The reason there was little research performed in GDM is that many physicians were not sure of the benefits of exercise in a normal pregnancy, let alone a high risk pregnancy such as a diabetic woman. After about 15 years of experiments, from the late 1970's until the early 1990's, the amount of scientific research in the area was increased, and the latest word in sports medicine is that many women are better off performing regular exercise as part of their pregnant routine, than being sedentary over their gestation. It mimics the evidence for people in general, in terms of basic health maintenance.
Exercise in GDM
One of the first studies performed in GDM used bicycles to look at blood sugar response to a controlled exercise situation. Results showed that indeed, these levels did lower in response to exercise. Other studies looked at diet and diet along with exercise and its effects on both short term, and long term blood sugar control. Again, those women who performed regular exercise showed improvement in their blood sugar control, even above that of diet alone. In fact, those exercisers used conditioning regimens in leu of insulin to keep themselves in control during the last half of their pregnancy.
The women in most research studies exercised on aerobic machines, keeping track of work load, and other criteria, such as fetal response to exercise (via heart rate monitoring), maternal heart rate and blood pressure, and of course, blood sugar response. The emphasis of the research also showed that some types of exercise machines, such as the upper body arm crank, and recumbent bike were better tolerated by exercising women, as they did not have any uterine contractions during exercise, compared with other forms of exercise which had a few contraction episodes, prompting an early ceasing of exercise (to be on the safe side).
The Benefits of Walking
Walking is coming into its own as a major health enhancement tool. One of the big questions as to the beneficial aspects of exercise in general is not so much if it is good for healthy people (does exercise make you healthier, or do healthy people naturally gravitate to exercise?), but what are its effects on those with disease.
Walking has been shown to reduce cholesterol levels, have a protective effect from coronary heart disease, reduce body weight, reduce blood pressure, and improve circulation in medical patients. The question to be asked is - what type of effect would it have in diabetes?
Many clinical exercise physiologists report that one of the only types of exercises that they can prescribe to their adult onset diabetic patients is daily walking - since many do not have exercise machines, or belong to a health club. They must therefore be creative in working with "home-based" exercise programs that their patients will adhere to, and benefit their diabetes control.
Walking about 30 minutes after eating has been beneficial in keeping post prandial blood sugars in control for many patients. They feel that they can accomplish a 20 to 30 minute walk 2 or 3 times per day, and over a couple of months, they feel better. Many have reduced their medication levels during their tenure in their walking program.
An application to GDM
How can the pregnant diabetic women accrue the benefits of exercise without an added financial expense, or jeopardizing her or her babies health? Barring any orthopedic limitations, walking 2 or 3 times a day may just be the ticket to enhancing her health, and keeping her blood sugars in check over the last half of her pregnancy. Many women feel that exercise programs become more fatiguing as the third trimester approaches, so even getting out for a walk and increasing circulation is a big help in keeping them feeling good.