
The study review’s authors concluded that the best post-meal exercise intensity and duration to keep glucose levels in check is to start something like a brisk walk within 30 minutes of a meal and continue for up to an hour. This is consistent with the findings in the 2021 review of research published in Sports Medicine, which focused on the glucose-stabilizing effects of a single session of steady-state cardio for 30 minutes or longer.
What If You Don’t Have 30 Minutes?
Walking for 30 minutes after a meal might not fit into your schedule, especially if you’re already doing other workouts during the week. Good news: Shorter bouts of low-intensity movement are also effective at taming glucose surges.
A randomized crossover trial compared post-meal metabolic factors, such as plasma glucose and insulin concentrations. Researchers worked with 70 adult participants, who completed three interventions, all lasting nine hours:
- Continuous sitting for nine hours
- Sitting for 15 minutes, walking for 30 minutes, and then sitting for another eight and a half hours
- Sitting for eight and a half hours, but with 100-second bursts of treadmill walking every 30 minutes (a total of 30 minutes treadmill walking, plus sitting for eight and a half hours)
During the nine hours, all participants for all interventions drank a meal-replacement beverage at one, four, and seven hours. Participants in group #2 performed their 30 minutes of continuous exercise before consuming the first meal-replacement beverage.
Those who took the shorter activity breaks more regularly lowered both plasma glucose and plasma insulin compared to both prolonged sitting and the single bout of continuous activity.
Researchers posit that the smaller, more regular doses of activity may increase muscle permeability and keep GLUT4 ready for rapidly transporting glucose to fuel cells. Put simply: With regular low-intensity exercise, your muscles absorb excess glucose from your bloodstream more frequently, even if it’s done for brief periods (only 100 seconds every half hour!)
What This Means for You
The most important takeaway is simple: Whenever possible, move your body after eating. Doing this helps mobilize post-meal glucose to fuel physical activity and curb the spike you might experience if you were inactive.
- Walking for 30 minutes within 6 hours of eating is a good standard for healthy people, though sooner is likely better.
- After finishing a meal, taking a brisk walk for about 30 minutes is an excellent habit to adopt. Alternatively, just walking briskly for a minute and a half every half hour has significant benefits on overall daily glucose and insulin levels.
- Set a timer for every half hour to remind yourself to get up for just a minute or two to move.
Most importantly, don’t let concerns about timing, intensity, and duration stop you from making an effort. When you regularly choose to move after eating instead of spending hours at your desk or on the couch, you build a habit that supports metabolic health immediately and in the future.