What does APS stand for in pregnancy?

Until the end of the 1950s, medical prejudices made physical and sporting activity (APS) and femininity incompatible. Today, around 37% of members of sports federations are women. The latter have also invested in high-level sport to represent nearly 45% of the athletes present at the Rio Olympic Games in 2016.

Women in sport are becoming a subject of study, especially since we must take into account the changes that accompany their lives: periods, pregnancies, menopause. Today, many associations recommend APS to pregnant women. It has thus been demonstrated that practicing APS brings benefits to the mother and the fetus.

Three studies conclude that there is no association between spontaneous abortion or placental implantation problems and the practice of APS (1-3).

According to Hjollund et al., this risk is present if exercise is intensely continued during the implantation period (i.e. 6 to 9 days after ovulation) (4). Regarding the risk of uterine contraction, in a pilot study, a tocometric recording carried out on 10 pregnant women during the practice of APS shows that the changes in uterine activity are minimal (5), and even that the number of false labors decreases (6).

Juhl's results (7) confirm those of previous studies showing that PSA significantly reduces the risk of preterm birth. These results are in line with those of Leiferman (8), who demonstrated from 1,699 single, uncomplicated pregnancies that intense PSA during the first and second trimesters did not increase the risk of preterm birth, but on the contrary reduced it by 20 to 25%.

All studies therefore indicate at least the absence of risk of premature birth. The only element reflecting an increased risk is the standing position maintained for more than 5 hours per day and the carrying of heavy loads (9).

Only scuba diving can be responsible for congenital anomalies. Indeed, in the event of a decompression accident, it is impossible to know the brain state of the fetus. Furthermore, according to the recommendations of most authors, pregnant women should not be exposed to temperatures likely to increase their body temperature above 39 or 39.5 °C during the first three months of pregnancy, because this would have a teratogenic effect on the fetus. After an exhaustive review of the scientific literature on the subject, the Canadian Academy of Sports Medicine states that, in women who have established their own PSA rhythm during pregnancy, the increase in temperature is not significant enough to be harmful to the child.

Regular physical activity is important for both physical and mental health. The mechanisms underlying these effects are not fully understood, but compared to their sedentary counterparts, pregnant women who engaged in physical activity throughout their pregnancy were less likely to experience stress, insomnia, anxiety, and depression (10). Recent studies have also shown that these women had greater feelings of well-being and self-satisfaction, and had a better quality of life (11, 12).

Practicing a PSA helps to contain weight gain, but its influence is limited by the progress of the pregnancy and the duration of the exercise. Clapp (13) thus demonstrates a lesser weight gain and a faster return to the previous weight when the PSA is continued during the third trimester by prioritizing the duration of the exercise rather than its intensity. Moderate and regular PSA during pregnancy also helps prevent the later risk of being overweight or even obese. And in obese women, a weight gain of 11 to 15 kg during pregnancy quadruples the risk of increasing the initial weight one year postpartum.

Low back pain is present in 24 to 56% of pregnant women. Relieving it through APS is therefore of prime importance. Several studies have questioned women during their pregnancy after a training program (14-17). The practice of APS (aerobics, flexibility and muscle strengthening, aquatic gymnastics and gentle gymnastics) reduces the intensity of lumbopelvic pain during pregnancy.

APS induces an improvement in insulin sensitivity and better glucose tolerance. It thus helps prevent and manage gestational diabetes (6% of pregnancies). In a meta-analysis of 8 studies (18), a 55% reduction in the relative risk of developing gestational diabetes was noted in women who practice intense to high APS compared to a reference population. For Davenport (19), walking for 25 minutes, 3 or 4 times a week, for at least 6 weeks leads to a reduction in fasting and 1-hour postprandial blood sugar levels.

Also, exercise tends to decrease the number of patients requiring the introduction of insulin therapy, to delay the start of injections and even to decrease the number of insulin units needed.

The greatest benefit is reported for vigorous APS before pregnancy and continued during pregnancy, at least in a moderate way. Of course, physical exercise remains an adjuvant treatment for diabetes and will be associated with nutritional recommendations.

Barakat et al. (19) showed that regular practice of APS during the second and third trimesters of pregnancy does not increase the risk of maternal anemia.

In a study by Marquez-Sterling et al. (21) involving 15 women, those who had completed 1 hour of muscle strengthening with a coach in the gym reported unchanged sexual activity, while those who were less assiduous described a decrease in their sexual activity.

Weight less than 2,500 g is associated with risks of developmental delay and comorbidities.

The study by Orr et al. (22) presents identical birth weights between a group of athletes and a control group while a meta-analysis including 30 studies reports smaller and less fat babies (from -200 to -400 g) in women practicing APS, with a weight loss at the expense of fat mass (23). This effect is all the more important if APS is performed more than three times per week in the third trimester.

In another study, it was found that walking for 50 minutes per day in early pregnancy protected against low birth weight (24). Again, standing for more than 2.5 hours per day in the second trimester increased the risk of low birth weight by 3.23 (24).

" Physical exercise seems to improve fetal brain development ," reports Élise Labonté-LeMoyne, a researcher at the University of Montreal, at the annual meeting of Neurosciences in San Diego in November 2013. A comparative study on auditory memory, conducted on newborns whose mothers had been monitored during their pregnancy as active or sedentary, made it possible to deduce that the brains of babies whose mothers exercised develop more quickly than those of others.

All these studies show that there is a real benefit for the fetus and for the mother to the practice of APS during pregnancy. These results are most often the consequence of adapted and controlled sports training programs. Also, let us take advantage of the prosperous era of coaching and the prescription of APS to adapt our practices in order to limit the risks linked to pregnancy.