Pregnancy involves many anatomical and physiological changes that impact exercise. Regular moderate exercise is recommended for pregnant women and provides benefits like reducing gestational diabetes and preeclampsia. An individualized exercise program should account for changes across trimesters and avoid high-risk activities. Aerobic exercise, water workouts, and weight lifting with light weights are generally suitable if intensity remains moderate.

1. Pregnancy and Exercise

2. Anatomical Changes: Uterus
• Expanding uterus
• Elevated center of gravity
• Progressive lumbar lordosis
• Theoretical increased risk of fall
• 40 to 50% report lower back pain

3. Anatomical Changes: Weight
• Increased total body weight
• 25 lbs/11Kg average weight gain
• Causes 5 x the weight on joints
• Soft tissue edema(swelling) occurs in >80%

4. Anatomical changes:
Ligament Laxity
 Increases as pregnancy progresses
 Due to increase in Relaxin hormone
 Widening of symphysis pubis
 Peripheral joint laxity

5. Pregnancy Physiology:
Cardiovascular
• BloodVolume increases up to 50%
• Sodium/total water retention
• Heart Rate increases ~20%
• Stroke volume increases

6. Pregnancy physiology with
exercise
• Heart rate – normal response
• Max HR no longer guide to monitoring intensity during
pregnancy
• Currently recommended to use
perceived exertion
• Borg scale 6 - 20
• Modified Borg scale 1-10

7. Pregnancy physiology with
exercise
•No adverse effects on uterine blood flow
due to redistribution to exercising
muscles
•FHR (fetal heart rate )usually up 10 to 30
beats in response to maternal exercise.

8. Pregnancy Physiology:
Respiratory Physiology
• Increased oxygen consumption (apporx 20%)
• Increased minute ventilation (Breathing rate)
• No Change FEV1
(Forced ExpiratoryVolume in One Second)

9. Pregnancy physiology:
Thermoregulatory
• Increased basal metabolic rate (Calories needed at rest)
• Increased heat production
• Better heat dissipation in pregnancy
• Increased risk of dehydration

10. Pregnancy Physiology:
Thermoregulation with exercise
• Trainers goal is to keep the client cool while
trying to maintain appropriate exercise
intensity.

11. Pregnancy outcomes that can be
improved by exercise
• Gestation Diabetes
• Preeclampsia
• Weight gain
• Improved mental health
• Overall decreased
subjective discomforts

12. Delivery outcomes improved
• Decreased time of active labor
• Decreased interventions
• forceps, c-section etc
• Increased fetal tolerance of delivery

13. Gestation Diabetes
• Studies show exercise can decrease gestational
diabetes

14. Preeclampsia
A condition in pregnancy characterized by high
blood pressure and sometimes with fluid retention
• Risk decreases more with increasing time spent exercising.
• (GP clearance needed to partake in exercise)

15. Debunking the risks of
aerobic exercise
No increased risk of:
• Miscarriage
• Congenital malformations
• Ectopic
• Pre-term labor
• Unexplained fetal deaths

16. Contraindications for Exercise
& Pregnancy
Absolute (Do not exercise)
• Significant cardiac disease
• Restrictive lung disease
• Placental abruption
placenta separates early from the
uterus
• Premature labor
• Rupture of membranes
• preeclampsia
Relative (GP sign off required)
• anemia
• Bronchitis
• Diabetes
• Extreme obesity or low BMI
• Multiple gestation
• Sedentary lifestyle
• Fetal growth restriction
• smoking

17. ACOG Guidelines
The American College of Obstetricians and Gynaecologists
• “In the absence of contraindications, pregnant women
should be encouraged to engage in regular, moderate
intensity physical activity to continue to derive health
benefits during their pregnancies as they did prior to
pregnancy”
• 30 minutes or more of moderate exercise per day
recommended
• Avoid the supine position during exercise as much as
possible
• Recommend against scuba diving during pregnancy, sports
at risk for abdominal trauma

18. ACOG Guidelines cont.
• Exercise may benefit women with gestational diabetes
• Competitive athletes may require close obstetric
supervision
• Moderate exercise during postpartum does not
negatively impact nursing and neonatal weight gain
• Return to physical activity after pregnancy
reduces the risk of postpartum depression

19. Exercise prescription
• Very similar to non-pregnant individuals
• Sedentary women can safely begin exercising during
pregnancy but monitor closely.
• Need to be flexible – adapt as pregnancy progresses
• Active women may be advised to restrain from very
strenuous activities and competition
• Pre-exercise medical screening essential

20. Water Exercise
• Lower forces across weight bearing joints
• Body heat readily dissipated
• Balance and falling not an issue

21. Weight Lifting During Pregnancy
• Multiple repetitions (12 reps +)
• Avoid heavy or isometric
• No increased risk of injury
• Core strength = less lower back pain
• Better tolerate weight gain

22. Exercise Position
• Avoid supine position after 1st trimester and prone
position at all times (where abdominal contact is made).
• Standing position exercise kept to a minimum

23. ExercisesTo Avoid
• Contact sports
• Soccer, Rugby, Hockey, Basketball etc
• Risk of trauma
• Tennis, Skiing, Outdoor Cycling, Gymnastics etc
• Scuba diving
• Decompression problems fetus
• Altitude
• Decreased oxygen

24. Intensity
• Moderate intensity as with non-pregnant
• Use RPE/Modified Borg Scale 1-10 (6-8 for Cardio Exercise)
• No longer use % of MHR

25. Duration
• At least 150 min/week of moderate intensity
• Careful attention to hydration, heat and caloric intake
in exercise > 45 minutes in pregnancy

26. Nutritional Recommendations
• Approximately 300-500kcal/day more
• Increased risk of hypoglycemia(Low Blood sugar)
• Increased carbohydrate need

27. Warning SignsToTerminate
Exercise
• Vaginal bleeding
• Difficult or laboured
breathing prior to
exertion
• Dizziness
• Headache
• Chest pain
• Muscle weakness
• Signs of
thrombophlebitis
(inflammation of the wall of a vein
with associated thrombosis, often
occurring in the legs during
pregnancy)
• Uterine contractions
• Decreased fetal
movement
• Leakage of fluid

28. Postpartum
• Safe to resume training within 8 -12 weeks of natural
delivery.
• Faster regain of abdominal muscles
• Improved bladder control
• Care with return to high impact activities such as running
• Decreased post partum depression
• Increased weight loss
• GP sign off for return after c-section or delivery that had
complications

29. Postpartum Breastfeeding
Overall no decrease in ability to breastfeed when
exercising after childbirth

30. Summary
• Many anatomical and physiological changes during
pregnancy
• Pregnant women should be encouraged to exercise
regularly
• Flexible and individual exercise prescription
• Avoid contraindicated exercises and conditions
• Heat, altitude, impact sports etc
• Continue exercising postpartum