Does Exercise Lower Blood Sugar?

Dr Jedha, Host

Hello wonderful people, Dr Jedha here, and thanks for joining me for episode 120.

Today we’re answering a question that confuses a lot of people: Does exercise actually lower blood sugar?

If you’ve ever gone for a walk and checked your blood sugar afterwards… and seen it drop, you’ve probably thought, okay, that’s working.

But then other times, you might exercise—especially something a bit more intense—and your blood sugar actually goes up.

And that’s where the confusion starts.

So which is it? Does exercise lower blood sugar… or raise it?

The answer is: it can do both—but what matters most is what’s happening underneath that.

Because alongside quality nutrition, exercise is a powerful tool to improve blood sugar control. Not just in the moment, but at a deeper metabolic level.

And today, I want to break this down in a really simple way.

We’ll talk about:

• what’s actually happening inside your body when you exercise
  
• why your muscles play such a central role in blood sugar control
  
• and how different types of exercise affect your glucose levels
  

To understand how exercise affects blood sugar, we need to start with one key idea: Your muscles play a major role in controlling your blood sugar.

When you eat carbohydrates, they’re broken down into glucose and released into your bloodstream. From there, that glucose needs to be taken out of the blood and moved into your cells—otherwise, your blood sugar stays elevated. Various cells in the body can uptake glucose but one of the main places that glucose goes is…your muscle. In fact, muscle is the largest site for glucose uptake in the body. So you can think of your muscles as a kind of storage system—a place where glucose is taken in and either used for energy or stored for later.

Now here’s why this matters. If your muscles are working well metabolically, they take up glucose efficiently. Blood sugar stays more stable. But if your muscles are not responding properly—which is what we see in insulin resistance—then that glucose doesn’t get taken up as effectively. And it starts to build up in the bloodstream. So rather than thinking about blood sugar as just a “sugar problem,” it’s more accurate to think of it holistically, because in many ways it’s a muscle problem as well. The better your muscles function… the better your blood sugar control. And this is exactly where exercise becomes so powerful.

So if muscle is so important for controlling blood sugar… what actually goes wrong? This is where insulin resistance comes in. We’ve covered this topic in more detail in episodes 26 and 70, but let’s recap what happens here. Under normal conditions, when you eat and your blood sugar rises, your pancreas releases insulin. Insulin acts like a signal. It tells your muscle cells to open up and take glucose out of the bloodstream. You can think of it like knocking on a door—insulin knocks, and the muscle cell opens the door to let glucose in. But in insulin resistance, that process doesn’t work properly.

The signal is still there—insulin is knocking—but the muscle doesn’t respond as well. The door doesn’t open properly. So glucose stays in the bloodstream instead of moving into the muscle cells where it should be. Now, what’s really interesting—and this is where the science has evolved—is that this isn’t just about body weight or how much fat someone has.

The research shows that insulin resistance is very much about how the muscle is functioning at a cellular level.

Inside the muscle cell, there are systems responsible for:

• transporting glucose into the cell
  
• using it for energy
  
• and storing it effectively
  

When those systems aren’t working well, glucose handling becomes impaired. And that’s why exercise can directly target this problem and restore proper function.

Now let’s take this one step deeper—but keep it simple. Your muscle is not just there for movement. It’s a highly active metabolic organ. As we just shared, inside your muscle cells are systems that control how glucose gets in and how it’s used. One of the key players here is something called a glucose transporter. You can think of these as little “gatekeepers” that move glucose from the bloodstream into the muscle cell. Under normal conditions, insulin helps activate these transporters, allowing glucose to enter the cell. But in insulin resistance, this process becomes less effective. So fewer of these “gates” open, and glucose stays in the bloodstream.

Now here’s where exercise changes everything. When your muscles contract—when you walk, lift weights, squat, garden, do housework, or move in any way—you activate a completely separate pathway. This pathway can move glucose into the muscle without needing insulin to do the job. That’s a very important point. Even if insulin isn’t working well, your muscles can still pull glucose out of the bloodstream during movement, any type of movement – no insulin needed. Under activity, the muscles pull glucose out of the bloodstream independent of insulin. 

So in a very real sense, exercise or movement bypasses part of the problem. And this is exactly why even a short walk can lower blood sugar. You’re directly activating the muscle to take up glucose. Rather than relying only on the hormone insulin to stabilize blood sugar, you now have another mechanism working in your favor. And over time, this doesn’t just work in the moment—it actually helps restore how your muscles respond overall.

Now that we understand how your muscles actively pull glucose out of the bloodstream during movement, let’s break this into two really practical parts.

Exercise helps blood sugar in two different ways:

• immediately
  
• and over time
  

Let’s start with the immediate effect. When you move your body—whether that’s walking, doing housework, or exercising—your muscles contract. And as we just talked about, those contractions allow glucose to move out of the bloodstream and into the muscle, even without insulin working perfectly. This is why you can go for a walk after a meal and actually see your blood sugar come down. Your muscles are actively clearing glucose from the blood. Now this effect can happen quite quickly—sometimes within minutes. This can be very effective to help reduce post-meal blood glucose levels after a meal. The immediate effects can be powerful. But it doesn’t stop there. There’s also a longer-term effect that’s just as important.

With regular exercise, your muscles become more sensitive to insulin again. That “door” we talked about earlier starts to respond better.

So over time:

• your body needs less insulin
  
• your muscles take up glucose more efficiently
  
• and your overall blood sugar levels improve
  

So rather than just thinking, “Did my blood sugar drop after this workout?”

It’s more helpful to think: “Am I improving how my body handles glucose overall?”

Because that’s where the real benefit is. Exercise is not just a quick fix, in the moment—it’s actually helping to repair the underlying issue. And this is why consistency matters far more than intensity or perfection.

Now the next question is: What type of exercise actually works best for blood sugar?

And the answer is—not one type, but different types of exercise work in different ways. First, walking or light movement, which we covered in episode 89,  is one of the simplest and most effective strategies—especially after meals. When you walk after eating, your muscles immediately start using glucose from that meal. So instead of that glucose sitting in your bloodstream and causing a spike, it’s being taken up and used. This is why even 10 to 15 minutes of walking after a meal can make a noticeable difference. It’s simple, but very effective. 

Next, resistance training—things like weights, bodyweight exercises, or strength-based movements. This works a little differently. Resistance training helps you build and maintain muscle. And remember, muscle is where glucose is stored. So the more muscle you have, the greater your capacity to take up and store glucose. Over time, this improves insulin sensitivity and overall blood sugar control. So resistance training is more of a long-term strategy—but an important one.

Then we have higher intensity exercise. This is where things can sometimes look a bit confusing. Higher intensity exercise can sometimes cause a temporary rise in blood sugar. But that doesn’t mean it’s harmful. What’s happening is your body is releasing extra glucose into the bloodstream to fuel that activity. But over time, this type of exercise still improves how your body uses glucose and responds to insulin. So again, short-term response… versus long-term benefit.

Another important point to make is that for someone who’s just starting out with exercise, the body can respond a little differently at first. Even moderate activity can trigger a release of glucose into the bloodstream, because the body is preparing to fuel that movement. But the muscles may not yet be as efficient at using that glucose—so you might see a temporary blood sugar rise. Again, a short-term response for a long-term benefit. It’s not a sign that exercise isn’t working—it’s often a sign your body is still adapting.

So, when it comes to exercise, all types have benefits. In fact, any movement has benefits for blood sugar control.  You don’t need to rely on just one type of exercise. Walking helps immediately. Resistance training builds capacity, restores and maintains function. Higher intensity exercise improves overall metabolic function. They all work—just in slightly different ways. And again, ANY movement has benefits whether that be yoga, housework, gardening, etc, Movement means muscle function is activated, which helps utilize glucose.

So, it’s easy to understand the science—but what really matters is what you do day to day. You need to actually use this in a practical way, including movement and exercise as part of your daily routine. The first and simplest strategy is to move after meals. We covered how walking helps with this in episode 89.  Even 10 to 15 minutes of walking after eating can help lower the rise in blood sugar from that meal. Go for a walk around the block, or if you can’t get outside, walk on the spot—you can even do this while watching TV so there’s no excuses here. Likewise, any activity after meals can help. For instance, after your meals you could do a few things around the house, do a few bodyweight squats, high knee lifts on the spot—anything to get your body moving within about 30 minutes post meal will help to reduce glucose spikes. 

The second piece of the puzzle is to include some form of resistance or strength-based activity a few times per week. This doesn’t have to mean going to a gym. It could be bodyweight exercises at home, light weights or resistance bands workouts. The goal here is to support and maintain muscle, because that directly improves how your body handles glucose over time. And, it’s important to realize that as we age we lose muscle, so we want to proactively build or preserve as much muscle mass as possible, to help with glucose control and our overall metabolic health. 

The third piece of the puzzle is simply consistency. Not intensity. Not perfection. Consistency. Because every time you move, you are activating that pathway in the muscle that helps pull glucose out of the bloodstream.

Rather than thinking in terms of: “I need to do the perfect workout” or “I have to push myself.” It’s more helpful to think: “How can I build more movement into my day?” Because it all adds up. And importantly, this is something you can start wherever you are. Even small amounts of movement can begin to improve how your body responds.

So… if you take one thing away from this episode, it’s this: Exercise directly improves blood sugar control—and it works at the level that actually matters, which is your muscle.

Every time you move, your muscles are pulling glucose out of the bloodstream. And over time, they become better at responding to insulin and handling glucose more effectively. So even if you don’t always see an immediate drop…or you occasionally see a rise…That doesn’t mean it’s not working. It means your body is responding—and adapting. Because this isn’t just about what happens in a single workout. It’s about what happens over days, weeks, and months of consistent movement. 

Focus on building movement into your routine in a way that you can maintain. Every single day, move your body.  Because every step, every bit of resistance work, every session—it all contributes to improving how your body manages blood sugar. And that’s where the real impact is, especially when combined with a quality nutrition plan.

So there you have it, wonderful people. It’s up to you to make a move. 

Thanks for joining me and see you in the next episode. 

Dr Jedha, over and out.