Photo: portrait. Caption: Sheri Colberg.
Treatment of diabetes has gone through dramatic changes in the past two decades. Previously, exercise was often overlooked as a “cornerstone” in its treatment as it was difficult to maintain blood sugar levels with the additional variability introduced by physical activity, especially for individuals with type 1 diabetes. However, with blood glucose meters now being readily available and affordable, exercise can be done safely and without fear of severely upsetting an often delicate glucose balance.
Diagnosed with diabetes myself at the age of four in what I call the “Dark Ages” of diabetes (1968), I went through childhood, adolescence, and early adulthood without the benefit of a blood glucose meter. I still participated in a variety of sports and physical activities “pre-meter,” including swimming, running, racquetball, soccer, tennis, weight training, gymnastics, volleyball, cycling, aerobics, dancing, stair master, hiking and backpacking, canoeing, football equipment managing, snow shoeing, cross country and downhill skiing, horseback riding, sailing, snorkeling, and sky diving. I did many of these activities, however, feeling less than my physical best. Since I could not test my blood sugars, tightly managing them to prevent highs and lows was virtually impossible. Growing up I always experienced that exercise of any kind made me feel better overall, although at the time I did not understand human physiology well enough to know why. I felt I had more control over my diabetes when I exercised as well. Consequently, I began exercising regularly on my own and through participation in sports as a young teen-ager and have continued this participation (albeit recreational only at this point) throughout my adulthood.
Not until I had my first blood glucose meter in 1986 did I realize how much
better I felt during exercise when my blood sugars were in a more normal range.
Keeping them normal (with the help of a blood glucose meter) has totally been
a trial-and-error learning process! At the time I got my meter, there were very
few guidelines or books that could offer me any guidance on exercise control.
I did eventually learn to control my blood sugars for various activities; but
every time I tried a new or unusual one, it was like starting over again. Over
time, I met a lot of other active individuals who happened to have diabetes.
I discovered I could learn so much from others' experiences that could hopefully
make my trial-and-error process shorter and easier. With this experience in
mind, I eventually got the idea and motivation for my book, THE DIABETIC ATHLETE
(Human Kinetics, 2001), which covers the basics about exercise, understanding
your body's responses, the effects of insulin and other diabetic medications
on exercise, eating for exercise, exercise guidelines for type 1 and type 2
diabetes, and diabetic regimen changes for over 85 sports and physical activities,
including real-life athlete examples of changes they make.
I have always found that knowledge is power when it comes to managing diabetes. I searched out information for years, which finally resulted in me earning a doctoral degree in Exercise Physiology from the University of California, Berkeley! While you do not need a PhD to understand how your body adapts to exercise, you do need to understand the basics in order to make knowledgeable and safe changes in your diet or medications to get the most out of your workouts. It is my belief this combination of basic (the why of exercise) and experiential (the how of exercise) information can benefit all of us in maintaining blood sugars during any physical endeavor! For example, when you learn to determine what energy systems and fuels your body is using during the exercise, then you can closely predict what your blood sugar response is likely to be and what action you need to take to maintain normal sugars during and following the activity.
It is important to understand the types of medications and regimens you use to either replace insulin or improve its production and action. Your body's level of circulating insulin in your blood will be greatly affected by differing insulin regimens, timing of exercise, and sensitivity to insulin. For example, exercise in the morning usually results in a much smaller decrease in blood sugars compared with later in the day, as your body is more resistant to insulin after fasting overnight. Also, given the variety of insulin regimens and oral diabetic medicines that people use now, strategies that work well for one individual may not work well for another. I, myself, prefer my latest insulin regimen, the insulin infusion pump. Using my insulin pump (the ANIMAS R-1000), I can easily decrease the amount of insulin circulating in my blood by altering the basal rate of insulin delivery, and I can easily compensate for changes in my body's sensitivity to insulin after exercise by choosing a basal rate profile programmed with lower rates.
“Fitness” can be defined many different ways. Probably most important
to overall health is aerobic fitness, or physical conditioning resulting from
prolonged aerobic activities such as brisk walking, jogging, cycling, swimming,
rowing, and aerobic dance. An aerobic exercise program incorporates all the
following components in determining the level of fitness you achieve: the type
of exercise you choose to do (mode), how often (frequency), how long (duration),
and how hard (intensity) you exercise, and your rate of progression. The current
recommendations include doing aerobic exercise a minimum of three to five days
a week, for 20-60 minutes (continuously, or for a minimum of 10 minute sessions
throughout the day), at a moderate intensity (one that feels at least "somewhat
hard"), and progressing as able. Try to incorporate some resistance or
weight training into your regimen two to three days as well to help maintain
your muscle mass and insulin sensitivity. An exercise prescription should be
developed with careful consideration of your health status (diabetes control,
complications, and other health problems), risk factors for cardiovascular disease,
personal goals, and exercise preferences. Also keep in mind that while the intensity
of an activity determines most of the overload on your muscles and your subsequent
fitness gains, it additionally influences your blood sugar responses if you
have diabetes.
If you are already an avid exerciser, then you are aware of most of the benefits of exercise on your physical health and your diabetes control. If you are still in the thinking stage about incorporating regular fitness activities or sports into your lifestyle, then you have a lot of positive changes to anticipate. In addition to the little treats you may be able to allow yourself occasionally after working out, exercise can help you build muscle and lose body fat, suppress your appetite, eat more overall without gaining fat weight, enhance your mood, reduce stress and anxiety levels, increase your overall energy level, improve your immunity, keep your joints and muscles more flexible, and generally improve the quality of your life! Individuals who engage in regular moderate exercise are at lower risk for many chronic health problems as well, including heart disease, obesity, hypertension, type 2 diabetes, certain cancers, and other metabolic disorders.
The usual health benefits of exercise apply to individuals with diabetes as well, perhaps even more than normal. Much of what we attribute to the aging process really results from disuse (for example, muscle atrophy, or loss of flexibility in joints). Diabetes, especially when blood sugars are poorly controlled, accelerates the normal aging process, as well as certain disease processes such as heart disease. Thus, regular exercise can help slow aging and reduce long-term complications associated with poor blood sugar control and diabetes. These diabetes-related benefits can not be understated! Not only can you enjoy your favorite physical activity, but also you can help your diabetes and health too. In fact, regular exercise is the most important activity you can do to slow the aging process, manage your blood sugars, and reduce your risk of diabetic complications.
Diabetic complications are, unfortunately, a reality for many individuals with
diabetes; exercise can usually still be done, but certain precautions may be
needed to make your exercise more safe. If you have any complications such as
eye or heart disease, make sure you follow the exercise guidelines related to
your condition to prevent it from worsening with exercise. It is also important
that you recognize all the potential symptoms of low blood sugar (hypoglycemia),
especially if you have not experienced it often, as its symptoms may differ
during exercise and after you become conditioned. Likewise, remember that proper
warm-ups, cool-downs, and stretching are especially important for diabetic exercisers
for prevention of injuries.
Most of all, lose the excuses! Whether you are interested in
just recreating or want to be a serious competitive athlete, it is time to get
out there and start exercising! Your body will thank you.