Can exercise trigger the Somogyi effect?

I had a really active weekend last weekend - snowshoed for an hour on Saturday, then got lost cross country skiing on Sunday and what was supposed to be an easy 30-45 minute ski turned into an hour and forty minutes. It wasn’t horrible, I didn’t feel excessively fatigued or anything afterwards, and I enjoyed really good blood glucose control for the rest of the day.

Imagine my surprise when I woke up the next morning with a blood sugar of 137 (it’s usually between 100-120 lately). It stayed high all day.

Nothing but the exercise was particularly different - I didn’t binge on carbs or anything.

I was just reading about the Somogyi effect, and I’m wondering if that’s what happened to me. Could it be that the exercise pushed my blood sugars down far enough to trigger this? I’ve checked my blood sugar a couple of times in the middle of the night (but not that night unfortunately) and it’s always been fine. I have woken up a few times sweaty and with a rapid heart rate… which I just read can be a sign of a rebound.

I’d assumed I wasn’t having Somogyi effect because my glucose was fine, but if I was already in the rebound stage then that’s not a real indicator.

If it was Somogyi, should I make sure to have a snack before bed on the days that I exercise a lot? Lower the Lantus (currently the only insulin I take is bedtime Lantus)?

I will be asking my Endo about this, but unfortunately he’s out of town until February :frowning:

I don’t know if that would qualify, but I don’t know enough about T2. I’m T1 and when I’ve had it, I’ve woken up in the 300’s, 400’s and even 500’s. I was having major issues with it before I got my CGM, but never caught the lows when I did random overnight checks. After I saw the pattern on my CGM, I adjusted my basal rates and fixed it.

Either way, how you address it - snacks or adjusting insulin - is up to you and you’re comfort level making those adjustments on your own. Even if your doctor is out of town, surely he has someone covering for him that could give you some recommendations or there’s a CDE who could help you. I would try that first, especially since you’ve only been at this for a couple of months.

Heh. I live in a small town. There is ONE Endo in town, and he’s the guy I go to. I’m not even all that confident that he’ll know what the Somogyi effect is.

I already talked to the CDEs, they have no answers for me.

I’m going to a team of specialists out of town in a month… and hoping that I’ll get much better care with them.

Does anyone know if Somogyi is something that, if you have it, happens every night reliably? Or can it happen only occasionally? I’m not having much luck finding anything but very lightweight info on it.

Do you have a primary care doctor. You can just explain that you had an active day, you woke up higher than normal the next day, and you think you might be dropping low in the middle of the night and rebounding. They may or may not be familiar with the phenomenon’s term, but that doesn’t mean they don’t know the phenomenon. Or just try eating a snack and see what happens. Waking up sweaty with a rapid heart rate would likely be a low BG, but you won’t know unless you keep your meter next to your bed and make a point to check if that happens again.

It can be a regular thing if something about one’s D management is off or it can be an occasional thing.

I wouldn’t get so concerned about it though, especially if it just happened the one time. Maybe it was just a fluky thing. Or hormones. Talk to the doctor about it when you see him next, or make sure you ask about it when you see the specialist next month. If it just happened that one time, it doesn’t sound like something that can’t wait, and either way, you don’t have enough info about what happened to determine what it was so unless it replicates itself and you get additional info and/or see a pattern, it’s probably not worth getting too worried about.


Please do me and others a favor … speaka da ingliss! I-) I have no idea what you were talking about and, maybe, I need to know that this “effect” is.

Lois La Rose
Milwaukee, WI

Somogyi Effect

As I suggested initially, it’s more commonly associated with T1 because it’s of concern to people who have little endogenous insulin production, relying on insulin injections or pumps and are thus susceptible to extremely high BG’s.

I’m listed here as Type 2, but, at least in my mind, that diagnosis is up in the air. From my reading, I seem a lot more like adult onset Type 1, or perhaps LADA. That’s another reason why I’m going to the specialists, I want a second opinion and if I am indeed Type 2, some answers about why I seemingly fit none of the stuff I read about Type 2. (not overweight, eat well, very active, very little response to Metformin, very good response to very little Lantus, etc. etc.)

Back on track… thanks a lot for your reply on the Somagyi effect. I’m not really all that worried about it, more curious. I have checked my BG at least once while I was feeling sweaty at night, and it was fine. I am going to start keeping my kit next to my bed, though, because I find that if I have to get up and walk across the house to get it I’m much less likely to take it in the middle of the night.

I also read that rapid heart beat/night sweatiness is not only a sign of hypoglycemia, but also a sign of rebound. Sheesh, can’t these two conditions get their symptoms straight?!?

I remember Somogyi references in the Think Like a Pancreas book by Gary Ssomething if you can get your hands on that or reference it.

Everyone is different, but I’ve never heard of anyone having those symptoms if their BG is rebounding. I don’t know - maybe someone here has had that experience though. If I’ve been low and my BG is headed up, I might get really tired and/or get a headache. Something about being low and heading back up makes me want to take a nap though.

I really should get a meter to keep by my bed, but I just make sure I bring my meter up with me at night. I didn’t used to be in that habit, and like you, if it isn’t there, I’m not likely to get up and find it. Even if it is there, if I can tell without a doubt that I’m low, I’ll just eat glucose tabs without checking - not the best idea really, but I hate to have my sleep interrupted.

Dr. Bernstein says it is a ficticious effect so we should be careful as he is very knowledgeable. I cannot comment since I have not experienced this efect.

Yes, a lot of exercise makes BG control much better.

I also makes the blood circulation much better too, so you wonder if the exercise made you use up the Lantus quicker that on less intense days.

Still the numbers were not very high

If you would have gone low the day you did a lot of exercise you would wake up hot and sweaty with a rapid heart rate. so you would know that it went low. The body not enjoying this could have ordered the liver to spew out more glucose the next day.

Yeah, I have this book, and that’s what made me think of the Somogyi effect.

He lists a bunch of symptoms, but doesn’t differentiate between symptoms of hypo and symptoms of rebound.

He does mention some pretty high blood glucose numbers - like in the 300s - so maybe my relatively small jump isn’t high enough to qualify for Somogyi. But that’s just an assumption, nowhere can I find anything that says that huge jumps are required.

I think Dr. B is a hack for the most part. There’s a section on the Somogyi Effect in the ADA’s Medical Management of Type 1 Diabetes. I have an older edition, copyright 1998, but I’m not inclined to think the info on this has changed because it’s an established physiological phenomenon. From page 142:

“The phenomenon originates during hypoglycemia, with the secretion of counterregulatory hormones (glucagon, epinephrine, growth hormone, and cortisol). This hormonal surge, together with decreasing insulin levels, leaves counterregulatory hormones relatively unopposed. Hepatic glucose production is stimulated, thereby raising blood glucose levels. These hormones may cause some insulin resistance for a 12- to 48-h period… As a general rule, when hyperglycemia does not respond as expected to treatment adjustments, undetected hypoglycemia and rebound hyperglycemia should be considered as a possible explanation. Rather than increasing insulin dosage day after day, the clinician who suspects rebound hyperglycemia should endeavor to detect (via SMBG) and avoid the initiating hypoglycemic event.”

SMBG= self-monitoring blood glucose

Is this not a bit harsh To call Dr. Bernstein a hack.

Anyone that has had diabetes for more than 50 years and has stayed vigourous is a genius in my book.

There are a good number of folks who’ve had T1 for 50+ years and are doing well - not necessarily having done things his way. He just happened to write a book about what he thinks worked for him and is now a demi-god bazillionaire because of it.

I’ve had it for 30, and I’m doing really well considering I spent almost 20 of those years not taking care of myself. I’ve reversed some of the damage I did by doing things quite different from what Bernstein recommends so after I write my book about all things in moderation and valuing quality of life over severe restrictions, I’ll come back and claim my genius pin.

I’m with Lee Ann. Though I’ve only been dealing with diabetes a few months, it seems to me that it’s no great revelation that if you severely restrict carbs, you won’t have issues with sugar. After all, the carbs are what makes the sugar go up!

The vast majority of health care professionals believe that severely restricting carbs can adversely affect your kidneys and other organs. Also, people on low-carb diets eat a large amount of high-fat food, which leads to heart problems. It’s not a balanced diet.

I realize that some people have such a difficult time controlling blood sugar that an ultra-low-carb diet is their only choice, and I respect that. But for the majority of us, it should be the last thing we try, not the first. Ideally, one should be able to eat a balanced, healthy diet and also keep their blood sugar in control. I personally know a lot of diabetics - both in person, and through boards like this - that do that just fine. I hope to be one of them.

Of course if you are a very mild diabetic and your pancreas is still working and you have little insulin resistance and you can reduce weight and keep the BG in the normal range at all times then eats carbs, no problem. 10 years ago I did just that. Although I was never able to get the BG quite into the normal range with infinite exercise and weight lost and this wrecked the pancreas over time. So now BG control is a nightmare. Being a fresh diabetic on insulin may help you to eat carbs and keep the pancreas alive and being young weight gain is much less of a problem. However keep this in mind as time goes by.

The major cause for bad lipids is having high blood sugars. The seconds most important factor for good lipids is exercise and diet is of tertiary importance.

What you have to remember is that if your BG is bottoming out, it’s an insulin reaction.I think the symptoms you describe are the indications that your BG is too low, not the actual rebound. Generally, my rebounds hit their peak (if I haven’t already caught it) 3-4 hours after the fact. 1-2 hours, my BG will be deceptively normal which lulls me into a false sense of security!


If I had to guess, (remember I got my medical degree on the back of a match book) I would say no / maybe. I have had many many rebounds in my life and usually it is far more pronounced. Her is why. A rebound usually follows pretty extreme lows. Your note does not say you experienced a prolonged or deep low followed by a sustained high. This looks more like a ripple than a Somogyi effect. If my blood sugar had fluctuated as you describe I would have called it an abnormality.

Rick (the crackerjack prize md) Phillips

Hi Barbra,
I’m trying to figure this out too. I’ve noticed on a few occasions that exercise raises my blood sugar. Not crazy high or anything, but higher than it was before I exercised. I just posted a question about it. I don’t THINK it is a rebound from going low, but maybe some kind of adrenalin release?

It sounds like you’re doing a good job of staying in shape. Good luck, and let’s hope we can all figure this out.

Hi Barbra,

As a Vermont native who’s been T1 for 47 years, I find myself wondering about how chilled you may have gotten during skiing, especially since you stayed out longer than you’d planned. For me, getting even a little chilled serves as what I think of as one of my “external insults.” My BGs shoot up and remain there, often for as long as 6-8 hrs, and don’t yield readily to additional insulin. I consider this to be a classic rebound, very similar in degree and duration to a rebound following severe hypoglycemia, an “internal insult.” At a point in your life when your metabolism is working less and less efficiently, perhaps you’re no longer handling cold temperatures as you once did…??