In This Chapter

Benefits and Risks of Exercise During Pregnancy Maternal Fitness Gestational Diabetes Preeclampsia Maternal Obesity Maternal Exercise and the Fetal Response Contraindications and Risk Factors Physiological Changes During Pregnancy Musculoskeletal System Cardiovascular System Respiratory System Thermoregulatory System Programming Guidelines and Considerations for Prenatal Exercise Biomechanical Considerations for the Pregnant Mother Low-back and Posterior Pelvic Pain Pubic Pain Carpal Tunnel Syndrome Diastasis Recti About The Author Stress Urinary Incontinence Sabrena Merrill, M.S., has been actively involved in the fitness Nutritional Considerations industry since 1987. An ACE-certified Group Fitness Instructor Psychological Considerations and Personal Trainer, Merrill teaches group exercise, owns and Benefits and Risks of Exercise Following Pregnancy operates her own personal training business, has managed Physiological Changes Following fitness departments in commercial facilities, and lectured to Pregnancy university students and established fitness professionals. She Programming Guidelines and Considerations for Postnatal has a bachelor’s degree in exercise science as well as a master’s Exercise degree in physical education from the University of Kansas, and Biomechanical Considerations for the Lactating Mother has numerous certifications in exercise instruction. Merrill acts Case Study as a spokesperson for the American Council on Exercise (ACE) Summary and is involved in curriculum development for ACE continuing education programs. Additionally, Merrill presents lectures and workshops to fitness professionals nationwide. Chapter 23

Pre- and Postnatal Exercise Sabrena Merrill

n increasing amount of research on exercise in pregnancy has led to a waning debate over the maternal and fetal risks of regular physical activity during pregnancy. There is a growing trend of women entering pregnancy with regu- Alar aerobic and strength-conditioning activities as a part of their daily routines. Many women who are not physically active view pregnancy as a time to modify their lifestyles to include more health-conscious activities, including exercise. Traditionally, the medical community has encouraged pregnancy (Zhang & Savits, 1996; Ning et al., 2003). Given pregnant women to reduce their habitual levels of physical the current epidemic of obesity and its associated comorbidi- exertion and refrain from starting strenuous exercise pro- ties, as well as the apparent health risks of not exercising, grams. These restrictive guidelines were based on concerns fitness professionals who are competent to work with this that exercise could negatively affect pregnancy outcomes population can provide safe and effective exercise program- by increasing core body temperature, raising the risk of ming to promote a healthy pregnancy and healthy lifestyle congenital anomalies, and shifting oxygenated blood and after the birth. nutrients to maternal skeletal muscles—and away from the fetus [American College of Obstetricians and Gynecologists Benefits and Risks of Exercise (ACOG), 1985; Shangold, 1989]. More recent investiga- During Pregnancy tions, however, focusing on both aerobic training and strength conditioning in pregnancy, have shown no increase in early vidence is increasing that regular prenatal exercise pregnancy loss, late pregnancy complications, abnormal fetal is an important component of a healthy pregnancy. growth, or adverse neonatal outcomes, suggesting that previ- EExpectant mothers can maintain or even improve ous recommendations have been overly conservative (Clapp, cardiovascular and muscular fitness. Additionally, regular 1989; Klebanoff et al., 1990; Hatch et al., 1993; Kardel et al., 1998; Sternfeld et al., 1995; O’Neill, 1996). exercise is associated with a lower incidence of excessive While prenatal exercise recommendations from allied maternal weight gain, gestational diabetes mellitus (GDM), healthcare professionals are becoming more commonplace, pregnancy-induced hypertension, varicose veins, deep vein the majority of women do not get the recommended mini- thrombosis, dyspnea, and low-back pain (Davies et al., 2003; mum amount of daily physical activity. It is estimated that Weissgerber et al., 2006). Furthermore, it has been shown only 42% of pregnant women exercise 30 minutes or more that women who continue regular, weightbearing exercise at least three times a week, and 23% of healthy, previously throughout the entire duration of pregnancy tend to have active women stop exercise or reduce it significantly during easier, shorter, and less complicated deliveries (Clapp, 2002). 576 Chapter twenty-three Pre- and Postnatal Exercise

Maternal Fitness considered an adjunct therapy for women with Healthy women who consistently exercise GDM. Preliminary studies have found that women throughout pregnancy show a marked reduction who participated in any type of recreational activ- in weight gain, fat accumulation, and fat reten- ity within the first 20 weeks of gestation decreased tion. In one study, pregnant exercisers had average their risk of GDM by almost half (Dempsey et al., increases in weight (29 pounds; 13 kg) and skin- 2004). Research has shown that even mild exercise • fold thicknesses (10 mm) well within the normal (30% of V O2max, regardless of modality) com- range, but their body-fat mass averaged 3% lower bined with nutritional control can help prevent than the control subjects who performed no exer- GDM and excessive weight gain during pregnancy cise during pregnancy (Clapp & Little, 1995). In (Batada et al., 2003). other words, the women who performed regular weightbearing exercise throughout their pregnan- Preeclampsia cies maintained a leaner body composition than A serious maternal-fetal disease called pre- their sedentary counterparts. eclampsia is diagnosed after 20 weeks of gestation Due to the many physiological adaptations that and characterized by persistent hypertension occur during pregnancy, women who continue (>140/90 mm/Hg) and proteinuria (24-hour moderate-to-high levels of endurance exercise can urinary protein level ≥0.3 g) (ACOG, 2002a). experience an increase in their maximal aerobic Complications associated with preeclampsia capacity by up to 10% postpartum, even though include preterm birth, abruptio placentae, renal exercise volume is typically reduced by the added failure, pulmonary edema, cerebral hemorrhage, responsibility of childcare (Clapp & Capeless, circulatory collapse, eclampsia, and the necessity 1991). Furthermore, improvements in aerobic for immediate delivery regardless of gestational • efficiency, but not necessarily V O2max, are seen in age. Risk factors for preeclampsia include abnor- women who begin a low-volume exercise program mal placental development, predisposing maternal (moderate intensity for 20 minutes, three to five constitutional factors, oxidative stress, immune days per week) during pregnancy (Clapp, 2002). maladaptation, and genetic susceptibility. A review of the literature examining physi- Gestational Diabetes cal activity and preeclampsia risk reveals several Glucose intolerance that is first recognized or epidemiological studies that indicate that regular diagnosed during pregnancy is called gestational leisure-time physical activity in early pregnancy diabetes. Maternal muscular insulin resistance is associated with a reduced incidence of pre- during mid-pregnancy is a normal response to hor- eclampsia (Weissgerber et al., 2004). Although monal adaptations that occur to ensure adequate not proven, several protective mechanisms associ- glucose regulation for fetal growth and develop- ated with exercise are thought to play a role in ment. In women with GDM, this insulin increase is preeclampsia prevention, including enhanced exacerbated, resulting in maternal hyperglycemia. placental growth and vascularity, enhanced anti- Women with GDM are more likely to have com- oxidant defense systems, reduction of the systemic plications such as a difficult labor and delivery, as inflammatory response, and improved endothelial well as delivery by Caesarean section (C-section). function (Weissgerber et al., 2006). Risk factors for GDM include a family history Traditional treatment of gestational hyperten- of diabetes, previous diagnosis of GDM, belonging sion and mild preeclampsia has focused on bed to a high-risk ethnic group (Aboriginal, Hispanic, rest to prevent blood pressure increases associated South Asian, Asian, or African descent), age ≥35 with daily activity. However, up to one-third of years, overweight [body mass index (BMI) ≥25], women fail to comply with bed rest recommenda- obesity (BMI ≥30), or a history of insulin resistance tions, and compliance does not affect pregnancy (ACOG, 2001). Once diagnosed, GDM patients outcome in women who develop mild preeclamp- are primarily treated through nutritional manage- sia in the latter part of gestation (Magee, Ornstein, ment by a registered dietician (R.D.). Exercise is & von Dadelszen, 1999). More recent treatment

ACE Advanced Health & Fitness Specialist Manual Pre- and Postnatal Exercise Chapter twenty-three 577577 guidelines for hypertension and mild preeclampsia delivery. Exercise performed before conception have shifted toward ambulatory management and during pregnancy may help to prevent these with careful patient monitoring (Lenfant, 2001; obesity-related complications by decreasing Moutquin et al., 1997). Exercise intervention BMI to a healthy range, preventing GDM and studies in women with gestational hypertension preeclampsia, and reducing the likelihood of and preeclampsia are inconclusive, and it remains excessive gestational weight gain. Prenatal exercise unclear whether a program of regular exercise also has been associated with a timely return to can positively affect this population. Exercise in pre-pregnancy weight after delivery (Rooney & women with high-risk pregnancy conditions, such Schauberger, 2002). as preeclampsia, should be closely monitored and supervised by their physicians in a clinical setting, Maternal Exercise and as these situations are outside the scope of prac- the Fetal Response tice for an ACE-certified Advanced Health & In uncomplicated pregnancies, fetal injuries are Fitness Specialist (ACE-AHFS). highly unlikely, as most of the potential fetal risks are hypothetical. However, there are several areas Maternal Obesity of theoretical concern surrounding maternal exer- In the U.S., the percentage of women of child- cise and its effects on the fetus. First, the selective bearing age (20 to 39 years) who are overweight redistribution of blood flow away from the fetus has climbed to 49% among white women and during regular or prolonged exercise in pregnancy 70% among African-American women (Okosun may interfere with the transplacental transport of et al., 2004). Obesity-related reproductive com- oxygen, carbon dioxide, and nutrients. To address plications that occur before, during, and after this concern, many experts recommend aquatic pregnancy may be reduced through lifestyle inter- exercise as an excellent choice of aerobic training ventions such as regular aerobic exercise. during pregnancy. During immersion, women Ovulatory infertility increases progressively with experience a smaller decrease in plasma volume as increasing BMI, as do the risks for polycystic ovar- compared to exercising on land. In addition, as a ian syndrome and menstrual irregularities. The result of the hydrostatic pressure in aquatic exer- effectiveness of regular aerobic exercise (three hours cise, maintenance of blood flow around the central per week) and educational seminars (one hour per organs may provide better maintenance of uterine week on weight-related topics) on restoring fertility and placental blood flow (Watson et al., 1991). in obese women was demonstrated by a six-month A second concern is that during exercise, tran- lifestyle intervention study (Clark et al., 1998). The sient hypoxia could result in fetal tachycardia subjects who completed the intervention lost an and an increase in fetal blood pressure. These average of 10.2 4.3 kg (22.4 9.5 lb). Prior to the fetal responses are protective mechanisms that study, all subjects had been infertile for at least two occur during obstetric events and allow the fetus years; however, 77% of the subjects conceived suc- to facilitate the transfer of oxygen and decrease cessfully during or after the lifestyle intervention. the carbon dioxide tension across the placenta. The authors hypothesized that improved fertility However, there are no reports to link such adverse resulted from the beneficial effects of reduced insu- events with maternal exercise. A majority of lin resistance and lower insulin concentrations on studies examining fetal responses to exercise moni- reproductive hormone profiles. tored fetal heart rate as an indicator of fetal stress During pregnancy, the risk of maternal and fetal (Collings, Curet, & Mullin, 1983; Clapp, 1985; complications increases with the degree of obesity. Artal, 1990; Carpenter et al., 1988; Wolfe et al., The incidence of preeclampsia and GDM increase 1988). Most of these studies show a minimum progressively in overweight and obese women. or moderate increase in fetal heart rate by 10 to Additionally, overweight and obese women are 30 beats per minute over baseline during or after more likely to deliver large-for-gestational-age maternal exercise. Fetal heart rate decelerations infants and require C-section and instrumental and bradycardia, with a frequency of 8.9%, have

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also been reported to occur during maternal 2003). However, it is recommended that women exercise. The causes of the alterations in fetal with complicated pregnancies be discouraged heart rate during maternal exercise are still from participating in exercise activities for fear of unclear, and no associated lasting effects on the impacting the underlying disorder or maternal or fetus have been reported. fetal outcomes. A third concern is intrauterine growth restric- ACOG has established that there are some tion due to strenuous physical activity. Studies women for whom exercise during pregnancy is on the effect of exercise during pregnancy absolutely contraindicated (Table 23-1), while and resultant birth weights are inconclusive. for other women the potential benefits of exer- Epidemiological studies have shown a link cising may outweigh the risks (Table 23-2). between strenuous physical activity, poor diet, Furthermore, fitness professionals and preg- and low birth weight. It has also been reported nant exercisers should familiarize themselves that mothers who perform strenuous physical with specific signs or symptoms that may indi- work in their occupations, such as repetitive lift- cate a problem, including those items listed in ing, have a tendency to deliver earlier and have Tables 23-3 and 23-4. It is imperative that an small-for-gestational-age infants (Naeye & Peters, ACE-AHFS perform routine health screenings 1982; Launer et al., 1990; McDonald et al., 1988). on all clients and require a physician’s clearance However, other studies have provided conflicting before initiating an exercise program with a data suggesting that other variables, such as inef- pregnant or postpartum woman. ficient nutrition, have to be present for strenuous In general, participation in a wide range of rec- activities to affect fetal growth (Saurel-Cubizolles reational activities appears safe during and after & Kaminski, 1987; Ahlborg Bodin, & Hogstedt, pregnancy. Overly vigorous activity in the third 1990). Overall, it appears that birth weight is not trimester, activities that have a high potential for affected by exercise in women who have adequate contact, and activities with a high risk of falling energy intake. should be avoided (Table 23-5). Additionally, women should refrain from activities with a Contraindications and Risk Factors risk of abdominal trauma, exertion at altitude Research from the past several decades has greater than 6000 feet (1829 m), and scuba diving produced valid and reliable evidence that supports (ACOG, 2002b). participation in a regular exercise program during Table 23-1 pregnancy because of the important maternal- Absolute Contraindications to fetal benefits it provides. In fact, the available Aerobic Exercise During Pregnancy studies show that adverse pregnancy or neonatal outcomes are not increased for exercising women • Hemodynamically significant heart disease (Clapp, 1989; Hall & Kaufmann, 1987; Hatch et • Restrictive lung disease • Incompetent cervix/cerclage al., 1993; Klebanoff et al., 1990; Kulpa, White, & • Multiple gestation at risk for premature labor Visscher, 1987). ACOG, the American College • Persistent second- or third-trimester of Sports Medicine (ACSM), the Canadian bleeding Society for Exercise Physiology (CSEP), and the • Placenta previa after 26 weeks of gestation Society of Obstetricians and Gynaecologists of • Premature labor during the current Canada (SOGC) all provided guidelines and pregnancy recommendations for exercise during pregnancy • Ruptured membranes • Preeclampsia/pregnancy-induced and the postpartum period that indicate that, hypertension in uncomplicated pregnancies, women with or without a previously sedentary lifestyle should be Source: American College of Obstetricians and encouraged to participate in aerobic and strength- Gynecologists (2002). Exercise during pregnancy and the postpartum period. ACOG Committee Opinion No. 267. conditioning exercises as part of a healthy lifestyle Obstetrics and Gynecology, 99, 171–173. (ACSM, 2010; ACOG, 2002b; SOGC & CSEP,

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Table 23-2 Table 23-4 Relative Contraindications to Warning Signs to Cease Aerobic Exercise During Pregnancy Exercise While Pregnant

• Vaginal bleeding • Severe anemia • Dyspnea prior to exertion • Unevaluated maternal cardiac arrhythmia • Dizziness • Chronic bronchitis • Headache • Chest pain • Poorly controlled type 1 diabetes • Muscle weakness • Extreme morbid obesity • Calf pain or swelling (need to rule out • Extreme underweight (BMI <12) thrombophlebitis) • History of extremely sedentary lifestyle • Preterm labor • Decreased fetal movement • Intrauterine growth restriction in current • Amniotic fluid leakage pregnancy • Poorly controlled hypertension Source: American College of Obstetricians and Gynecologists (2002). Exercise during pregnancy and the • Orthopedic limitations postpartum period. ACOG Committee Opinion No. 267. • Poorly controlled seizure disorder Obstetrics and Gynecology, 99, 171–173. • Poorly controlled hyperthyroidism • Heavy smoker Table 23-5 High-risk Exercises

Source: American College of Obstetricians and Gynecologists (2002). Exercise during pregnancy and the • Snow- and waterskiing postpartum period. ACOG Committee Opinion No. 267. • Rock climbing Obstetrics and Gynecology, 99, 171–173. • Snowboarding • Diving • Scuba diving • Bungee jumping Table 23-3 Reasons to Discontinue • Horseback riding Exercise and Seek Medical Advice • Ice skating/hockey • Road or mountain cycling • Any sign of bloody discharge from the vagina • Vigorous exercise at altitude (non-acclimated women) • Any “gush” of fluid from the vagina (premature rupture of membranes) Note: Risk of activities requiring balance is relative to • Sudden swelling of the ankles, hands, or face maternal weight gain and morphologic changes; some activities may be acceptable early in pregnancy but risky (possible preeclampsia) later on. • Persistent, severe headaches and/or visual disturbances (possible hypertension) Physiological Changes • Unexplained spell of faintness or dizziness During Pregnancy • Swelling, pain, and redness in the calf of one leg (possible phlebitis) uring pregnancy, a woman’s endocrine • Excessive fatigue, palpitations, or chest pain system signals changes in virtually every • Persistent contractions (more than six to Dpart of her body to prepare her and the eight per hour) that may suggest onset of fetus for gestation, delivery, and lactation. This premature labor section covers the adaptations related to exercise performance. Understanding these factors and Source: American College of Sports Medicine (2010). ACSM’s Guidelines for Exercise Testing and Prescription how they impact a woman’s ability to engage in (8th ed.). Philadelphia: Wolters Kluwer/Lippincott Williams prenatal physical activity is essential for safe and & Wilkins. effective exercise programming.

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Musculoskeletal System nausea, fatigue, cravings, constipation, bloating, With the average weight gain during preg- and frequent urination), these hormonal changes nancy in the range of 25 to 40 pounds (11 to result in an increase in the elasticity and volume 18 kg) (15 to 25% of pre-pregnancy weight), of the entire circulatory system (i.e., a decrease in forces across joints are significantly increased. systemic vascular resistance). Initially, this creates Such large forces may cause discomfort to a vascular “underfill” problem where the amount normal joints and increase damage to arthritic of blood returning to the heart decreases. To or previously unstable joints. A woman’s enlarg- correct the underfill, the body triggers the release ing abdomen increases the mechanical stress of several hormones, which cause a decrease in on the joints of the back, pelvis, hips, and legs the excretion of salt and water by the kidneys. as her center of gravity moves upward and out. Ultimately, the retained extra salt and water Because of these anatomical changes, pregnant expand plasma volume, allowing more venous women report a high incidence of low-back pain return to the heart, thereby increasing cardiac (up to 76%). (Brynhildsen, 1998; Kristiansson, output and improving arterial pressure and Svardsudd, & von Schoultz, 1996). blood flow to the organs. Eventually, hormonal During the first trimester, increased amounts signals cause increases in heart volumes (cham- of the hormones relaxin and progesterone are ber volume and stroke volume), blood volume, released to expand the uterine cavity. These hor- heart rate, and cardiac output. mones allow expansion by softening the ligaments By mid-pregnancy, cardiac outputs are 30 to 50% surrounding the joints of the pelvis (hips and lum- greater than before pregnancy (Morton, 1991). bosacral spine), thereby increasing mobility and Additionally, maternal stroke volume increases joint laxity. Whether or not joint laxity occurs in by 10% by the end of the first trimester, and is other joints, such as the neck, shoulder, or periph- followed by a 20% increase in heart rate during ery, is unclear. Theoretically, increased mechanical the second and third trimesters (Pivaranik, 1996; stress combined with joint laxity would predispose Morton et al., 1985). Maternal resting heart rate pregnant women to increased incidence of strains can be up to 15 beats per minute higher than pre- and sprains. However, with the exception of the pregnancy rates near the third trimester. Mean reporting of low-back pain, data on the effects arterial pressure decreases 5 to 10 mmHg by the of increased weight of pregnancy on joint injury middle of the second trimester before gradually and pathology are lacking. While an increased increasing back to pre-pregnancy levels. These incidence of falling during pregnancy has not been hemodynamic changes appear to establish a circu- reported, a woman’s balance may be affected by latory reserve necessary to provide nutrients and changes in posture, predisposing her to loss of bal- oxygen to both mother and fetus at rest and during ance and increased risk of falling. Despite a lack moderate exercise. Since heart-rate response among of clear evidence that musculoskeletal injuries are pregnant exercisers is variable, ratings of perceived increased during pregnancy, these possibilities exertion (RPE) should be used to assess intensity should be considered when designing prenatal instead of traditional heart rate–based methods. exercise programs. As pregnancy progresses, a woman’s body posi- tion can affect her cardiovascular system both at Cardiovascular System rest and during exercise. After the first trimester, During pregnancy, the entire cardiovascular the supine position results in relative obstruction system experiences dramatic changes as hor- of venous return, and therefore decreased cardiac monal signals initiate relaxation and reduced output. For this reason, supine positions should responsiveness in most, if not all, of the smooth be avoided as much as possible during rest and muscle cells in a woman’s blood vessels. In addi- exercise. In addition, motionless standing is associ- tion to causing many of the unpleasant early ated with a significant decrease in cardiac output. symptoms of pregnancy (e.g., lightheadedness, Therefore, this position should be avoided.

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Respiratory System of 1.5° C during the first 30 minutes of exercise, The delivery of oxygen to the mother and and then reaches a plateau if exercise is continued fetus is enhanced through improvements in lung for an additional 30 minutes (Soultanakis, Artal, function during pregnancy. At rest, an increase & Wiswell, 1996). If heat production exceeds in the depth of each breath increases the amount heat dissipation capacity, as is commonly the of air inhaled by up to 50% or more (Prowse & case during exercise in hot, humid conditions or Gaensler, 1965; Artal et al., 1986). This increase is during very high-intensity exercise, a woman’s the result of elevated levels of progesterone, which core temperature will continue to rise. During stimulates “overbreathing” by increasing the prolonged exercise, loss of fluid as sweat may brain’s sensitivity to carbon dioxide. As a result, compromise heat dissipation. Given that fetal oxygen tension is increased and carbon dioxide body core temperatures are naturally about 1° C tension is decreased in the alveoli. Ultimately, higher than maternal temperatures, maintenance these directional changes in breathing gases widen of proper hydration, and therefore blood volume, the pressure gradients, which improve the effi- is critical to heat balance. Research examining ciency of oxygen uptake from the lungs and the the effects of exercise on core temperature during elimination of carbon dioxide from maternal and pregnancy is limited. The results of some human fetal blood and tissues. studies suggest that hyperthermia in excess of Prenatal adaptations of the respiratory system 39° C (100° F) during the first 45 to 60 days cause women to experience an associated increase of gestation may be teratogenic in humans in oxygen uptake and a 10 to 20% increase in base- (Milunsky et al., 1992; Edwards, 1986). However, line oxygen consumption (Pivarnik et al., 1992; there have been no reports that hyperthermia Sady et al., 1989). Peak ventilation and maximal associated with exercise causes malformations of aerobic capacity are maintained during pregnancy. the embryo or fetus in humans. As a result of this maintained function and the pregnancy-induced increase in alveolar ventila- Programming Guidelines tion, gas transfer at the tissue level may improve. This causes a “training effect” of pregnancy in and Considerations for women who maintain moderate-to-intense exer- Prenatal Exercise cise programs throughout gestation, and may explain anecdotal reports of women who experi- xercise programming guidelines for pre- ence an improvement in competitive endurance natal activity include the same elements performance after giving birth. Eas guidelines for non-pregnant women. Aerobic exercise consisting of any activity that Thermoregulatory System uses large muscle groups in a continuous rhythmic A woman’s ability to dissipate heat improves manner (e.g., walking, hiking, jogging/running, during pregnancy. The improved ability to elimi- aerobic dance, swimming, cycling, rowing, danc- nate body heat is most likely due to a decrease ing, and rope skipping) may be appropriate. Some of the body’s set point for normal temperature activities, such as scuba diving and prolonged exer- in early pregnancy and a significant increase in tion in the supine position, should be avoided due blood flow to the skin, which increases the rate to the potential for fetal hypoxia. Activities that of heat loss directly into the air. Additionally, increase the risk of falls, such as skiing, or those a 40 to 50% increase in tidal volume allows a that may result in excessive joint stress, such as pregnant woman to increase heat loss through jogging and tennis, should be engaged in only after exhalation by 40 to 50%. evaluation and consultation with a physician. During moderate-intensity aerobic exercise Musculoskeletal conditioning appears to be safe in thermoneutral conditions, the core tempera- and effective during pregnancy when low weights ture of non-pregnant women rises an average and multiple repetitions through a dynamic,

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controlled range of motion are performed. stating that the mode, frequency, duration, and While research is lacking, it would be prudent overload principles for cardiorespiratory, resis- to limit repetitive isometric or heavy-resistance tance, and flexibility exercise are the same for weightlifting, as well as any exercises that result pregnant women as for non-pregnant women. in a large pressor response (i.e., a dispropor- According to ACSM, pregnancy-specific issues tionate rise in heart rate during resistance to consider when designing prenatal exercise training resulting from autonomic nervous programs focus on attaining additional calories system reflex activity). Additionally, mainte- to maintain homeostasis, avoiding motionless nance of normal joint range of motion through standing, preventing maternal hyperthermia individualized stretching exercises is acceptable. and hypoglycemia, and avoiding high-risk However, pregnant exercisers should be aware exercises (Table 23-6). Furthermore, the sole of increased ligamentous laxity and strive to use of heart-rate monitoring to assess exercise limit excessive stretching or ballistic stretching intensity is not recommended for pregnant movements during pregnancy. exercisers due to the natural physiological Several national health and medical organiza- influences of the cardiovascular system during tions have published recommendations and pregnancy. The “category” RPE scale (6–20) guidelines on exercise and pregnancy (ACOG, or the “category-ratio” Borg scale (0–10) may 2002b; ACSM, 2010; SOCG & CSEP, 2003). be used. Ratings of “fairly light” to “somewhat Not surprisingly, the content in the guidelines hard” are the recommended intensity ranges for from the different organizations is similar. prenatal exercise (Pivernak et al., 1991; Clapp, Specifically, the ACOG Committee Opinion Lopez, & Harcar-Sevcik, 1999). on exercise during pregnancy published in 2002 Another set of guidelines, jointly sponsored recommends that, barring medical or obstetric by SOGC and CSEP, promote similar recom- contraindications, pregnant women engage mendations as those set forth by ACSM and in 30 or more minutes of moderate exercise ACOG, with the addition of a modified ver- on “most” days of the week (ACOG, 2002b). sion of the conventional age-corrected heart This recommendation is essentially the same rate target zone for pregnant exercisers (Table as that made for the general population by the 23-7), and a recommendation for resistance CDC and ACSM (ACSM, 2010). ACOG exercise and aerobic exercise (SOGC/CSEP, and ACSM jointly support recommendations 2003). Furthermore, the SOGC/CSEP

Table 23-6 Special Considerations for Prenatal Exercise Programming

• Pregnancy requires an additional 300 calories per day to maintain homeostasis. Therefore, women should ingest additional calories to meet the needs of exercise and pregnancy. • Heat dissipation is important throughout pregnancy. Appropriate clothing, environmental considerations, and adequate hydration should be priorities during the exercise program to prevent the possibility of hyperthermia and the corresponding risk to the fetus. Pregnant women should drink ample water to prevent dehydration and avoid brisk exercise in hot, humid weather or when suffering with a fever. • Pregnant women should avoid exercise that involves the risk of abdominal trauma, falls, and excessive joint stress. Sport activities such as softball, basketball, and racquet sports are not recommended because of the increased risk of abdominal injury. When exercising, pregnant women should be aware of the signs and symptoms for discontinuing exercise and seeking medical advice (see Table 23-3).

Source: American College of Sports Medicine (2010). ACSM’s Guidelines for Exercise Testing and Prescription (8th ed.). Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins.

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position statement provides a plan for inactive Table 23-7 women to gradually increase their activity level Modified Heart Rate Target Zones for Aerobic Exercise in Pregnancy (i.e., previously sedentary women should begin with 15 minutes of continuous exercise three Maternal Age Heart Rate Target Zone Heart Rate Target Zone times a week, increasing gradually to 30-minute (beats/min) (beats/10 seconds) Less than 20 140–155 23–26 sessions four times a week). Table 23-8 pres- 20–29 135–150 22–25 ents the joint recommendations of SOGC and 30–39 130–145 21–24 CSEP for exercise in pregnancy and the post- 40 or greater 125–140 20–23 partum period. Note: The most appropriate use of these modified heart rate guidelines is in conjunction with RPE, as blunted, exaggerated, and normal linear responses to exercise have been observed Biomechanical at different stages during pregnancy. Considerations for the Source: Society of Obstetricians and Gynaecologists of Canada (SOGC) & Canadian Pregnant Mother Society for Exercise Physiology (CSEP) (2003). Joint SOGC/CSEP clinical practice guideline: Exercise in pregnancy and the postpartum period. Journal of Obstetrics and Gynaecology Canada, 25, 6, 516–522. ue to the wide range of postural and physiological adaptations that occur Dduring pregnancy, the ACE-AHFS must Table 23-8 be proficient at designing exercise programs geared Recommendations for Exercise in Pregnancy and the toward making physical activity more comfort- Postpartum Period able for this population. Physiological adaptations • All women without contraindications should be encouraged to include a profound increase in body mass, reten- participate in aerobic and strength-conditioning exercises as part tion of fluid, and laxity in supporting structures. of a healthy lifestyle during their pregnancy. Postural adaptations correspond with these physi- • Reasonable goals of aerobic conditioning in pregnancy should ological changes and usually entail an alteration in be to maintain a good fitness level throughout pregnancy without the loading and alignment of, and muscle forces trying to reach peak fitness or train for an athletic competition. along, the spine and weightbearing joints. During • Women should choose activities that will minimize the risk of loss pregnancy, production of the hormone relaxin of balance and fetal trauma. increases tenfold. The hormone creates joint • Women should be advised that adverse pregnancy or neonatal laxity, which not only allows the pelvis to accom- outcomes are not increased for exercising women. modate the enlarging uterus, but also weakens the ability of static supports in the lumbar spine to • Initiation of pelvic floor exercises in the immediate postpartum period may reduce the risk of future urinary incontinence. withstand shearing forces. In the pelvis, joint laxity is most prominent in the symphysis pubis and the • Women should be advised that moderate exercise during lactation sacroiliac joints. does not affect the quantity or composition of breast milk or impact infant growth. Typically, it is thought that advancing preg- nancy produces a forward shift in the center of Validation: This guideline has been approved by the Society of Obstetricians and Gynaecologists of Canada (SOGC) Clinical Practice Obstetrics Committee, the Executive gravity followed by an anterior pelvic tilt and sub- and Council of SOGC, and the Board of Directors of the Canadian Society for Exercise sequent increase in lumbar lordosis and thoracic Physiology (CSEP). kyphosis. However, research on postural changes Sponsors: This guideline has been jointly sponsored by the SOGC and the CSEP. associated with prenatal weight gain does not Source: Society of Obstetricians and Gynaecologists of Canada (SOGC) & Canadian confirm this line of thinking (Perkins, Hammer, Society for Exercise Physiology (CSEP) (2003). Joint SOGC/CSEP clinical practice & Loubert, 1998; Dumas et al., 1995; Moore, guideline: Exercise in pregnancy and the postpartum period. Journal of Obstetrics and Gynaecology Canada, 25, 6, 516–522. Dumas, & Reid, 1990). After the first trimester, the uterus can no longer be contained within the pelvis and moves superiorly and anteriorly. As lumbar lordosis; however, studies have shown that pregnancy progresses, the biomechanical altera- the lordosis remains the same or increases only tions of increased abdominal girth and weakened slightly (Hummel, 1987). Instead, it appears that abdominal muscles were thought to increase the entire spine shifts to a more posterior position

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and the center of gravity as a whole tends to move pregnancy makes other forms of physical activity in a posterior and caudal direction. In fact, one uncomfortable or stressful on the joints. study showed that 75% of women demonstrated a In addition to low-back pain, common muscu- more posterior posture, wherein the weight of the loskeletal complaints that arise during pregnancy uterus was carried posterior to the normal center include sacroiliac (SI) joint dysfunction, pubic of gravity (Perkins, Hammer, & Loubert, 1998). pain, nerve compression syndromes, diastasis As noted previously, a large majority of women recti, and stress urinary incontinence. The complain of low-back pain during pregnancy remainder of this section covers each of these con- (Brynhildsen, 1998; Kristiansson, Svardsudd, & ditions in more detail. von Schoultz,1996; Perkins, Hammer, & Loubert, 1998). Prenatal low-back and pelvic pain appear Low-back and Posterior Pelvic Pain to be more related to pre-pregnancy postural The two most common sites of back pain in habits that are exaggerated during gestation than pregnancy are the lumbar and posterior pelvic to postural adaptations to pregnancy. Laxity in the areas. Back pain occurs most commonly after the supporting tissues, either pre-existing or enhanced sixth month and can last until the sixth month by the hormone relaxin, becomes greater in the postpartum. After 12 weeks of pregnancy, the direction of habitual posture (Dumas et al., 1995). uterus can no longer be contained within the In other words, pronated feet may become flatter, pelvis and the mass moves superiorly and ante- hyperextended knees may become more pro- riorly. As the abdominal muscles are stretched nounced, and spinal curves may soften. Increased and tone is diminished, they lose their ability ligament laxity has been postulated as a cause to contribute effectively to the maintenance of for back and pelvic pain, particularly if the pain neutral posture. In the lumbar spine, joint laxity begins early in the pregnancy before an increase is most notable in the anterior and posterior lon- in body mass is evident (Damen et al., 2002; gitudinal ligaments. This weakens the ability of Bullock-Saxton, 1998). During the term of their static supports in the lumbar spine to withstand pregnancies, most women adapt to these postural the shearing forces. As a result, there may be an and physiological changes and, following the increase in discogenic symptoms and/or pain baby’s delivery, return to their pre-pregnant states. coming from the facet joints. To alleviate the postural discomforts of exercise, Lumbar pain during pregnancy is defined as many pregnant women choose to work out in the back pain from the lumbar area only, with or water. Women who participate in a water exer- without radiation to the legs. Sciatica is rare and cise class have been shown to experience reduced thought to account for only 1% of low-back pain symptoms of back pain during late pregnancy and in pregnancy (Östgaard, Andersson, & Karlsson, miss fewer days at work compared to a control 1991; Hainline, 1994). In general, lumbar pain group (Kihlstrand et al., 1999). Aquatic exercise during pregnancy is similar to low-back pain expe- in relatively cool water decreases the rise in body rienced by non-pregnant women. This type of temperature observed during land-based exercise, pain typically increases with such prolonged pos- which can help minimize the risk of hyperther- tures as sitting, standing, and repetitive lifting. mia (McMurray & Katz, 1990). The hydrostatic Exercises appropriate for pregnant women pressure exerted on a pregnant woman’s body with lumbar pain include mobility and stretch- during pool exercise may lessen fluid retention ing movements that emphasize relaxing and and swelling, and the buoyancy of water supports lengthening the back extensors, hip flexors, the bodyweight, relieving pressure on the weight- scapulae protractors, shoulder internal rotators, bearing joints and allowing the muscles relief from and neck flexors. Strengthening exercises should bearing extra mechanical stress during the preg- focus on the abdominals, gluteals, and scapulae nancy. Thus, water exercise is a valuable option retractors to reinforce their ability to support for women to consider, especially as advancing proper alignment.

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Posterior pelvic pain is four times more preva- by sacroiliac, low-back, and suprapubic pain. lent than lumbar pain in pregnancy and is thought Weightbearing activities, particularly those that to be caused by SI joint dysfunction. Sacroiliac involve lifting one leg, intensify the pain. Women pain is felt distal and lateral to the lumbar spine, also may hear or feel a clicking or grinding sen- with or without lower-extremity radiation, and sation in the joint, and there is often difficulty can occur on one or both sides of the sacrum. walking, so that a “waddling” gait is adopted. Women with sacroiliac pain as their primary As noted previously, it has been suggested that complaint tend to have low-back pain for a longer pelvic instability is the primary cause of pelvic duration than those who simply have lumbar (sacroiliac and symphysis pubis) joint pain during pain. They also tend to experience symptoms for pregnancy (Fast et al., 1990; Svensson et al., 1990). several months after delivery (Hainline, 1994). Pregnancy-related connective tissue changes and Occupational activities that involve prolonged the change in the center of gravity result in length- postures at extreme ranges, such as sitting at a ening, and thus weakening of the ligaments of the computer and leaning forward or standing and pelvic joints, the thoracolumbar fascia, and the leaning over a desk or workstation, increase the surrounding muscles, all of which provide stability risk of developing posterior pelvic pain during to the pelvic ring. Normally, the pre-pregnancy pregnancy. Unlike other forms of low-back pain width of the pubic symphysis is 0.5 mm. As preg- during pregnancy, a previous high level of fitness nancy progresses, the symphysis pubis continues does not necessarily prevent this problem. to widen to a maximum of approximately 12 mm. The hypothetical origins of SI joint dysfunction With this widening, there is the risk of vertical during pregnancy focus on decreased stability of displacement of the pubis, and the possibility of the pelvic girdle. It is assumed that the stability of rotatory stress on the sacroiliac joints. During the pelvic girdle is provided, in part, by the coarse delivery, partial symphyseal separations and texture of the SI cartilage surfaces, the undulated complete dislocations are possible, resulting in a shape of the joint, and the compressive forces of greater concern for postnatal exercisers. the muscles, ligaments, and thoracolumbar fascia. Treatment of pubic symphysis dysfunction Muscles that generate a force perpendicular to includes avoidance of weightbearing activities that the SI joints or increase tension on the sacroiliac intensify pain, a physician evaluation, and physical ligaments or thoracolumbar fascia generate forces therapy. Pelvic belts, which compress the pelvis that may act to stabilize the SI joint. These include and minimize motion in the symphysis pubis and the internal and external abdominal obliques, the SI joint, may be prescribed. latissimus dorsi, the transversospinal parts of the erector spinae muscle (especially the multifidus), Carpal Tunnel Syndrome and the gluteus maximus. Therefore, functional The most common neurological disorder exercise programs that target this musculature during pregnancy is carpal tunnel syndrome. may benefit women with prenatal pelvic pain, Symptoms include pain and paresthesias in the partly by increasing muscle force and endurance median nerve distribution (thumb, index, and (Snijders, Vleeming, & Stoeckart, 1993a; Snijders, middle fingers), as the nerve becomes depressed Vleeming, & Stoeckart, 1993b; Vleeming et al., as it passes through the carpal tunnel in the 1995; Vleeming, Stoeckart, & Snijders, 1989; wrist. Carpal tunnel syndrome is very common Vleeming et al., 1989; Vleeming et al., 1996). and most often occurs in women aged 30 to 50. Emergence or worsening of carpal tunnel Pubic Pain syndrome may occur during pregnancy. The The irritation of the pubic symphysis caused by presumed mechanism is pressure on the median increased motion at the joint is called symphysi- nerve within the carpal compartment at the wrist tis. Symptoms include mild to severe pain in the as a result of tissue swelling, secondary to the fluid pubic region, groin, and medial aspect of the thigh retention that occurs during pregnancy. Women (unilateral or bilateral), frequently accompanied who develop carpal tunnel syndrome in pregnancy

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are not likely to develop it again, unless there is physical exertion. The most common test for another pregnancy. The condition usually discon- diastasis recti is performed by placing two fingers tinues after delivery. horizontally on the suspected location while Treatments include ergonomic improvements, the client lies supine with the knees bent and analgesia, splinting, and sometimes corticosteroid performs a curl-up. If the fingers can penetrate injection or surgery. Since activities or jobs that at the location, there is probably a split. The require repetitive flexion and extension of the degree of separation is measured according to wrist may contribute to carpal tunnel syndrome, the number of fingerwidths of the split. One to these activities should be minimized. Care should two fingerwidths is considered normal, whereas be taken to avoid loading the wrist in hyperex- greater than three fingerwidths is excessive and tension, grasping objects tightly, and repetitive care should be taken to avoid placing a direct line flexion and extension of the wrist during exercise. of stress on the area. Abdominal compression Keeping the wrist in its neutral position during exercises and curl-ups in a semirecumbent posi- physical activities such as weightlifting should tion may be helpful for strengthening the rectus provide a comfortable, non-aggravating option for abdominis in this situation. pregnant exercisers. Stress Urinary Incontinence Diastasis Recti Stress urinary incontinence (SUI) is the Diastasis recti is a partial or complete separation involuntary loss of urine that occurs with physi- between the left and right sides of the rectus abdo- cal exertion and a rise in abdominal pressure. minis muscle. During pregnancy, the maternal Coughing, sneezing, straining, laughing, and inferior thoracic diameter is increased, thus alter- impact activities such as jumping and running ing the spatial relationship between the superior are events commonly associated with SUI. The and inferior abdominal muscle attachments. In pelvic-floor muscles are considered important in addition, anterior and lateral dimensions of the maintaining pelvic organ support and bowel and abdomen during pregnancy increase the distance bladder continence. Several studies have shown between muscle attachments, producing increases that women with urinary incontinence have in muscle length. In some women, the rectus decreased pelvic floor muscle thickness and elec- abdominis muscles move laterally and may remain tromyographic activity, and less muscle strength separated in the immediate post-delivery period. compared with control subjects without urinary Diastasis recti is commonly seen in women incontinence (Bernstein, 1997; Hoyte et al., 2004; who have multiple pregnancies, because the Aanestad & Flink, 1999; Morkved, Schei, & muscles have been stretched many times. Extra Salvesen, 2003; Morin et al., 2004). skin and soft tissue in the front of the abdominal During pregnancy and delivery, the prolonged wall may be the only signs of this condition in stretching and trauma sustained by the pelvic early pregnancy. In late pregnancy, the top of the floor musculature and the concomitant neural pregnant uterus is often seen bulging out of the damage thought to accompany this stretching abdominal wall. Three main factors contribute to can reduce the strength of the pelvic floor. These the incidence and severity of diastasis recti during changes interfere with the normal transmission of pregnancy: maternal hormones (relaxin, estrogen, information regarding changes in abdominal pres- and progesterone), mechanical stress within the sure to the proximal urethra, thereby predisposing abdominal cavity due to increasing girth, and the woman to SUI. Five risk factors predispose a weak abdominal muscles (strong abdominal mus- woman to postpartum SUI: Multiple pregnancies, cles are more likely to resist this condition). vaginal delivery, high infant birth weight While some rectus abdominis separation is a (>8.1 lb; 3.7 kg), large infant cranial circumfer- normal part of every pregnancy, too much sepa- ence (>13.8 inches; 35.5 cm), high maternal ration may lead to diminished muscular force weight gain during pregnancy (>28.6 lb; 13 kg), production and even more separation during and tearing of the perineum during delivery.

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Women experiencing SUI during pregnancy and/ been reported (ACOG, 2002b; Clapp, Lopez, or childbirth are generally thought to have a greater & Harcar-Sevcik, 1999). As a precaution to risk of developing the condition later in life. help avoid hypoglycemia, pregnant women Treatment of SUI during and after pregnancy should be reminded to consume a pre-exercise includes the performance of Kegel exercises to snack and eat frequent small meals throughout strengthen the pelvic-floor muscles. Since the the day, especially later in pregnancy. Pregnant introduction of Kegel exercises in 1948, the exercisers should be made aware of the signs efficacy of pelvic-floor muscle strengthening of hypoglycemia, such as weakness, dizziness, in the treatment of SUI has been supported by fatigue, and nausea. the findings of several randomized controlled The position of the American Dietetic studies and systematic reviews (Burns et al., Association (ADA) on nutrition during preg- 1993; Bo, Talseth, & Holm, 1999; Henalla et nancy maintains that the key components of al., 1989; Goode et al., 2003; Hay-Smith et al., a healthy lifestyle during pregnancy include 2002). The benefits of an effective Kegel exer- appropriate weight gain (Table 23-9); con- cise regimen include providing support for the sumption of a variety of foods in accordance pelvic organs; preventing prolapse (falling) of the with the MyPlate Food Guidance System; bladder, uterus, and rectum; supporting proper appropriate and timely vitamin and mineral pelvic alignment; reinforcing sphincter control; supplementation; avoidance of tobacco, alco- enhancing circulation to the pelvic floor muscles; hol, and other harmful substances; and safe and providing a healthy environment for the food-handling practices (ADA, 2002). The healing process after labor and delivery (Dunbar, ADA recommends that pregnant women eat a 1992). Women who exercise during pregnancy total of 2500 to 2700 calories per day, and that and resume it early in the postpartum period those calories should come from a variety of have a shorter duration of SUI than those who healthy foods. Additionally, women consider- do not (Morkved & Bo, 2000). ing becoming pregnant need to ensure that they Nutritional Considerations are consuming adequate amounts of folic acid, iron, calcium, vitamin D, and water to sustain fter the thirteenth week of pregnancy, health before, during, and after pregnancy. The approximately 300 additional calo- ACE-AHFS should encourage pregnant clients Aries per day are required to meet the to consult with their physicians in the area of metabolic needs of pregnancy. Weightbearing nutrition during pregnancy. For a more detailed exercise, such as walking, increases the energy analysis of nutrition concerns in pregnancy, requirement even further. Furthermore, as the pregnancy progresses, the caloric needs Table 23-9 of the mother progressively increase in cor- Appropriate Weight Gain During Pregnancy respondence with the increase in body weight. An added concern related to nutrition during Weight Classification Weight Gain Goal* pregnancy is adequate carbohydrate intake. Underweight About 28 to 40 pounds (13 to 18 kg) Pregnant women use carbohydrates at a greater Normal weight About 25 to 35 pounds (11 to 16 kg) rate both at rest and during exercise than do Overweight About 15 to 25 pounds (7 to 11 kg) non-pregnant women (Clapp et al., 1988; Obese At least 15 pounds (7 kg) Soultanakis, Artal, & Wiswell, 1996). Since maternal blood glucose is the fetus’ primary * Women should talk to their healthcare providers about how much weight they should gain during pregnancy. The general weight-gain recommendations listed energy source, there is concern that low mater- here refer to weight before pregnancy and are for women expecting only one nal blood glucose could compromise fetal baby. energy supply. However, intrauterine growth Source: U.S. Department of Health and Human Services, National Institutes of retardation, or other short- or long-term effects Health. Fit for Two: Tips for Pregnancy. win.niddk.nih.gov/publications/two.htm. on newborns of exercising mothers, have not

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refer to the American Dietetic Association’s family. Women who have postpartum depres- position statement: “Nutrition and Lifestyle for sion are significantly more likely to experience a Healthy Pregnancy Outcome” (ADA, 2002). future episodes of depression (Cooper & Murray, Psychological 1995), and infants and children are particularly vulnerable to difficulties with maternal bonding Considerations and developmental problems because of impaired maternal-infant interactions and negative percep- regnancy is associated with increased tions of infant behavior. The cause of postnatal psychological distress for many women, depression is unclear. However, research suggests Pwhich includes increased anxiety, the influence of psychosocial and psychological depression, and fatigue. Investigations that mea- risk factors, such as life stress, unemployment, sured depressive symptoms throughout pregnancy marital conflict, maternal self-esteem, and lack of have shown that depression is more common social support (O’Hara & Swain, 1996; Cooper during the third trimester and that an overwhelm- & Murray, 1997; Beck, 2001; Bernazzani et al., ing majority (97%) of women report fatigue as 1997; O’Hara et al., 1991; Gotlib et al., 1991). a concern at some point during their pregnancy A disorder related to postpartum depression, (Evans et al., 2001; Zib, Lim, & Walters, 1999). In but considered not as severe, is called “maternity most societies, it is a long-held belief that a moth- blues.” Maternity blues refers to the tearful- er’s psychological state can influence her unborn ness, irritability, hypochondriasis, sleeplessness, baby. Some studies have shown that babies of impairment of concentration, and headache that stressed or anxious mothers have a significantly occurs in the 10 days or so postpartum. A peak in lower average birth weight for gestational age and symptoms typically occurs around the fourth to tend to be born early (Perkin et al., 1993; Wadwa fifth day after delivery, coinciding with maximal et al., 1993; Copper et al., 1996; Hedegaard et al., hormonal changes, which include falling concen- 1996). This is an area of concern because low trations of progesterone, estradiol, and cortisol birth weight seems to be associated with health and rising prolactin concentrations. During problems in later life (e.g., hypertension and isch- pregnancy, progesterone concentrations slowly emic heart disease) (Barker, 1995). Furthermore, rise to a maximum until they reach levels several ultrasound studies have shown that fetal behav- hundred times higher than normal. After delivery ior is affected by maternal anxiety (Ianniruberto and the withdrawal of the placenta, there is a & Tajani, 1981; Groome et al., 1995). It has precipitous drop in progesterone concentration. been proposed that maternal stress or anxiety It is hypothesized that the symptoms of mater- might affect the fetus through increased concen- nity blues are related to progesterone withdrawal trations of maternal hormones being transported (Harris et al., 1994). Cortisol concentrations directly across the placenta (Gitau et al., 1998). also rise during pregnancy to several times their In addition, blood flow to the baby may be normal values. They rise further during the stress impaired through the uterine arteries with high of labor and then slowly return to normal within levels of maternal anxiety, which would con- 15 days of delivery. tribute to the low birth weights associated with As noted earlier, many previously active women psychologically distressed mothers (Teixeira, stop exercise or significantly reduce it during preg- Fisk, & Glover, 1999). nancy (Zhang & Savits, 1996; Ning et al., 2003). Another major psychological concern for many Given the known links between physical inactiv- women is postpartum or postnatal depression. ity and reduced mental health, it is plausible that Postnatal depression affects approximately 10 to a relationship exists between pregnancy-related 13% of women in the early weeks postpartum, reductions in physical activity and psychological with episodes typically lasting two to six months. distress. A small number of investigations have This depressive disorder has well-documented found that low physical activity is associated with health consequences for the mother, child, and higher scores on anxiety, depression, and fatigue

ACE Advanced Health & Fitness Specialist Manual Pre- and Postnatal Exercise Chapter twenty-three 589 scales during pregnancy (DaCosta et al., 2003; a mother’s ability to successfully breastfeed. Goodwin, Astbury, & McMeeken, 2000; Koniak- Another potential risk of postnatal exercise Griffin, 1994; Wallace et al., 1986). In a study involves new mothers who deliver their babies that measured physical activity and mood during via C-section. If physical activity is resumed pregnancy, it was shown that healthy women who prematurely, there is a risk of disrupting post- maintain an above-average level of physical activ- surgery healing. ity during the second and third trimesters enjoy Epidemiological studies have shown an asso- more mood stability (Poudevigne & O’Connor, ciation between higher levels of physical activity 2005). These findings support the theory that reg- in the postpartum period and a return to pre- ular endurance exercise throughout pregnancy not pregnancy body weight, as well as an increased only improves maternal and fetal physical health, loss of pregnancy-associated weight gain (Ohlin but may enhance psychological health as well. & Rossner, 1996; Sampselle et al., 1999; Harris, Benefits and Risks of Ellison, & Clement, 1999). A randomized control study that compared the effect of a combina- Exercise Following tion of diet (500 calories less than predicted total Pregnancy energy expenditure) plus exercise to no interven- tion on weight loss and body composition in egular exercise is as beneficial in the overweight lactating women found that the com- postpartum period as it is at other times bined diet and exercise intervention resulted in Rin a woman’s life. The possible benefits significantly greater weight and fat loss compared include the following: with the control group (Lovelady et al., 2000). • Preventing obesity (or overweight) through Research is lacking on maternal aerobic fit- promotion of body fat/body weight loss ness and strength during the postpartum period. • Promoting aerobic fitness and strength, However, two randomized controlled trials have leading to an improved ability to perform found a significant increase in aerobic capacity activities of mothering resulting from an endurance-exercise interven- • Optimizing bone health by increasing bone tion during the first 10 to 12 weeks postpartum mineral density and/or preventing lactation- (Dewey et al., 1994; Lovelady et al., 2000). associated bone loss To date, studies have not assessed the effect of • Improving mood or self-esteem strength training (with or without aerobic exer- Furthermore, a mother’s participation in regu- cise) during the postpartum period on muscle lar exercise after childbirth may encourage regular strength and endurance or the preservation of lean physical activity in her children. body mass. It seems reasonable to state, however, A theoretical risk of postpartum exercise is that the possible benefit of maternal fitness on the that strenuous activity in women who breastfeed daily physical activities of mothering, including may alter the quality (e.g., macronutrient and lifting, carrying, or running after a child, is worth micronutrient composition, immunological prop- the effort of beginning or maintaining regular erties, accumulation of exercise by-products) or exercise during the postpartum period. quantity of their milk. However, a review of the Lactation in the two-to-six-month postpar- literature pertaining to breast milk production tum period is associated with axial bone loss. and composition in relation to postnatal exercise It is speculated that these changes result from revealed that there were no remarkable differ- the prolonged lactation-induced estrogen defi- ences in the breast milk of women who performed ciency, combined with the “calcium drain” of submaximal exercise, maximal exercise, or who breastfeeding (an additional 200 to 400 mg per were physically inactive (Larson-Meyer, 2002). day of calcium is required during lactation). The author of the review concluded that several It is unclear whether exercise can attenuate or studies have collectively determined that neither prevent lactation-associated bone loss. Research acute nor regular exercise has adverse effects on demonstrates, however, that bone loss recovers in

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healthy women with the cessation of lactation and water compartments of the body (making it likely the return of normal menses (Cross et al., 1995; to diffuse into breast milk). Research in this area Sowers et al., 1993; Ritchie et al., 1998). has been inconclusive due to inconsistent reports As noted previously, dealing with the hormonal of lactic acid concentrations in breast milk and changes and fatigue associated with becom- study results showing that infant acceptance of ing a new mother often results in emotional breast milk is not reduced after submaximal or distress. Some women have trouble finding the maximal exercise (Carey, Quinn, & Goodwin, time or energy to exercise, and some feel guilty 1997; Quinn & Carey, 1999; Carey & Quinn, about being away from the baby to exercise. 2001; Wright, Carey, & Quinn, 1999). Longitudinal studies suggest that the incidence With regard to exercising after childbirth, a of significant postpartum depression is lower in major consideration is the method of delivery. exercising women compared with inactive con- Women who have undergone C-section have had trols (Clapp, 2002). The author hypothesized that major abdominal surgery that results in pain and depression occurs less in physically active women tenderness in the abdomen, as well as consider- because exercise gives them a regular break from able fatigue. The current thinking on recovery the 24-hour, seven-day-a-week commitment and rehabilitation after C-section is that walk- that comes with a new infant. In other words, ing as soon as possible after the surgery helps to physically active postpartum women appear less minimize muscle wasting, increase circulation, overwhelmed and more ready to master mother- and speed the healing process. Additionally, deep hood. It has also been reported that exercising breathing, abdominal compression exercises, women have a more positive self-image during and and Kegels can be resumed early in the recovery after pregnancy than do non-exercising women process. Many women are ready to introduce (Clapp, 2002). Additionally, among postnatal intermittent walking or other gentle forms of women, an acute bout of aerobic exercise has been exercise by two weeks postpartum, with the degree shown to lead to decreases in acute transitory of discomfort, fatigue, and motivation guiding anxiety and depression as well as increases in vigor activity levels. Vigorous exercise is contraindi- (Koltyn & Schultes, 1997). cated after a C-section until the recovery and Research on the quantity and quality of breast rehabilitation process is complete. Re-entry into a milk in physically active women has found structured fitness program should be postponed no affect on the volume (adjusted for infant’s until a physician’s clearance has been obtained weight) or the energy density or energy composi- after the six-week postpartum check-up. tion (protein, lipid, and lactose) of breast milk Physiological Changes in non-overweight women training vigorously or in overweight women randomly assigned to Following Pregnancy an exercise and calorie-restriction intervention (Lovelady, Lonnerdal, & Dewey, 1990; Lovelady s in pregnancy, the physiological et al., 2000). These investigations also found no changes following pregnancy are pri- differences in body weight or growth among Amarily determined by the endocrine infants whose mothers were in either the exercise system. The hormones that dominate during or control groups. As a result of anecdotal reports pregnancy return to pre-pregnancy levels after from mothers who claimed that their babies often childbirth, which results in concomitant changes had a difficult time breastfeeding post-workout, in the musculoskeletal, cardiovascular, and respi- researchers examined the levels of lactic acid accu- ratory systems. mulation in breast milk after exercise (Wallace, The hormone relaxin, responsible for produc- Inbar, & Ernsthausen, 1992). Lactic acid may ing laxity in the collagenous structures of the have initially been targeted among other metabo- pelvis and other areas in preparation for child- lites that increase with exercise (e.g., hydrogen ion birth, rises to 10 times its normal level during and ammonia) because it readily diffuses into the pregnancy. While the research is not clear on

ACE Advanced Health & Fitness Specialist Manual Pre- and Postnatal Exercise Chapter twenty-three 591 how long it takes for relaxin to subside to pre- and does not compromise neonatal weight gain pregnancy levels after delivery, ligamentous (McCrory et al., 1999). overstretching can remain in a new mother for Programming Guidelines and up to eight months postpartum. For this reason, a new mother should learn how to correctly lift Considerations for Postnatal and carry her baby, put the baby in the crib, and Exercise take the baby out of the crib to reduce the risk of back pain due to the relaxed soft-tissue structures rom an analysis of the available physiologi- supporting the joints. cal data in the perinatal period, ACOG During pregnancy, the cardiovascular system Fhas developed guidelines for postpartum adapts by increasing blood volume, heart rate, exercise. The guidelines are very general and state and cardiac output. Plasma volume increases that many of the physiological and morphologi- by as much as 40 to 50% and red cell volume cal changes of pregnancy persist four to six weeks goes up by 15 to 20% to maintain the increased postpartum, and recommend that pre-pregnancy circulatory need of the enlarging uterus and exercise routines be resumed gradually based fetoplacental unit, fill the ever-increasing on the woman’s physical capabilities (ACOG, venous reservoir, and protect the mother 2002b). A more detailed set of guidelines for from the blood loss at the time of delivery. postnatal exercise has been developed by Clapp It takes about eight weeks after delivery for (2002), who suggests that the initial goal of the blood volume to return to pre-pregnancy exercise (within the first six weeks) is to obtain levels. Cardiac output increases by 30 to 40% personal time and redevelop a sense of control. during pregnancy, with the maximum increase This can be accomplished by doing the following: attained at 24 weeks of gestation. The increase • Beginning slowly and increasing gradually in heart rate lags behind the increase in cardiac • Avoiding excessive fatigue and dehydration output initially, and then ultimately increases • Supporting and compressing the abdomen by 10 to 15 bpm by 28 to 32 weeks of gestation. and breasts Cardiac output, heart rate, and stroke volume • Stopping to evaluate if it hurts decrease to pre-labor values 24 to 72 hours after • Stopping exercise and seeking medical evalu- birth and return to non-pregnant levels within ation if the postpartum client is experiencing six to eight weeks after delivery. bright red vaginal bleeding that is heavier The respiratory system exhibits adaptations than a menstrual period to pregnancy starting as early as the fourth Clapp goes on to suggest that after six weeks week of gestation. A woman can expect minute postpartum, the goal of the exercise regimen in ventilation to increase by about 50% above non- the remainder of the first year following birth is to pregnant values and tidal volume and respiratory improve physical fitness. Other recommendations rate to also increase during pregnancy. Within suggest that, if pregnancy and delivery are uncom- six to 12 weeks postpartum, all respiratory plicated, a mild exercise program consisting of parameters return to non-pregnant values. walking, pelvic floor exercises, and stretching may Because of the gradual return to pre-pregnancy begin immediately (Kochan-Vintinner, 1999). musculoskeletal, cardiovascular, and respira- However, if delivery was complicated or was by tory parameters, and the detraining effect that C-section, a physician should be consulted before occurs for most women during pregnancy, resuming pre-pregnancy levels of physical activity, postpartum exercise programs should be indi- usually after the first postpartum check-up at six vidualized and resumed gradually. There are no to eight weeks (Kochan-Vintinner, 1999). known maternal complications associated with One area of concern for many women after the resumption of exercise training postpartum childbirth is strengthening the pelvic floor. It is (Hale & Milne, 1996). Furthermore, moderate estimated that up to three months after delivery, weight reduction while nursing is considered safe 20 to 30% of women have SUI and about 4%

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have fecal incontinence (Wilson, Herbison, & • Tightening the pelvic floor muscles and hold- Herbison, 1996; MacArthur, Lewis, & Bick, ing a static contraction for a count of 10 1993; MacArthur, Bick, & Keighley, 1997; Sultan • Relaxing the muscles completely for a count et al., 1993). The pelvic-floor muscles form the of 10 pelvic basin and help maintain continence by • Performing 10 Kegel exercise sets, three times actively supporting the pelvic organs and clos- per day ing the pelvic openings when contracting. The Another option is to perform the Kegel exer- pelvic-floor muscles are composed of the pelvic cises quickly (tighten, lift up, and let go) to work diaphragm muscles (together known as the levator the muscles in a way that mimics shutting off the ani), which can be referred to as the deep layer; the flow of urine to help prevent accidents. Many urogenital diaphragm muscles (together known women prefer to do these exercises while lying as the perineal muscles), which can be referred to down or sitting in a chair, but they can be per- as the superficial layer; and the urethral and anal formed anywhere. After four to six weeks, there is sphincter muscles (Figure 23-1). The pelvic-floor usually some improvement, but it may take up to muscles are encased in fascia, which is connected three months to see a significant change. to the endopelvic (parietal) fascia surrounding the Training the pelvic-floor musculature goes hand- pelvic organs and assists in pelvic organ support. in-hand with performing exercises to strengthen Correct action of the pelvic-floor muscles has the core. Research findings have shown that been described as a squeeze around the pelvic maximum pelvic-floor muscle contractions are not openings and an inward lift (such as the action possible without a co-contraction of the abdominal performed during a Kegel exercise). Pelvic-floor muscles, specifically the transversus abdominis and muscle training can increase the strength of the internal oblique muscles (Bo et al., 1990; Neumann Figure 23-1 pelvic-floor muscles, thereby enhancing the struc- & Gill, 2002). This abdominal contraction can be Pelvic floor muscles (inferior view) tural support, timing, and strength of automatic observed as a small inward movement of the lower contraction and resulting in the reduction or elim- abdomen. Prior to any strenuous abdominal exer- Source: © ination of leakage. Initially, Kegel exercises can be cise, postnatal clients should perform transversus Anatomedia Pty Ltd. (www.anatomedia. performed utilizing the following three steps: abdominis work (i.e., a drawing-in maneuver), com) pelvic tilts, and spinal stabilization exercises. Since traditional abdominal crunches compress the abdominal space and increase pressure on the Urogenital diaphragm pelvic floor, they should be reserved for exercise with perineal muscles regimens after the postnatal client has had time to re-educate the pelvic floor muscles through Kegel training and core stabilization work. Biomechanical Considerations for the Lactating Mother

ncreased weight in the breasts from lactation, coupled with the forward-rounded postures Iassociated with holding, feeding, and cuddling the baby, may lead to upper-back pain in a new mother. Additionally, lifting car seats and push- ing strollers with handles that are set too low can contribute to the back pain often reported after Levator ani childbirth. Stretches for the anterior shoulder Pubococcygeus, Iliococcygeus Gluteus maximus girdle, followed by scapular retraction and external

ACE Advanced Health & Fitness Specialist Manual Pre- and Postnatal Exercise Chapter twenty-three 593 shoulder rotation exercises, are appropriate for experienced in her first two pregnancies. Mrs. S. new mothers looking to improve posture post- may continue her resistance-training program, delivery and ease the pain associated with these but may find lighter resistance and higher repeti- biomechanical concerns. tions more comfortable than a higher-intensity Good breast support is important for comfort program. She should be instructed to avoid pro- during postpartum exercise. It is recommended longed exercise in the supine position after the that postnatal exercisers wear a very supportive first trimester. exercise bra, or two bras together if necessary. Exercises appropriate for Mrs. S. that will Furthermore, breastfeeding women are advised to help her avoid low-back pain include mobil- avoid exercise with a breast abscess or with pain- ity and stretching movements that emphasize ful, engorged breasts. Nursing or expressing milk relaxing and lengthening the back extensors, hip before exercise has also been suggested to increase flexors, scapulae protractors, shoulder internal comfort during exercise. rotators, and neck flexors. Strengthening exer- Case Study cises should focus on the abdominals, gluteals, and scapulae retractors to reinforce their abil- acki S. is 37 years old and has recently ity to support proper alignment. Specifically, discovered she is pregnant. She is in her abdominal compression exercises and curl-ups Jfirst trimester and would like to continue in a semirecumbent position may be helpful for her exercise program. Currently, Mrs. S. runs 3 strengthening the rectus abdominis without to 4 (5 to 6 km) miles per workout for a total of exacerbating her diastasis recti. about 12 to 15 (19 to 24 km) miles per week, Summary and lifts weights two days a week. She has been cleared by her physician to continue her cur- n increasing amount of research on rent routine as long as she reduces her exercise exercise in pregnancy has led to less as overall discomfort dictates. Mrs. S. has two A debate regarding the maternal and fetal children already, and during both pregnancies risks of regular physical activity during pregnancy. suffered from mild diastasis recti and lumbar Women entering pregnancy with regular aerobic back pain. and strength-conditioning activities as a part of Frequency: Mrs. S. may continue to exercise at their daily routines is a growing trend, and many least three times per week following her typical women who are not physically active view preg- exercise routine. nancy as a time to modify their lifestyles to include Intensity: Mrs. S. should use RPE to moni- more health-conscious activities. tor the intensity of her workout and aim for a Evidence that regular prenatal exercise is an rating of “fairly light” to “somewhat hard,” or 11 important component of a healthy pregnancy is to 13 on Borg’s 6 to 20 scale. She should also be increasing. The positive affects of exercise during instructed to avoid hot and humid conditions pregnancy on the musculoskeletal, cardiovascu- and remain properly hydrated. lar, respiratory, and thermoregulatory systems Time: Mrs. S. should be encouraged to exer- have been reported. Several national health and cise in accordance with her regular exercise medical organizations have published recommen- program. However, she should be instructed dations and guidelines on exercise and pregnancy not to continue an exercise session to the point (ACOG, 2002b; ACSM, 2010; SOCG & CSEP, of fatigue or exhaustion. 2003). According to ACOG (2002b), there are Type: Mrs. S. may continue to perform weight- some women for whom exercise during pregnancy bearing exercise, including running, as long as she is absolutely contraindicated, and others for is comfortable. As her pregnancy progresses, she whom the potential benefits associated with exer- may want to perform non-weightbearing exercise cise may outweigh the risks. such as cycling or water aerobics, especially if she Due to the wide range of postural and physi- notices a recurrence of the low-back pain she ological adaptations that occur during and after

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pregnancy, the ACE-AHFS must be proficient changes and usually entail an alteration in the at designing exercise programs geared toward loading and alignment of, and muscle forces along, making physical activity more comfortable for the spine and weightbearing joints. this population. Physiological adaptations include For more detailed information on exercise and a profound increase in body mass, retention of pregnancy, refer to Pre- and Post-Natal Fitness: A fluid, and laxity in supporting structures. Postural Guide for Fitness Professionals from the American adaptations correspond with these physiological Council on Exercise, available at www.acefitness.org.

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ACE Advanced Health & Fitness Specialist Manual Pre- and Postnatal Exercise Chapter twenty-three 599

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