The Sunday News
Simon Gama
Research supports the prescription of exercise during pregnancy as an effective tool for improving good emotional well-being, maintaining optimum management and controlling blood glucose level.
The Par-Med X is a validated screening tool for readiness for physical activity and screen for contradictions while providing current exercise education. The guidelines for exercise prescription during pregnancy refer to low-risk, pregnancy and these are detailed below, after discussion on possible risks of exercising while pregnant.
Potential risks of maternal exercise to the foetus
The potential risks of maternal exercise to the foetus include: Foetal injury, foetal distress, intrauterine growth retardation, prematurity, foetal malformations.
Direct trauma to the foetus is rare but may occur at second and third trimester. For this reason, contact sport with a high risk of collision should be average after the first trimester.
Changes in foetal heart rate may occur in response to exercise although this seems to be related to gestational age and the duration, intensity and type of exercise. Changes in foetal heart rate may be due to relative hypoxic effect on the foetus. Generally increases in foetal heart rate of between 10 and 30 beats per minute are found following maternal exercise. Occasional, bradycardia (slowing of the heart rate) is observed. The clinical significance of foetal tachycardia or bradycardia is uncertain.
The average birth weight of babies whose mother have exercised intensively and very frequently during pregnancy is lower than that of babies to sedentary mothers. They do not appear to be any short or long term adverse sequel as a result of this difference in weight between groups. There is a theoretical risk of premature labour associated with maternal exercise due to increased levels of noradrenaline in (norepinephrine), which may cause increased uterine irritability and subsequent premature labour. This has not been observed in practice.
The other major area of concern for the health of the foetus with maternal exercise is the risk of hyper anaemia. Animal data suggest that a core temperature in excess of 39 degrees Celsius (102 Fahrenheit) may result in neural tube defects in the foetus. This malformation is the result of failure of closure of the neural tube a process that occurs approximately twenty five days after conception. This has not been confirmed in humans. Pregnant women, however, should avoid hyperthermia during the first weeks of their pregnancy. Moderate exercise in normal environmental conditions result in minimal increase in core temperature.
Risks to the mother: The pregnant woman shows an increase susceptibility in muscular skeletal injuries, especially the development in pain in the low back, sacroiliac region or pubic symphysis. The mechanism of the development of low back and pelvic girdle pain in pregnant woman probably relates to a combination of factors, including change in the centre of gravity upwards and forward associated with forward tilting of the pelvis, an increase lumbar lordosis and loosening of ligaments associated with increased levels of the hormone relaxing.
The incidence of low back pain can be reduced by careful attention to posture and avoidance of sudden movements, as well as strengthening of the abdominal and back muscles. Pelvic girdle pain can be reduced by advice on posture, use of a sacroiliac belt, stabilising exercises and acupuncture. Another possible problem affecting the pregnant woman is hypotension. Postural hypotension results from prolonged standing whereby there is a decrease in cardiac output due to slowed venous return. Supine hypotension can occur with lying or exercising in the supine position. In the supine position, the uterus compresses the major blood vessels, resulting in reduced blood return to the heart and hypotension.
Advantages of exercise during pregnancy
The advantages of exercise during pregnancy relate more to the general physical and psychological well-being of the mother rather than to any effects on the pregnancy itself.
Women who exercise prior to pregnancy and continue to do so in pregnancy weigh less, gain less weight and deliver slightly smaller babies than sedentary women. Increased fitness may enable women to cope better with labour. There is no evidence that women who have exercised during pregnancy have a shorter or easier labour. Even overweight pregnant women who commence an aerobic exercise programmes can reap beneficial effects on fitness levels throughout pregnancy.
Exercise during pregnancy is also valuable for the prevention and treatment of illnesses such as gestational diabetes. Even though data is sparse, it appears that women who engage in recreational physical activity during pregnancy have an approximately 50% reduction in the risk of gestational diabetes compared to inactive women. Active women also have an approximately 40% reduction in risk of pre-eclampsia.
The writer, Simon Gama is a fitness trainer at Body Works Gym in Bulawayo.
