Gestational diabetes mellitus (GDM) is a common issue during pregnancy [1]. Physical activity and lifestyle changes are measures aimed at preventing hyperglycemia and excessive weight gain during pregnancy[2]. Overweight, increased abdominal pressure and pregnancy are risk factors for the development of urinary incontinence. Specifically regarding GDM, the number of studies that evaluated the effects of Pilates exercise on gestational diabetes as an adjuvant treatment is scarce[3]. The porpose of this study was to verify the impact of Pilates training on blood glucose, urinary incontinence and maternal weight gain  in women with gestational diabetes mellitus (GDM).

A prospective clinical trial was conducted with participants from a reference hospital in the treatment of high risk pregnancy. The capture of patients occurred from January 2018 to March 2020 and 25 volunteers participated in the study. They were instructed on the objectives of the study, which instruments would be used to conduct their assessment, its benefits and possible health risks. The participants were randomly divided into two independent groups: Pilates group and control group. Ethical approval was obtained from the institutional Ethics Committee (Approval no:1.934.980) and the project was registered in the Brazilian Registry of Clinical Trials (Identifier: RBR- 95xdzh). Participants allocated into the experimental group were submitted to 12 weeks of conventional treatment for GMD associated with supervised Mat Pilates exercises. Subjects allocated into the control group were submitted to 12 weeks of conventional treatment, without the Pilates intervention. Fasting blood glucose was measured with a glucose monitor. Urinary symptoms were assessed using the Short-Form International Consultation on Incontinence Questionnaire (ICQ-SF). Maternal weight gain was obtained from the patient’s medical records. Due to non-parametric pattern of the data, values were expressed as median and interquartile range. Inferential analysis was performed using the Mann-Whitney U test (to assess between groups comparisons) and Wilcoxon test (to assess pre and post-intervention comparisons).

Participants were 35.0(±11) years old at the beginning of the study and both groups consisted exclusively of primigravidae. The groups are similar in terms of anthropometric and clinical variables (age, marital status, pre-intervention weight). Pregnant women in Pilates group benefitted from the physical therapy intervention in relation to fasting (p=0.001) and postprandial glucose (p=0.005). Application of the ICIQ-SF for the evaluation of urinary incontinence showed significant improvement in the Pilates group over the 3 months of follow-up. The score of the participants decreased from 10.0±10.5 to 2.0±5.5 (p=0.005).  In relation to weight gain during pregnancy, during the twelve weeks, there was a significant increase in weight gain in the control group (p=0.002). This difference was not observed in the Pilates group. At baseline, The chi-square test shows that the groups were similar on the percentage of women who were taking oral and injectable medication. (p=0.568). At the end of study, the chi-square test indicated a significant difference between groups in this proportion (p=0.007).

The present results showed greater benefits in the intervention group (Pilates exercises combined with conventional treatment) compared to the control group (conventional treatment consisting of diet, medication, and walking).
Groups were homogeneous in relation of the clinical and anthropometric data (age, initial weight, and marital status). This similarity of the data permits to more clearly analyze the benefits caused by Pilates exercises. The results showed significant improvement in fasting and postprandial blood glucose levels, greater control of weight gain during pregnancy and improved urinary system function.  In addition, the need for injectable medication was lower after the intervention in this group.
Previous studies have shown that physical exercise increases the rate of glucose uptake by the muscle cells during the exercise session and for a few hours after workout . Exercise also improves the action of insulin, promoting glucose uptake into muscle and increasing the use of intracellular fatty acids, which, in turn, improves insulin sensitivity, stimulates glucose uptake and decreases blood glucose levels for more than twenty hours within less than seventy hours . Glucose uptake is also regulates by the duration and intensity of exercise performed. More intense exercises enhances the glucose lowering effect  
According to a systematic review on exercises women with GDM, combined interventions with diet and exercises can have beneficial effects on blood glucose levels, especially postprandial blood glucose level. A recent study showed that supervised exercises started early and maintained during pregnancy could reduce the risk of excessive maternal weight gain during pregnancy and reduce the incidence of GDM. Physical training during pregnancy has a positive effect on health and well-being of the mother-baby binomial, including appropriate maternal weight gain and a birth weight adequate for gestational age. In fact, long-term studies have shown that women who exercise regularly are more likely to have a baby with an appropriate-for-gestational age weight, which decrease the risk of chronic diseases in adulthood, including cardiovascular diseases, obesity and diabetes .  In the present study, Pilates training combined with walking, diet and medication reduced maternal weight gain in the participants, possibly because of increased energy expenditure as a result of the two combined exercise modalities. In addition, the presence of the physical therapist accompanying the activities was a motivating factor for correct execution of the exercises and for strictly following the prescribed diet. 
Urinary incontinence is another common health problem during pregnancy, which is caused by increased abdominal pressure, constipation, weight gain, due to increased intravesical pressure, so that a greater demand for the continence mechanism is required. Application of ICIQ-SF showed incontinence in both groups at baseline; however, improvement of urinary symptoms was only observed in the Pilates group. This finding may be explained by the strengthening of the pelvic floor muscles. This muscle group is a component of the powerhouse, one principle of Pilates training . Another hypothesis is that worsening urinary incontinence in the control group was due to greater weight gain during pregnancy. This hypothesis is more plausible because, although the Pilates technique recommends pelvic floor muscle contraction, there is still no scientific evidence to recommend it as an exercise to treat urinary incontinence. Pelvic floor training is the most suitable type of exercise for the treatment of urinary incontinence.

Supervised Pilates exercises combined with conventional treatment were found to be beneficial for women with GDM, improving blood glucose levels (fasting and postprandial) and urinary incontinence. In addition, Pilates exercises reduced maternal weight gain and the need to use injectable medication. 
This study demonstrates the importance of professional monitoring on the execution of the exercises for a good outcome. More studies are needed to further investigate the Pilates in women with and without DMG, seeking to make those exercises a routine in life of pregnant women.

Melchior H, Kurch-Bek D, Mund M. The Prevalence of gestational diabetes. Dtsch Arztebl Int 2017; 114 (24): 412e8. doi: 10.3238/arztebl.2017.0412.
Bener A, Saleh NM, Al-Hamaq A. Prevalence of gestational diabetes and associated maternal and neonatal complications in a fast-developing community: global comparisons. Int J Womens 2011; 3: 367 and 73. doi: 10.2147/IJWH.S26094
Mazzarino M, Kerr D, Wajswelner H, Morris ME. Pilates method for women's health: systematic review of randomized controlled trials. Arch Phys Med Rehabil.2015; 96 (12): 2231-42.doi: 10.1016/j.apmr.2015.04.005.