Hack your blood sugar with exercise
Exercise makes your body more insulin-sensitive… which means it keeps your blood sugar lower and helps to prevent diabetes and other chronic health issues associated with hyperinsulinemia and elevated blood sugar.
The CDC recommends getting at least 150 minutes per week of moderate-intensity physical activity. For you math pros out there, that means 30 minutes 5 days per week. But you can break it up more.
It can help to understand how the different types of exercise can improve your blood sugar in terms of timing and intensity level. We’ve learned a lot using continuous glucose monitors over the years while exercising. What follows is what we’ve learned.
How does exercise affect blood sugar levels?
Our blood glucose levels are regulated largely by the hormone insulin. When we eat carbohydrates, our pancreas produces insulin and that stimulates the GLUT4 receptors on our muscle cells (and fat cells) to absorb more glucose, resulting in lower blood sugar. The uptake of glucose by muscle cells is a key player in maintaining glucose homeostasis in our body (balanced blood sugar).
Exercise INCREASES the number of GLUT4 receptors on the muscle cells, increasing their ability to take up glucose both in the presence of and independently of insulin. This effect lasts about 30-40 minutes after the exercise is finished.
However, that exercise will keep on giving! That exercise session will continue to help your muscles respond to insulin for the next 24-48 hours. That means improved insulin sensitivity and better glucose control for up to 2 whole days after a workout. (1)
What does this mean for you? It means exercise can mitigate a high blood sugar meal AND can help you balance your blood sugar for the next 2 days.
How long does it take for exercise to lower blood sugar?
It happens pretty quickly. When I or my patients are using a continuous glucose monitor (CGM) and we see blood sugar spike after a high carbohydrate meal, we like to go for a walk. But frequently, we flop on the couch and watch the blood sugar keep on climbing. In the minutes after we get up and start doing the dishes or walking the dog, we see blood sugar levels level off and start to come down. The effect is immediate.
What kind of exercise lowers blood sugar?
As my friend Garrett Hoyt, Professor of Exercise Physiology at nearby Clark College likes to remind me. “Anything is better than sitting.” The data from the CGM concurs. If you want to lower your blood sugar, get off the couch and do literally anything else. Sure, there are ways to optimize your workouts. But the truly optimal workout is the one you will actually do and do regularly.
Is walking enough to prevent or reverse diabetes?
Yes, yes it is. I volunteer to teach a diabetes prevention class for a local group and walking is the primary exercise our participants take part in. They gradually work up to 150 minutes per week and see big results.
Most people dismiss walking as not being “enough”. It just seems too easy! It’s true that you’ll certainly benefit more if you put some resistance training in there and move your body in a variety of ways. But in terms of balancing blood sugar, and reversing or preventing type 2 diabetes, it certainly will do the trick.
Can walking be Zone 2 training?
One way you can optimize your walk is by monitoring your heart rate. There is a sweet spot called “Zone 2” training where you can walk briskly and it improves the efficiency of your mitochondria and can even increase the number of mitochondria you have. This does wonders for not just your blood sugar, but it increases your cardiovascular fitness considerably. You’ll find your stamina increasing over the months and years by adding this in. Dr. Peter Attia has a great podcast in his interview with Inigo San Millan (if, like me, you’re the type who enjoys 2.5-hr technical podcasts). If you’d rather just get the gist of how to optimize for Zone 2 training, I’ve got a free guide below that you can download that guides you on how to find this heart rate zone and build up to it safely.
The other way you can optimize this walk is by adding weight. “Rucking” is gaining popularity and involves simply wearing a comfortable backpack with some weight in it. (You can call it “rucking” if you want to make it a thing. Or you can just wear a backpack and get on with it.) You can start with a few soup cans or water bottles and gradually add more. Wrap them in a towel so they don’t bounce around or poke you in the back. It means you can keep with the same routine and the same walking partners, but add intensity which improves your strength and stamina rapidly. If you prefer, you can also purchase a weighted vest designed specifically for this purpose. I have personally tried out a few of them and still find a good-fitting backpack with comfortable waist padding to be the best for my body, especially as I start to add on more weight. I talk more about it in the free guide on “Hacking Your Walk”.
What is a good Zone 2 pace?
This differs for everyone!! Finding a good zone 2 pace can be done in a few different ways. I go into detail in this guide on how to hack your walk.
Can weightlifting reduce blood sugar?
More muscle mass 💪 is linked with better blood sugar control. (2)
Adding strength training to your exercise routine has many benefits, and some have to do with blood sugar control. Your muscles are your best glucose “sink”. The more muscle you have and the more you are using them, the more glucose they will take up. That helps you improve insulin sensitivity and keep blood sugar steady.
A study published in the Journal of Basic and Clinical Physiology and Pharmacology showed an inverse association between skeletal muscle mass and blood glucose levels. In other words, more muscle = better blood sugar levels. (3)
In a 2017 study, researchers followed 200,000 people for about 3 years and found those with more muscle mass were also less likely to have diabetes. (4)
Fun fact: When you do exercises that include resistance training, those muscles will be actively taking up far more glucose during exercise. They will then will continue having greater insulin sensitivity for hours, helping you to regulate your blood glucose for the rest of the day. This prolonged effect is why strength training is often compared to long-acting insulin. Targeting the big muscle groups in the legs is a recommendation made by some who have studied the metabolism of people with type 2 diabetes in Japan. (5)
Pro tip: If you have a big eating event coming up later that day (think holiday gatherings), schedule a leg day that morning. It will prime your biggest muscles to be taking up glucose at a higher rate for the rest of the day and turning it into muscle glycogen while keeping your blood sugars in a healthier range.
The American Diabetes Association recommends incorporating strength training into your routine 2-3 times per week. This can take many forms. If you’re a fan of the gym🏋️♀️💪, then go hit the weights and target multiple large muscle groups like your quads, gluts, lats, and pecs. You can also use body-weight exercises, HIIT workouts, and strength-building workouts like Pilates.
Because walking can be a very accessible form of exercise, I like to find easy ways to add strength-building to this activity. Add some lunge steps, add a weighted backpack or find a good set of steps to climb. I put together a whole guide on how to easily hack your walk to increase your strength and stamina. Grab your FREE Hack Your Walk for Better Blood Sugar here.
Does exercise raise blood sugar?
You wouldn’t think so, would you? But yes, it can.
The effect of exercise on blood sugar is mixed and it depends on the intensity of exercise, how you are fueling your workout and your own particular metabolic makeup. As you know now, the muscle cells will be literally sucking the glucose out of your bloodstream helping to lower blood sugar. But the liver’s job is glucose homeostasis. That means its job is to keep your blood sugar levels in the “Goldilocks Zone”… not too high and not too low. If your exercise stimulates a stress response from your body, you will secrete a hormone called adrenaline (epinephrine). This signals the liver to perform gluconeogenesis, where it starts to crank out more glucose into the bloodstream to fuel your muscles, thereby raising blood sugar. For this reason, some people will experience a brief bump in their blood sugar when exercising, especially if it’s a rather intense exercise and/or they are in a fasted state.
This can be information for you, but it’s not a freak-out moment. For example, if you play soccer on a Thursday evening and are the competitive sort, that might spike your adrenaline in a rather exciting way and that will help push you to a better athletic performance. Remember, you’re also exercising and using up that extra glucose!
Interestingly, we see that stress will also bump up glucose levels. My clients sometimes see a stressful conversation cause a brief spike in blood sugar. That’s their fight-of-flight hormone adrenaline kicking in and triggering gluconeogenesis (producing more glucose) to fuel their brain and muscles for the task at hand.
We like to say that a little stress here and there is fine. It can actually be good for you! But chronic stress is not. So if you are using a CGM and notice these stress spikes frequently, it may be time to take a look at that.
If you are watching your stress levels, you might want to use your CGM to inform you of a more appropriate way to work out. People who have been experiencing chronic stress or are post-menopausal might want to minimize the types of workouts that provoke stress hormones (unless they also bring you great joy). I mention that peri- and post-menopause period because women’s bodies tend to deal with stress differently during this time and it is often a time to take better care of our stress-response system. Experiment with pre-fueling your workout or changing the intensity. But mostly, listen to your body and experiment to see what works.
What workout plan is most effective?
Exercise is one of the most powerful levers we have for managing blood sugar. Aside from OVER-exercising, they are all good. However, it appears that some combination of cardiovascular exercise and strength training may be optimal.
I’m going to refer back to the start of this article when I say that the best exercise is the one you will actually do and do regularly. So just start. Make it fun. Make it easy. Make it social and convenient. Create structures that improve your accountability like recruiting friends or hiring a coach for a while. Don’t wait for the perfect situation or the perfect gear or a better season. It NEVER feels like a good day to start exercising. Starting almost always feels hard. Repeating it on week 2 can feel harder. Re-starting after vacation or illness feels like you never did it in the first place. It’s not you. It’s how it is. So let’s stop making it hard. Make it easy. Make it enjoyable.
HACK Your Walk
Learn how to use Zone 2 training to really dial in the benefits of walking as well as other great ways to hack your walks and get my guide to ramping up safely from a sedentary lifestyle all in this free guide.
Final thoughts
There really is no bad way to exercise to improve your blood sugar. As I mentioned earlier, over-exercising is the main caution. Sometimes less is more.
If you love walking, start there and use my free guide to help you level up.
If you don’t have much time, find some short, intense exercises like plyometrics, rope skipping, and pushups in sort of a home circuit that you can complete in 15-20 minutes every day. That will add up to make a huge impact. (I have used this type of mini-workout in the past and it was surprisingly effective!)
If you need accountability and fun, sign up for a class, join a meet-up, or work with a trainer.
Choose something that you’ll actually do. 💙💪🏋️♀️🏃
References
Mul JD, Stanford KI, Hirshman MF, and Goodyear LJ. Exercise and Regulation of Carbohydrate Metabolism Prog Mol Biol Transl Sci. 2015; 135: 17–37.
Haines MS, Leong A, Porneala BC, Meigs JB and Miller KK. Association between muscle mass and diabetes prevalence independent of body fat distribution in adults under 50 years old. Nutrition & Diabetes. 2022;12(29).
Taha M , AlNaam YA , Maqati TA, Almusallam L , Altalib G , Alowfi D and Haider N. Impact of muscle mass on blood glucose level. Journal of Basic and Clinical Physiology and Pharmacology, 2021. https://doi.org/10.1515/jbcpp-2021-0316
Hong S, Chang Y, Jung HS, Yun KE, Shin H and Ryu S. Relative muscle mass and the risk of incident type 2 diabetes: A cohort study, PLoS One. 2017; 12(11): e0188650.S
Hamasaki H, KawashimaY, Adachi H, Moriyama S, Katsuyama H, Sako A, Yanai H. Associations between lower extremity muscle mass and metabolic parameters related to obesity in Japanese obese patients with type 2 diabetes. PeerJ. 2015 May 5;3:e942. doi: 10.7717/peerj.942.eCollection 2015.