Exercise and Diabetes. Sheri R. Colberg

after delivery and progress to doing a combination of moderate and vigorous training to lower her risk of developing T2D later in her lifetime.

      Daily Movement: If possible, CC should continue to engage in as much daily movement as possible to maximize her energy expenditure (to prevent excess weight gain during pregnancy) and to minimize excursions in her blood glucose levels after eating. She should continue standing and taking steps while working and during her leisure time, whenever possible.

      Possible Precautions: Because she is young, CC has limited cardiovascular risk factors. Due to that fact and being pregnant, maximal exercise stress testing is neither necessary nor advisable before starting her exercise program. Because she will not initially be taking insulin or oral medications, her risk of developing hypoglycemia related to exercise is low. She should use a blood glucose monitor to determine the effects of physical activity and dietary changes on her glycemic control.

      Women at high risk for GDM may be able to prevent it with lifestyle management during pregnancy. In those who develop GDM, dietary improvements and regular physical activity are frequently sufficient to manage hyperglycemia, although insulin and oral medications may be used when these changes are not enough. Management of blood glucose levels ensures better pregnancy outcomes and improves the health of both the mother and the fetus. Engaging in 30 min of moderate-intensity physical activity on most, if not all, days of the week has been adopted as a recommendation for all pregnant women.

      Professional Practice Pearls

      • GDM has been increasing in prevalence and is associated with a significantly elevated risk of the woman developing T2D in the next 5–10 years.

      • This transient type of diabetes is usually diagnosed in pregnant women at 24 to 28 weeks of gestation using a 75-g oral glucose challenge (OGTT).

      • Regular exercise participation during pregnancy likely reduces the risk of pregnancy complications like preeclampsia and shortens the duration of active labor.

      • Higher levels of moderate physical activity of any type may reduce the risk of developing GDM during pregnancy and lower blood glucose levels in women who do develop it.

      • A state of insulin resistance caused by placental hormone release during the third trimester greatly increases the pregnant woman’s insulin, resulting in hyperglycemia when pancreatic β-cells are unable to keep up with heightened insulin demands.

      • Diet and exercise are the first line of treatment for GDM, although insulin and oral medications may be considered if lifestyle changes fail to control blood glucose levels.

      • Uncontrolled hyperglycemia is potentially harmful to both mother and fetus, possibly resulting in macrosomic babies and other complications.

      • Most moderate and vigorous aerobic exercise is acceptable during pregnancy with GDM, although some forms of exercise that increase risk of falls and traumatic injury should be avoided.

      • For most healthy women who are not highly active or doing vigorous-intensity activity, moderate-intensity aerobic activity is recommended during pregnancy and postpartum.

      • Women who habitually engage in vigorous or high amounts of activity or strength training can continue these activities during pregnancy and after giving birth.

      • Pregnant women should engage in physical activity on most, if not all, days of the week for best glycemic results.

      • Engaging in 30 min of moderate intensity physical activity on most days of the week, with a target of ≥150 min weekly, is recommended for women with GDM.

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