Level 3 Award in Pre / Post Natal Exercise Programming Design

Aims of the session By the end of the session the learner should have an understanding of Physical activity and health considerations for the Pre Natal client

Learning Outcomes By then end of the session the learner should be able to Describe one physiological or biomechanical change associated with each trimester

Physiological changes associated to pregnancy When a woman enters pregnancy, physiological changes happen, they effect; Cardio-vascular system, Heart rate, Body Temperature & Sweating, Respiratory Function, Hormone response, Weight Gain, Muscle, ligament, joint & postural adaptations.

General changes associated to pregnancy https://www.youtube.com/watch?v=acw2yxjpDpw 3 mins 40secs

Physiological changes associated to pregnancy Cardio-respiratory changes In early stages of pregnancy, there is a release of hormones which relaxes blood vessels, as a result vessels become more elastic & expand Causing a fall in blood pressure & a decrease in the amount of blood moving in & out of the heart.

Physiological changes associated to pregnancy Cardio-vascular changes This shortfall in blood volume is referred to as “vascular underfill” with the following symptoms; Waves of sudden fatigue A racing pulse Nausea Pallor (change in colour) Sweating Dizziness, especially when getting up

Physiological changes associated to pregnancy Cardio-vascular changes - vascular By the 4th month these will subside due to increase in blood volume and pressure,

Physiological changes associated to pregnancy Cardio-respiratory changes - Respiration The increasing size of the uterus presses upwards into the diaphragm reducing the degree to which it can move down. So the rib cage elevates and widens to compensate.

Physiological changes associated to pregnancy Cardio-vascular changes – heart rate Early Pregnancy leads to a slightly elevated heart rate to compensate for low blood volume & pressure, Mid pregnancy vascular corrections means that HR will become similar to pre conception levels Late pregnancy, blood volume increases making it difficult to increase HR’s to high levels despite working hard.

Physiological changes associated to pregnancy Body Temperature During pregnancy a mothers ability to remove heat from her body must increased, reducing the risk of overheating for the baby, The set point for sweating reduces.

Physiological changes associated to pregnancy Body Temperature When a woman exercises at 65% MHR in late pregnancy, Her peak core temperature is relatively low, Due to her sweating point being lower, Therefore vigorous exercise could be considered a risk due to dehydration.

Physiological changes associated to pregnancy Body Temperature considerations Having adequate hydration, Wearing lightweight clothing, Avoid exercise in hot and humid conditions,

Physiological changes associated to pregnancy Hormones The main effects of relaxin is to soften various tissues in preparation for birth, including; Ligaments Cartilage The cervix

Physiological changes associated to pregnancy Hormones The effects are particularly strong around the sacroiliac joints and the pubic symphasis, Relaxin has a general effect also and will increase joint laxity all over the body.

Physiological changes associated to pregnancy Hormones Levels of insulin resistance increase as pregnancy progresses which can cause symptoms similar to a mild diabetes, glucose remains in the blood stream, In later half of pregnancy, the body can become insulin resistant.

Physiological changes associated to pregnancy Hormones Insulin resistance serves a valuable purpose. Increases dependency on fats as primary fuel source, Increases the glucose available in the mothers blood stream to support the rapid growth of the foetus.

Physiological changes associated to pregnancy Hormones To support glucose availability during exercise, it is advisable to increase food intake, 150 calories per day in 2nd trimester, and up to 300 calories per day in 3rd trimester.