urocyon

Looking for something else entirely, I ran across some info I wish I'd had well before this.

From Johns Hopkins' Diabetes and Exercise -- Keeping Your Blood Glucose Levels in Check:

If you have diabetes, you should always check your blood glucose levels twice before exercising: once 30 minutes in advance, and again just before starting. This routine will let you know whether your blood glucose is stable, rising, or dropping.

A safe pre-workout blood glucose level is between 100 mg/dL and 250 mg/dL. If the level is less than 100 mg/dL, have a carbohydrate snack (such as a piece of fruit or three graham crackers) before starting to exercise to prevent hypoglycemia.

People with type 2 diabetes should limit snacking, however, especially if they are exercising to lose weight. If this is the case, your doctor may recommend lowering the dose of your medication on the days that you exercise. If your blood sugar is above 250 mg/dL and you have type 1 diabetes, test your urine for ketones; delay exercise if ketone levels are moderate or high. Regardless of your type of diabetes, do not exercise if your blood glucose levels are 300 mg/dL or higher.

I had figured out to watch for hypos on my own (medicated or no, mine seems really reactive), but had no idea that I should be careful at higher readings. Why is that?

From Mayo Clinic's Diabetes and exercise: When to monitor your blood sugar:

300 mg/dL (16.7 mmol/L) or higher. Your blood sugar may be too high to exercise safely, putting you at risk of ketoacidosis. Postpone your workout until your blood sugar drops to a safe pre-exercise range.

It can also send your blood sugar higher, for a variety of reasons.

This would explain some things. :-| I also doubt that it's very good for your system to have such rapid swings from high to low, which is more likely to happen when mine is pretty high starting out. (The way that makes me feel for a couple of days afterward would also suggest it's not great!)

Now I'm wondering how I managed to miss that, up to this point. If you've got Type 2, medical professionals usually just push exercise (you lazy slob, you!) without much further information--or even finding out how active you are already--but I've done rather a lot of research out of self-preservation. Maybe I managed to skim over that very important information? *scratches head*

This is yet another reminder that I need to get up the nerve to go and try to get more Januvia from the GP. Diet and exercise changes have not made much of a difference in my readings, and I'm suspecting that directly iatrogenic diabetes may well behave differently from "normal" Type 2. :(