It should be repeated (if it is not completely obvious) that I am not a healthcare practitioner, nor do I have decades of experience managing diabetes. I am a fitness nut with a penchant for data analysis and scientific research - and a former professional health care consultant - who acquired type 1 diabetes at age 29.
What this means is that I have a knack for research and analysis, but of course no such knack can ever replace a real doctor. I offer my thoughts and ideas mainly as a starting point for your own.
What follows is a description of what works for me, not what is right for everyone.
It may surprise non-diabetics and type 2 diabetics alike that the medical world does not actually consider exercise an effective blood glucose management tool for type 1 diabetics. In Exercise and Sport in Diabetes (2nd Edition), Jean-Jacques Grimm (pp. 25) writes:
Regular exercise in people with diabetes does not necessarily lead to improved control. Indeed, the metabolic disturbances associated with sustained exercise may lead to worsening control unless great care is taken to adjust carbohydrate intake and insulin dosage.... The desire to play, or to become a member of a team, is often more important, and is driven by social reasons and the need not to appear 'different' from the peer group. The aim of the medical team is to allow the diabetic [person] to participate in the sport of his or her choice and to avoid any form of discrimination...[.] The advantages of exercise in type 1 diabetes relate more to its protective cardiovascular effects than to improved glycaemic control. Exercise is not a tool for improving blood glucose control in type 1 diabetes.Emphasis mine.
I provide this quote to illustrate the prevailing opinion among medical practitioners about the role exercise plays in type 1 diabetes. In essence, doctors view exercise as a "good practice" to ward off the effects of a sedentary lifestyle, and also as a means to feel included in society.
My personal experience with doctors reflects this attitude. My diabetes team's efforts - though extremely helpful - seem to be concentrated on allowing me to enjoy exercise as a personal interest, not as a tool to help manage my diabetes. While they have made a herculean effort to keep me exercising at the top of my game, in the end I am left with the feeling that their primary goal is to help me maintain my quality of life. I am extremely thankful to them for helping me with this.
However, my view on the importance exercise in type 1 diabetes differs significantly from that of the medical community. In my view, regular exercise is an important part of managing type 1 diabetes, and the more you exercise, the better off you will be.
That's the thesis statement. Now it requires justification.
Exercise Physiology (Abbreviated) and Using Up Extraneous Blood Sugar
Here's a true story from personal experience. I accidentally exposed my insulin to heat, nullifying its potency. When I injected for my lunch yesterday, the insulin was essentially worthless. My blood sugar shot up from 7mmol/L to 19mmol/L. I took two additional units of insulin two hours later, and my blood sugar was at 20 by about 4pm. Then I went to the gym and hopped on the exercise bike. (Please note: exercise is NOT recommended when your blood sugar is >16mmol/L. I tested negative for blood ketones before exercising, but DO NOT try this at home.) I exercised for about 40 minutes and then went home. When I tested my blood sugar, it was at 8.9mmol/L.
Fact: With moderate cardiovascular exercise, I reduced my blood glucose level by 10mmol/L.
If you ignore all the really interesting scientific aspects of exercise physiology and just focus on the essential workings of things, the human metabolism is not a particularly difficult thing to understand. Here's how it works:
- You consume food.
- Your body converts food into glucose
- The glucose undergoes further chemical processes for storage within individual cells.
- Physical activity triggers a chemical reaction that results in kinetic energy (plus some heat).
- If the activity persists for a few minutes, your body starts combining water and oxygen (more or less) to create additional energy.
- Steps 4 and 5 repeat until you stop moving or until the body reaches a point of exhaustion.
This final "step 7" is why diabetics have to be careful not to have a hypoglycemic episode after exercise. It's not a surplus of insulin, it's a lack of blood glucose caused by the body replenishing its storage.
If it's not clear what I'm getting at yet, let me put a finer point on it: Exercise has a tendency to reduce blood glucose in the short term.
The more you exercise at levels sufficient to instigate this process, the less insulin you need. Because exercise is a volitional act (i.e. you consciously do it), you are therefore consciously controlling your blood glucose levels. You can plan on a workout. You can perform a workout. You can reasonably predict what will happen with your blood sugar. You can be consistent.
Get the picture? Because you control your exercise, you control your blood sugar. So, while the doctors will tell you that this does not improve your blood glucose control, in fact it very literally allows you to control (i.e. manipulate) your own blood sugar in a regular, scheduled, predictable, and frankly enjoyable, way.
Step Two: Doing Even More Exercise
As I have learned from working out twice a day, the more exercise you get, the more these physiological effects kick in. Whereas some doctors and patients may see this as another "obstacle" or another "variable to account for" in their diabetes management, I take a completely different view.
My view is: If the results can be predicted, then the activity can become a tool. One example is the hyperglycemic episode I just mentioned. I knew I was negative for ketones, I knew my insulin had lost its efficacy. I could have gone home, injected a huge corrective bolus, and spent the rest of the night feeling bad about myself. Instead, I used a reliable tool to bring my blood glucose down just as quickly as a dose of rapid-acting insulin analog without having to inject insulin or modify my daily schedule.
So why not exercise once a day? Heck, why not exercise twice a day? Since starting my two-a-day workouts, my blood sugar has never been better. An ideal situation would be to remain active all day long. My muscles would constantly be in a state of metabolizing blood glucose. Assuming I take proper amounts of basal insulin, the more I exercise, the better my glucose control should be.
Knowledge is Power
If it is predictable information, then it is a tool that can be used. Similarly, alcohol is not a "variable" in my diabetes regimen. For the most part, I stay completely away from it. However, if my blood sugar has been high all day, I don't mind having a couple of low-carb alcoholic drinks at dinner time. I do this not to enjoy having a drink, but rather to augment the effects of my mealtime bolus.
The way I see it, why spend all night mildly hyperglycemic - and uncomfortable? Why take huge corrective mealtime boluses? I find these things far more disruptive than using the tools at my disposal. I don't have to manage every mmol/L of blood glucose with a corresponding insulin dose. There is more than one way to skin a cat.
Putting It All Together
In order to gain good control of your blood sugar, my recommendation is to learn as much as you can, try it out, and then adopt a multi-tiered approach.
First of all, take your insulin correctly.
Second of all, use all the tools at your disposal: insulin, exercise, alcohol, dietary adjustments, whatever.
Finally, embrace exercise as a way of life.
I don't have to tell you about the non-diabetes-related health benefits of exercise because you already know. I simply want to reiterate that if you adjust your mental perspective, exercise ceases to be an obstacle to blood sugar control or a "variable to account for." You control when you exercise, therefore you can supplement your diabetes management by giving yourself regular doses of exercise.
And that, in a nutshell, is Ryan's Philosophy of Exercise and Diabetes.