Guidelines for exercise during normal pregnancy and gestational diabetes: a review of international recommendations.

OBJECTIVE: Τo summarize and present the main guidelines for exercise during normal pregnancy and pregnancy complicated by gestational diabetes mellitus (GDM).

METHODS: Relevant guidelines were retrieved through the electronic databases PubMed (MEDLINE), CENTRAL (Cochrane), and Embase; reference sections of the retrieved publications; proceedings of the main congresses in the field; and websites of relevant organizations published during the years 2000-2018.

RESULTS: All guidelines recommend aerobic training from 60 to 150 min/week, with an upper limit of 30 min/day. Exercise is safe, even on a daily basis. Resistance exercise is suggested by five national guidelines (Australia, Canada, Denmark, Norway, and the UK). Discrepancies exist regarding the recommended intensity of exercise. Canada, Japan, Spain, and the UK use both objective (heart rate and maximum oxygen consumption) and subjective criteria (Borg's Scale and talk test) to determine the effectiveness and safety of exercise. Only Canada provides specific recommendations, according to the woman's age and level of physical condition. Women with GDM on no insulin treatment do not need to take extra precautions during exercise. However, due to their condition of hyperglycemia, they must comply with the recommendation issued for type 2 diabetes. The prescription and supervision of exercise should be carried out in a similar way as for uncomplicated pregnancies. Finally, women with GDM on insulin treatment need to follow the same recommendations as for those for pregnant women with type 1 diabetes.

CONCLUSION: Health professionals must be informed about the correct planning and execution of physical exercise programs so as to safely achieve the maximum effectiveness of exercise-induced health-related benefits in pregnant women.