Findings from two recent studies exploring Exercise, Pregnancy and Diabetes

Some pregnant readers may wonder, ‘Is it safe to exercise?’ Others may also have gestational diabetes mellitus (GDM) and could be contemplating how exercise might influence their condition. Two recent publications address these concerns.

In an article for the British Journal of Sports Medicine entitled ‘Exercise during pregnancy. A narrative review asking: what do we know?’ researchers conclude: ‘In the absence of obstetric complications, the healthy pregnant body is able to cope with the physiological demands imposed by moderate exercise.

Moderate exercise is not a risk factor for foetal and maternal pregnancy outcomes. A supervised programme of moderate exercise throughout pregnancy may be recommended by health professionals to attenuate the risk of pregnancy alterations.’ They also cite studies which have demonstrated that exercise during pregnancy improves depression-related symptoms, and that ‘… the cardio respiratory response to acute exercise in pregnant women who were physically active throughout pregnancy was better than in women who remained inactive during gestation.’

Diabetes occurs when there is too much glucose in the blood and it cannot be controlled by the hormone insulin. GDM is a form of diabetes that can affect women during pregnancy, typically developing after 28 weeks and usually disappearing after birth. But women with GDM do also have an increased risk of developing type 2 diabetes.

Spanish-Canadian Study

It’s known that exercise is an essential element for glucose metabolic control and may prevent GDM, but the type, duration and intensity of exercise during pregnancy to prevent GDM are not fully defined. This was addressed in a joint Spanish-Canadian study in which researchers investigated the effects of a combined exercise programme on land and water that used aerobic and muscle-toning activities.

A total of 257 pregnant women from Spain, all 10-12 weeks pregnant and with an average age of 33, were split into two groups. The intervention group, which consisted of 101 women, exercised for 60 and 50 min on land and in water, respectively, three times a week. The control group of 156 women received the usual standard care.

Each land session included a gradual 10-minute warm-up, aerobics (20 min); resistance exercises (12 min); pelvic floor exercises (10 min) and stretching (8 min). Each aquatic session included a 10-minute warm-up; a core session of swimming laps, step climbs, lunges and strength exercises in the water (30 min); and stretching (10 min). All sessions were supervised by a qualified fitness instructor.

Positive Results

The results of the study are summed up by the title of the article published in the journal Medicine & Science in Sports & Exercise: ‘Exercise Is Associated with a Reduction in Gestational Diabetes Mellitus’. The prevalence of GDM in the exercising group was 1%, compared to a prevalence of 8.8% in the control group. The researchers cite studies reporting that physical exercise reduced the prevalence of GDM in women.

However, they also refer to one investigation which began an exercise trial with women at 18 to 22 weeks pregnant and found no difference between exercising and non exercising groups. They suggest: ‘It may be that early exercise intervention may be key to GDM prevention.’ The Spanish researchers also point to reports showing ‘… better control of glucose metabolism in pregnant women who exercise compared to those who remain sedentary.’

What does this mean for you?

In 2010 Paula Radcliffe ran 10km in just over 45 min while she was seven months pregnant. RF is not suggesting that this is something for all pregnant women to aim at. Rather, with the evidence clear that in the absence of obstetric complications moderate exercise can be beneficial to pregnant women it seems sensible to keep active, and health professionals can advise how best to do it.