EXERCISE IN PREG-NANCY

MF FELLOWKIM MIJUNG

INTRODUCTION• Physical activity and Exercise

• maintains and improves cardiorespiratory fitnes

• reduces the risk of obesity and associated comorbiditie

• greater longevity

• Physical inactivity is the fourth-leading risk factor for early mortality worldwide

• Independent risk factors for maternal obesity and related pregnancy compli-cations, including GDM in pregnancy

INTRODUCTION• Concern!

• regular physical activity during pregnancy may cause miscarriage, poor fetal growth, mus-culoskeletal injury, or premature delivery.

• For uncomplicated pregnancies, these concerns have not been substantiated.

• maintain or improve fitness Obstet Gynecol. 2012

• prevent excessive gestational weight gain Cochrane Database Syst Rev. 2012

• prevent or reduce low back pain Int J Gynaecol Obstet. 2011

• reduce the risk of developing GDM and preeclampsia

• reduce having a cesarean delivery

ANATOMIC AND PHYSIOLOGIC AS-PECTS• Pregnancy Anatomic, physiologic changes➩• Increased weight gain • Shift in the point of gravity • results in progressive lordosis Increase in the forces across joints and the spine

• More than 60% experience low back pain • Strengthening of abdominal and back muscles

minimize risk

• Lower extremities edema and joint laxityThe most common sports-related injuries in pregnancy are musculoskeletal

PHYSIOLOGIC CHANGE DURING PREG-NANCY• Hemodynamic changes

• Blood volume, heart rate, stroke volume,

cardiac output ⇑• Systemic vascular resistance ⇓

• Respiratory changes • Minute ventilation up to 50% ⇑• Tidal volume ⇑• Pulmonary reserve ⇓• Physiologic respiratory alkalosis

Motionless postures (certain yoga positions, supine position) ⇒ decreased venous return, hypotension

should be avoided as much as possible ⇒

Short of breathAbility to exercise anaerobically ⇓O2 availability for strenuous aerobic exercise ⇓ (esp. obese women)

TEMPERATURE REGULATION

• Highly dependent on hydration and environmental condition

• During exercise, pregnant women should stay well-hydrated, wear loose-fitting clothing, and avoid high heat and humidity to protect against heat stress, par-ticularly during the first trimester

• Exposure to heat from sources like hot tubs, saunas, or fever has been associ-ated with an increased risk of neural tube defects.

• Exercise would not be expected to increase core body temperature into the range of concern.

Despite pregnancy is associated with profound anatomic and physiologic changes, Exercise has minimal risks and has been shown to benefit most women.

FETAL RESPONSE TO MATERNAL EX-ERCISE • Minimum-to-moderate increases in fetal heart rate by 10–30 beats per

minute over the baseline during or after exercise

• Three meta-analyses concluded : differences in birth weight were minimal to none in women who exercised during pregnancy compared with controls

• However, exercise vigorouse group during the third trimester were more likely to deliver infants weighing 200–400 g less, although there was not an in-creased risk of fetal growth restriction

Am J Obstet Gynecol. 1986

FETAL RESPONSE TO MATERNAL EX-ERCISE • UA blood flow, fetal heart rates, and ,

NST, biophysical profiles before and af -ter strenuous exercise in 2nd trimester

• The increase in rate may be accompa-nied by a reactive FHR pattern

(ie, FHR accelerations); postexercise re-activity is generally achieved

within 20 minutes. Biophysical profile scores were reassuring. Szymanski LM, Satin AJ., Obstet Gynecol

2012;119:603–10

30 minutes of strenuous exercise was well tolerated by women and fetuses

in active and inactive pregnant women

BENEFITS OF EXERCISE DURING PREGNANCY

• Women who exercise during pregnancy• Decreased GDM• Decreased cesarean and operative vaginal delivery • Decreased postpartum recovery time • Lower glucose levels in women with GDM • Help prevent preeclampsia Obstet Gynecol. 2015

Med Sci Sports Exerc. 2005

RISK FOR FETAL GROWTH RESTRICTION

• Modest decrease in overall weight gain (1–2 kg) in normal weight, over-weight, and obese women

• Low risk women (2015 systematic review of randomized trials ) : regular participation in a supervised prenatal exercise program resulted in a clinically insignificant reduction in birthweight compared with usual care and no increase in small for gestational age newborns

Obstet Gynecol. 2015

RECOMMENDING AN EXERCISE PROGRAM

MOTIVATIONAL COUNSELING

• Pregnancy is an ideal time for behavior modification, adopting a healthy lifestyle.

• Patients are more likely to control weight, increase physical activ-ity, and improve their diet if their physician recommends.

• Motivational counseling tools such as the Five A’s (Ask, Advise, Assess, Assist, and Arrange) approach.

Serdula MK et al., JAMA 2003;289:1747–50

PRESCRIBING AN INDIVIDUALIZED EXER-CISE PROGRAM A. A thorough clinical evaluation to ensure the patient does not have medical reasons to

avoid exercise.

Committee Opinion No. 650. American College of Obstetricians and Gynecologists. Obstet Gynecol 2015

B. Exercise program • Eventual goal of moderate-intensity exercise for at least 20–30

minutes per day on most or all days of the week

Committee Opinion No. 650. American College of Obstetricians and Gynecologists. Obstet Gynecol 2015

1) Physical activities

• Ratings of perceived exertion may be a more effective means to monitor exercise intensity during preg-nancy than heart-rate parameters

Borg GA. Psychophysical bases of perceived exertion. Med Sci Sports Exerc 1982

• For moderate-intensity exercise, ratings of perceived exertion 13–14 on the 6–20 Borg scale of perceived exertion

• “Talk test” As long as a woman can carry on a conversation while exercising, she is likely not overexerting herself

2) Exercise Intensity

• Women should be well hydrated, avoid long periods of lying flat on their backs, and stop exercising if they have any of the warning signs

C. Environmental Control

• High-intensity or prolonged exercise in excess of 45 minutes can lead to hypoglycemia; • Adequate caloric intake before exercise, or

limiting the exercise session

• Prolonged exercise : in a thermoneutral environment or in controlled environmental conditions (air conditioning) with proper hydration

• Core body temperatures rose less than 1.5°C and stayed within safe limits

SPECIAL POPULATIONS • Pregnant women who were sedentary before pregnancy

• more gradual progression of exercise

• ACOG guideline : “bed rest is not effective for the prevention of preterm birth and should not be routinely recommended” • at risk of venous thromboembolism, bone demineralization, and deconditioning.

• Obese women should start with low-intensity, short periods of exercise and gradu-ally increase as able. • modest reductions in weight gain and no adverse outcomes

• Competitive athletes frequent and closer supervision • particular attention to avoiding hyperthermia and prevent weight loss

EXERCISE IN THE POSTPARTUM PE-RIOD

Resuming exercise activities • Incorporating new exercise routines after delivery is important in supporting life-

long healthy habits. • Exercise and a healthy diet postpartum promote weight loss• Participation in exercise programs diminishes after childbirth

• frequently leading to overweight and obesity

• In the absence of medical or surgical complications, rapid resumption • Pelvic floor exercises could be initiated in the immediate postpartum period.

EXERCISE IN THE POSTPARTUM PE-RIOD Nursing women should consider …• Regular aerobic exercise

• improve maternal cardiovascular fitness without affecting milk production, com-position, or infant growth

• Ensure adequate hydration before commencing physical activity• Feeding their infants before exercising• Brest engorgement• Increased acidity of milk secondary to any build-up of lactic acid.

SUMMARY• Despite, pregnancy is associated with profound anatomic and physiologic changes,

exercise has minimal risks and has been shown to benefit most women. • Women with uncomplicated pregnancies should be encouraged to engage in physical

activities before, during, and after pregnancy. • Obstetrician–gynecologists and other care providers should carefully evaluate women

with medical or obstetric complications before making recommendations on physical activity during pregnancy.

• Physical activity and exercise during pregnancy promotes physical fitness and may prevent excessive gestational weight gain. Exercise may reduce the risk of gestational diabetes, preeclampsia, and cesarean deliveries.

• Additional research is needed to further clarify effective behavioral counseling meth-ods and optimal type, frequency, and intensity of exercise.

Eventual goal of moderate-intensity exercise for at least 20–30 minutes per day on most or all days of the week

Thank you for your attention !!