THE PHYSICIAN AND SPORTSMEDICINE - VOL 26 - NO. 4 - APRIL 98
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In Brief: Premenstrual syndrome, or PMS, typically involves physical symptoms like bloating, headache, and breast tenderness, along with psychological and behavioral changes like irritability, depression, and fatigue. Other conditions can mimic PMS, so it's important to rule out look-alikes such as contraceptive side effects, dysmenorrhea, and substance abuse. Moderate exercise and a healthy diet may alleviate symptoms for some patients. Others may require symptom-specific measures, hormonal therapy, psychotropic drugs, or, for recalcitrant cases, ovulation suppression.
Women of all athletic abilities can suffer from premenstrual syndrome (PMS), which in some cases can be debilitating. It is imperative that the primary care physician undertake a thorough, stepwise evaluation to rule out other conditions and know effective options for targeted treatment.
PMS is a combination of distressing physical, psychological, and behavioral changes during the luteal phase of the menstrual cycle. The core physical symptoms include bloating, headache, breast tenderness, and, less commonly, appetite changes, gastrointestinal upset, vasomotor flushing, heart palpitations, and dizziness. Psychological and behavioral changes often include irritability, depression, fatigue, labile mood, concentration difficulties, and forgetfulness. A physically active woman who has significant PMS symptoms may be less motivated to exercise or may show reduced athletic performance.
A key to diagnosis is that the symptoms occur during the luteal phase of the menstrual cycle (days 15 to 28). In addition, the appropriate diagnosis of PMS requires a combination of one psychological or behavioral change and one physical symptom consistently during the luteal phase (1). Because more than 150 behavioral, physical, and psychological symptoms are associated with PMS (2), widely accepted diagnostic criteria have been developed (table 1: not shown).
The appropriate diagnosis of PMS is vital for optimal outcome. Although many women come to the physician's office with individual symptoms of PMS, a systematic inquiry concerning signs and symptoms is crucial before treatment decisions can be made.
The first visit should focus on a careful history and physical examination to develop a complete differential diagnosis. The patient should receive instructions on how to chart her symptoms daily for her next two full menstrual cycles (figure 1: not shown). This usually entails tracking three to five of her most severe symptoms with daily recording of their absence or presence, severity, and menstrual timing. The first visit should also include other testing as needed to aid in the evaluation of other possible conditions in the differential. The patient should return after charting two complete cycles.
When evaluating the patient's symptom chart, it may prove useful to consider premenstrual, menstrual, and postmenstrual phases. Charting consistent with PMS will show symptoms at or after ovulation only, resolving within 4 days after the onset of menses. The follicular phase will be relatively symptom free.
Many patients who report PMS will have another condition that can account for their symptoms (table 2). Recording of symptoms will show that many patients experience no symptom-free interval or have non-menstrually related exacerbation of symptoms. These findings will divert the diagnosis away from PMS.
| Table 2. Conditions Commonly Confused With Premenstrual Syndrome Contraceptive side effects |
Hormonal contraceptive side effects, dysmenorrhea, eating disorders, substance abuse, and other medical conditions are commonly confused with PMS (3). Up to 60% of women seeking treatment for PMS have a diagnosed psychiatric disorder, with the most common being depression and adjustment disorders (4). Premenstrual worsening of psychiatric symptoms can make the diagnosis confusing, but PMS can be diagnosed only if the patient has an asymptomatic week during the follicular phase.
The Beck Depression Inventory may help in the diagnosis of depressive symptoms in PMS. Having the patient complete this test during the midfollicular and again in the late luteal phase helps distinguish those suffering from chronic depression from those who have PMS-associated depression.
The clinician must be aware of cyclic recurrence of other medical disorders, such as migraines, herpes, convulsive disorders, irritable bowel syndrome, and hypothyroidism, in which symptoms most often recur in the late luteal or early menstrual phase (5). A more complex pattern will be that of PMS with an additional disorder, which shows symptoms throughout the menstrual cycle but with different PMS symptoms in the late luteal phase. Non-PMS symptoms that are present in all three phases but more severe in a particular phase generally represent a cyclic exacerbation of a chronic disorder. Detailed charting and evaluation will help determine if such symptoms are consistent with PMS.
The first therapeutic options for PMS are typically self-help techniques like healthy nutrition, dietary supplements, increased exercise, and stress reduction. These measures should be emphasized if the patient's symptoms are not severe and last less than 1 week. Detailed discussions with the patient are vital for these nonpharmacologic options to succeed.
Diet and supplements. While no foods have been specifically shown to be beneficial in treating PMS, an overall healthy diet may reduce many symptoms.
Vitamin and mineral supplements have been suggested to ameliorate PMS symptoms. Calcium (1,000 mg elemental daily) and magnesium have been shown to improve mood and to reduce pain and fluid retention for patients experiencing PMS, though the mechanism of action is unknown (6,7). Extensive research has shown that vitamin B6, however, has inconsistent efficacy in PMS treatment, with possible neurotoxicity as a side effect (8). Calcium and magnesium are cofactors in neurotransmitter synthesis, which suggests a possible association between PMS symptoms and serotonin deficiency (5-8).
Exercise and other stress reducers. Besides improving cardiovascular status and general health, regular, moderate exercise appears to be the best nonpharmacologic agent to combat the symptoms of PMS (table 3) (9). Many anecdotal reports link exercise with a reduction or alleviation of PMS symptoms. Women who exercise seem to have fewer luteal-phase symptoms than sedentary individuals (9).
| Table 3. Potential Benefits of Moderate Aerobic Exercise for Women Who Have
Premenstrual Syndrome Fewer luteal-phase symptoms |
Aerobic activity decreases PMS symptoms more effectively than nonaerobic activity (10). Moderately intense aerobic activity seems to effect optimum reduction of symptoms. Good aerobic activities include walking, jogging, biking, swimming, rowing, and dancing.
Exercise has been found helpful in ameliorating mood alterations, without the untoward side effects of medications. Stress reduction seems to be the primary mode of action. Women who have a trained cardiovascular system have been found to have a more appropriate heart rate response to the stress of PMS than sedentary women (11,12). Studies (11,12) have shown that women who participate in regular exercise have decreased symptoms of impaired concentration, negative affect, behavior change, and pain. However, the positive effects of exercise on mood are reduced for those who train intensely (13).
Relaxation techniques have also been shown to reduce the mood symptoms of PMS (14). Relaxation techniques are particularly helpful for women who are able to identify their stressors.
Although no experimental evidence has shown that women who have PMS actually retain fluid, the sensation of bloating can often be treated. Reduction in dietary salt should be encouraged. If a diuretic is needed, spironolactone is the drug of choice because it is a potassium-sparing diuretic with less risk of inducing dependence than other diuretics (15). The physician must recommend diuretics cautiously; abuse can cause edema because decreased sodium stimulates the renin-angiotensin-aldosterone system to ultimately cause sodium retention. Patients should initiate diuretic use when the sensation of fluid retention begins and continue the drug until the onset of menses, when symptoms usually resolve.
Mastalgia can be conservatively treated with a support bra and reduced caffeine intake. For unresponsive, severe symptoms, nonsteroidal anti-inflammatory drugs (NSAIDs), bromocriptine mesylate, tamoxifen citrate, and danazol have all been shown to reduce breast pain (16-18).
Patients who experience insomnia, waking in the middle of the night, or daytime fatigue should try a regular sleep pattern and avoid physical activity and food just before bedtime, as well as alcohol. If needed, a tricyclic antidepressant taken 1 to 2 hours before bedtime may help (9).
Dysmenorrhea associated with PMS may be effectively treated with NSAIDs and/or oral contraceptives (OCPs). Physicians may need to try various NSAIDs until one relieves the patient's symptoms with tolerable side effects. If dysmenorrhea does not resolve with medical therapy, gynecologic consultation should be considered to evaluate for such problems as endometriosis, fibroid uterus, ovarian cyst, adenomyosis, and other pelvic disorders.
Migraines may be considered a symptom of PMS only if they occur in the late luteal or early menstrual phase and if other causes are ruled out. NSAIDs can be used as prophylactic or abortive therapy for patients experiencing monthly symptoms (19,20). If NSAIDs fail, beta-adrenergic blockers, such as propranolol hydrochloride in daily divided doses, or low-dose tricyclic antidepressants are often effective. Hormonal therapies that involve danazol or gonadotropin-releasing hormone (GNRH) agonists have also been suggested if first-line treatment proves ineffective (9).
If the most severe symptoms cannot be treated adequately with the therapies mentioned above, hormonal therapy should be considered. Treatment, however, must be individualized (19).
Younger women can be treated with oral contraceptives after consideration of dysmenorrhea and the need for contraception. With the exception of dysmenorrhea, however, oral contraceptive therapeutic effectiveness is controversial in PMS. The effect of oral contraceptives on PMS is very poorly defined in the literature, since few studies have specifically addressed this treatment, especially with the more current formulations. The studies that have been completed show very little if any effect on PMS symptoms with oral contraceptive use. Most PMS symptoms are not improved with oral contraceptives, and claims of their effectiveness in PMS should be questioned.
Perimenopausal women who have PMS symptoms and associated irregular menses should have their level of follicle-stimulating hormone measured to rule out menopause. Because treatment in this age-group will likely be short, it is often acceptable to go directly to ovulation suppression with daily medroxyprogesterone acetate. If menopause is diagnosed, standard combined estrogen-progestin hormone replacement therapy should be used.
PMS has never been proven to be associated with a progesterone deficiency, and many conflicting studies have been presented for the use of progesterone in the treatment of PMS (21). The use of natural progesterone has yielded a positive response for some clinicians (22). Some feel that the controversy over progesterone's efficacy is due to misunderstanding of the differences between natural progesterone and synthetic progestogens as well as a lack of adequate double-blind studies supporting the efficacy of natural progesterones (23,24). Thus, although the vast majority of literature does not support prescribing progesterone for PMS, the drug has its advocates.
For women who have PMS and significant mood lability, irritability, anxiety, or depression, psychotropic medications may be an option. Serotonin uptake inhibitors, such as fluoxetine hydrochloride and clomipramine hydrochloride, have been found to improve premenstrual psychological symptoms (25,26).
Naltrexone hydrochloride, a narcotic antagonist, and clonidine hydrochloride, a central alpha-2-adrenergic presynaptic autoreceptor agonist, have both shown improvement over placebo in treating premenstrual psychiatric symptoms (27-29). Their mechanism may be modulation of beta-endorphin levels. Alprazolam, a relatively new triazolobenzodiazepine, is a shorter-acting and potent anxiolytic that improves irritability, mood lability, anxiety, fatigue, and depression (30). Antidepressants, including nortriptyline hydrochloride, clomipramine, and fluoxetine, can help alleviate depressive symptoms associated with PMS (31-33).
Ovulation suppression is usually warranted only for cases refractory to one or more nonsuppressive therapies or for those that involve severe, disruptive symptoms. Methods of ovulation suppression may include oral medroxyprogesterone acetate, danazol (200 to 400 mg/day) (34), and GNRH agonists. Danazol and GNRH agonists appear to be the most effective of the hormonal suppressive therapies, but most patients are better served with GNRH agonists because of the bothersome androgenic side effects of danazol.
Oophorectomy is rarely indicated for PMS, and only after strict criteria are met (35). The patient's symptoms should have failed to resolve after all therapy except ovulation suppression by danazol or a GNRH agonist. The response to ovulation suppression must be the complete resolution of symptoms for a minimum of 4 to 6 months. If oophorectomy is solely for treating severe PMS, hysterectomy should also be performed. Otherwise, estrogen replacement therapy would also require the added risks and expense of cyclic progesterone to prevent endometrial carcinoma. With severe PMS, progestin therapy can create PMS-like symptoms and should be avoided.
Appropriate follow-up is just as important as treatment choice. Symptom recording, although exacting, must continue as part of treatment. If drug efficacy is established by symptom recording, such recording should continue at least every other cycle. If a decrease in effectiveness or any side effects are revealed, early adjustments can be made.
Because the first cycle or two may feature a placebo effect or a flare-up of symptoms unrelated to therapy, it's wise not to alter therapy because of one or two symptomatic cycles. If initial therapy proves effective over the first three cycles, the patient then can be re-evaluated less frequently, perhaps every 3 to 6 months.
Regardless of the effectiveness of treatment, if the patient initially had more severe symptoms--especially psychological ones--more frequent visits are warranted until the diagnosis is clearly established and effective treatment is instituted. Thus, individualized follow-up must be based on symptom profile, drugs prescribed, and the patient's requests.
Dr Ransom is an assistant professor and director of Community Programs and Health Effectiveness in the Department of Obstetrics and Gynecology at Wayne State University School of Medicine in Detroit and the Detroit Medical Center. He is a fellow of the American College of Obstetricians and Gynecologists and of the American College of Surgeons. Dr Moldenhauer is a resident in obstetrics and gynecology at Wayne State University and Hutzel Hospital in Detroit. Address correspondence to Scott Ransom, DO, MBA, Dept of Obstetrics and Gynecology, Wayne State University School of Medicine/Hutzel Hospital, 4707 St Antoine Blvd, Detroit, MI 48201.
THE PHYSICIAN AND SPORTSMEDICINE - VOL 24 - NO. 7 - JULY 96
In Brief: There's no better time than the years surrounding menopause for a woman to start or renew an exercise program. Exercise may reduce the immediate symptoms of menopause, and it decreases the long-term risk of cardiovascular disease, osteoporosis, and obesity. The exercise prescription includes aerobic exercise, resistance training, and stretching components, and should be individualized according to the woman's exercise history.
Menopause, which occurs at an average age of 52 years, is defined as a woman's final menstrual period. This event results from lack of endometrial stimulation by estrogen as the ovarian follicles become depleted. For 5 to 10 years preceding menopause and for 5 to 10 years following it, a woman is hormonally different from the way she was before and the way she will be after this climacteric interval.
Premenopausal women (prior to the climacteric or perimenopausal years) usually experience cyclic production of estrogen and progesterone, with high concentrations of estrogen prior to each ovulation and high concentrations of estrogen and progesterone during the luteal phase, after ovulation. Postmenopausal women (following the climacteric or perimenopausal years) usually have low levels of estrogen and progesterone, with little fluctuation and no cyclicity. Perimenopausal women commonly have fluctuating levels of estrogen that lack cyclicity and predictability.
Symptoms are common among perimenopausal and postmenopausal women. Some symptoms and problems are due to hormonal changes of the menopausal transition, while others result from the aging process and adverse lifestyle factors (eg, sedentary behavior, cigarette smoking, poor diet). It is often impossible to isolate these etiologic factors in evaluating and counseling individual women.
Specific types of exercise can be used to treat many problems experienced by menopausal women, and those who exercise regularly tend to report fewer menopausal symptoms and problems than sedentary women.
Vasomotor symptoms. The cause of vasomotor symptoms (hot flushes) is not yet known. However, these symptoms can be very uncomfortable and can lead to chronic sleep deprivation, as well as mood and behavior changes. Vasomotor symptoms are less common among physically active postmenopausal women than among sedentary controls (1), but exercise has not been shown to relieve such symptoms. Estrogen remains the most effective treatment for vasomotor symptoms.
Bone loss. Bone loss results from deficiencies of estrogen, exercise, and dietary calcium. The rate of bone loss in women accelerates at menopause because of the marked reduction in serum estrogen concentrations. (See "Guidelines for Diagnosing Osteoporosis" by Gail P. Dalsky, PhD)
It is preferable to prevent bone loss before it occurs, rather than to treat osteopenia or osteoporosis. Strategies for prevention of bone loss include hormone replacement therapy, calcium supplementation (unless dietary sources are adequate), and exercise. Both weight training and aerobic exercise enhance and maintain bone density. Postmenopausal women require 1,500 mg of calcium daily if they are not taking exogenous estrogen therapy and 1,000 mg of calcium daily if they are. Estrogen therapy prevents bone loss better than calcium supplementation or resistance exercise does; however, the combination of hormone replacement therapy and resistance exercise leads to a greater increase in bone density than does hormone replacement therapy alone (2), and it is likely that the combination of estrogen, calcium, and exercise is even more beneficial.
Cardiovascular disease. Cardiovascular disease risks rise with age among both sexes as a result of aging, other risk factors, and the cumulative effects of an adverse lifestyle. In women, cardiovascular disease risks rise sharply after menopause because estrogen deficiency induces lipid and vascular changes. Many of the adverse effects of aging and menopause on lipids (3) are reversed by aerobic exercise. Aerobic exercise promotes cardiovascular fitness and reduces risks of cardiovascular disease and cardiovascular mortality. Estrogen replacement therapy leads to a reduction in mortality from coronary heart disease and other causes (4).
Urogenital atrophy. Urogenital atrophy results from estrogen deficiency and is best treated with estrogen therapy, administered by any route. Exercise does not affect urogenital atrophy.
Depression and sleep disturbances. Some mood and sleep disturbances are related to estrogen deficiency; vasomotor symptoms can impair sleep and induce chronic sleep deprivation, which can cause mood disorders. Estrogen therapy improves sleep quality and enhances mood for many women with these symptoms. Regular aerobic exercise improves cognitive function, enhances mood, and promotes daytime alertness and nocturnal sleepiness. If mood and sleep disturbances are not relieved by estrogen therapy and/or exercise, antidepressant or other psychotropic medication should be prescribed, depending on the specific diagnosis.
Weight gain. Weight gain and accumulation of fat from aging and inactivity are common among perimenopausal and postmenopausal women. Aerobic and resistance exercise, which increase energy expenditure and lean-body mass, are the most effective ways to treat this problem.
Muscle weakness. Another common accompaniment of the aging process is loss of muscle tissue and strength. Many older women lack sufficient strength to remain functional and independent. Resistance exercise is the most effective way to increase and maintain muscle strength.
Hormone replacement therapy includes both estrogen and progestogen. Nearly all of the benefits result from estrogen alone. Progestational therapy should be added for endometrial protection in any woman who has a uterus but should not be prescribed for any woman who has had a hysterectomy.
Benefits. As described, estrogen therapy relieves vasomotor symptoms, prevents bone loss, reduces cardiovascular disease risk, relieves urogenital atrophy, and improves mood and sleep quality.
Contraindications and risks. In general, estrogen should not be prescribed for women who have breast or endometrial cancer, a history of thromboembolic disease, active hepatic dysfunction, or undiagnosed vaginal bleeding. Rare exceptions to these contraindications should be considered and managed on an individual basis. Relative contraindications include hormonally induced headaches and myomata uteri.
Hormone replacement therapy has not been associated with weight gain (5), despite nonscientific beliefs to the contrary. The major risk of hormone replacement therapy is the inconvenience of vaginal bleeding, which can often be minimized, eliminated, or regulated. If progestational therapy is adequate, the risk of endometrial cancer is less than in untreated women.
All women should be encouraged to exercise regularly, and older women often need instruction in specific, individualized programs. A plan that includes both aerobic and resistance training can help to prevent or relieve problems that are common among menopausal women, such as cardiovascular disease, obesity, muscle weakness, osteoporosis, depression, and sleep disturbances. It is the responsibility of physicians caring for these women to educate them appropriately and monitor their compliance (see "The Menopause Exercise Prescription," below).
Emphasizing the exercise component for women who are undergoing menopause can dramatically improve their quality of life. The short-term goal of exercise therapy is minimizing menopause symptoms, and the long-term goal is enabling women to remain independent and self-sufficient.
The Menopause Exercise PrescriptionThe most useful exercise prescription for older women includes aerobic, resistance, and stretching components. To maximize compliance, we must explain the rationale for the prescribed exercise in language that our patients can understand, and we must be sure our patients share our goals. Aerobic exercise--activities such as brisk walking, stationary bicycling, swimming, aerobics, or rowing--should be performed 7 days a week. The intensity will depend on the fitness of the woman, and the activity chosen depends on her interests, comfort, and convenience. Women who exercise regularly should work out for 20 to 60 minutes per session beginning and ending at a slightly slower pace to warm up and cool down. Previously sedentary women should begin by walking at a comfortable pace for 15 minutes, three times per week, gradually increasing time, frequency, and intensity. Resistance exercise should be performed two to three times each week, using free weights or machines. To maximize strength gains and to minimize the risk of injury, the patient should do the progressive resistance exercises with instruction and under supervision until she has mastered the techniques. Appropriate stretching exercises should be performed after each aerobic and resistance session to improve and maintain flexibility. These are best performed under supervision until the technique has been mastered. Healthy women can probably undertake such a program without medical screening. Those who have any medical problems or symptoms (eg, chest pain, dyspnea, syncope) should be evaluated thoroughly before beginning such a program. For most women, compliance requires a clear understanding of the benefits that may be gained through regular exercise. Prevention of obesity, osteoporosis, cardiovascular disease, and adult-onset diabetes is a sufficient incentive to keep most older women exercising, especially if the activities are enjoyable.M.S. |
Dr Shangold is director of the Center for Sports Gynecology and Women's Health in Philadelphia. She is a fellow of the American College of Sports Medicine and the American College of Obstetricians and Gynecologists. Address correspondence to Mona M. Shangold, MD, The Center for Sports Gynecology and Women's Health, 2 Franklin Town Blvd, Philadelphia, PA 19103.
Series Editor: Nicholas A. DiNubile, MD
THE PHYSICIAN AND SPORTSMEDICINE - VOL 26 - NO. 12 - DECEMBER 98
In Brief: Exercise may help control a number of physical and psychological problems and changes associated with menopause and midlife, including depression, weight gain, loss of muscle mass and bone density, the risk of coronary artery disease, and possibly vasomotor symptoms. The basic prescription of aerobic exercise (20 to 60 minutes 3 to 5 days per week) and strength training (2 to 3 days per week) should be adapted to the patient's medical condition, fitness level, motivation, experience, and preferences. Exercise effects can be supplemented by estrogen therapy, a low-fat diet, and adequate calcium and vitamin D intake.
Menopause and the surrounding years are times of change for women. (See "The Years Surrounding Menopause: Practical Terms for a Complex Time," below.) Hormonal alterations can produce symptoms such as hot flushes, night sweats, and vaginal dryness. General signs of aging, such as diminished strength and endurance, may become more pronounced and lead to reduced activity, increased weight, and depression. Serious health risks, such as cardiovascular disease and osteoporosis, may arouse concern.
Exercise--along with proper diet and, if advisable, hormone therapy--can help prevent or minimize many of the problems associated with menopause. Fortunately, midlife changes themselves may make women more aware of their health and more motivated to make positive lifestyle changes than they were when younger. Thus, the climacteric interval (the decade or so surrounding the cessation of menses, which occurs at an average age of 52 (1)) is an excellent time for physicians to talk to their patients about the benefits of exercise, encourage those who exercise to continue, and help those who don't exercise to begin. Positive changes at midlife can yield lasting benefits.
A number of physical and emotional manifestations have been associated with menopause, including depression, weight gain, irritability, insomnia, and loss of concentration. However, only two--vasomotor flushes and vaginal dryness--have been shown to be due to hormonal changes (2). Exercise does not seem to influence vaginal dryness, but it does have a demonstrated or at least possible influence on many of the other phenomena associated with menopause.
Vasomotor symptoms. There is some evidence that exercise reduces reports of hot flushes and night sweats, but it is not conclusive. A controlled, cross-sectional, population-based study (3) of over 1,600 women found that sedentary women were twice as likely to report hot flushes as physically active women. Another study (4) reported a drop in the incidence of hot flushes immediately following a 45-minute aerobic workout (but not subsequently), suggesting that exercise had only an acute effect. And two cross-sectional studies (4), involving 267 active and sedentary women, suggested that exercise-related reductions in reports of vasomotor symptoms may largely reflect the effect of exercise on mood. At present there is no evidence that exercise has a lasting or consistent effect on vasomotor symptoms.
Depression. Although depression and depressive signs are actually no more common at menopause than in any other period of a woman's life (5), many menopausal women report mood disturbances. These may be related to sleep deprivation caused by hot flushes and to neurotransmitter changes associated with aging (6). Regular aerobic exercise may be helpful, and many depressed people have treated themselves, often unknowingly, by exercising regularly.
Weight gain. Though many menopausal women report weight gain, objective studies (7) suggest that body mass index actually increases at a steady rate from the third through the seventh decades of life, with no acceleration in the perimenopausal period.
What appears to influence weight gain in middle age and after is not hormonal status, but a loss of muscle mass and the accompanying decline--1% to 2% per decade--in metabolic rate (8). Caloric restriction, the centerpiece of weight-loss efforts for most women, depresses metabolism still further, often leading to frustration and failure.
Exercise is particularly helpful for middle-aged women who want to control their weight because it reverses the diet-induced reduction in metabolic rate and also increases fat-free mass. In fact, physical activity of sufficient magnitude can largely offset age-related changes in body composition. A cross-sectional study (9) of female athletes and sedentary women, aged 18 to 69, found no difference in body fat percentage and fat-free mass between the youngest and oldest athletes. In addition, the resting metabolic rate of the older exercisers was closer to that of the young athletes than to that of sedentary, age-matched women.
Research has also shown that midlife women who increase their physical activity gain the least weight and subcutaneous fat. One study (10) followed 507 women, aged 42 to 50, for 3 years. Those who were least active at baseline and those whose activity declined during the study period gained the most weight.
Muscle mass. Maintaining muscle mass with exercise can also prevent the decline in strength that affects many women in menopause and beyond. Strength training is the most effective in this regard, and ample evidence shows that 8 to 12 weeks of progressive weight training can substantially increase muscle strength in women (as well as men) aged 50 and above, even into their 90s (11).
Bone loss. More ominous than the decline of muscle mass is the loss of bone in midlife. About 80% of the 25 million Americans who have osteoporosis are women. Women's vertebral and femoral bone loss begins after about age 30, and they lose about 0.5% to 1.0% of total bone mass annually from age 40 until menopause, when bone loss accelerates. During the first 5 to 10 years after menopause, annual bone loss averages about 2%. Thus, a woman can easily lose 15% to 30% of her peak bone mass by age 60 (12,13).
Estrogen deficiency appears to be the most important cause of this bone loss. Exercise is not a substitute for hormone replacement or other pharmacologic interventions when osteopenia is marked, but it plays an important role in preventing bone loss or increasing bone density (14,15). Indeed, athletic activity has been associated with bone hypertrophy of up to 40% (16).
In one controlled study (17) of 25 women aged 49 to 61, lumbar spine bone mineral density (BMD) was significantly higher in those who jogged or played volleyball than in those who had no regular physical activity. Walking has been shown to be beneficial as well. A 12-month study (18) of more than 200 postmenopausal women found that those who walked 7.5 miles per week had a higher average BMD of the trunk, legs, and whole body than those who walked less than 1 mile each week.
Although weight-bearing exercise is usually recommended for bone maintenance, any activity that stresses the bones or skeletal muscles appears to increase bone density. Swimmers, for example, have higher vertebral bone mineral content than age-matched sedentary persons (19). However, more recent studies indicate that nonimpact exercise is not as beneficial for bone density as medium-impact (walking) or high-impact activities (volleyball). Even though swimming is better than no exercise, it should probably be augmented with strength training to have a greater effect on BMD (20).
Coronary artery disease. The risk of coronary artery disease increases with age for both men and women, but it rises abruptly in postmenopausal women because of adverse lipid and vascular changes induced by estrogen deficiency. To some extent these changes can be reversed by aerobic exercise (21). A 3-year study (10) found that the high-density lipoprotein cholesterol level of healthy middle-aged women remained unchanged in those who increased their exercise over 3 years, while it fell in those who decreased their exercise.
Population studies have generally shown a strong inverse relationship between physical activity and heart disease risk and between cardiorespiratory fitness and risk of heart disease (22). While much of this research has focused on men, the findings are generally the same for women. For example, a study (23) of nearly 1,500 38- to 60-year-old Swedish women found that those who were inactive during leisure time had a nearly threefold greater incidence of coronary artery disease than those who were active.
An 8-year study (24) of more than 3,000 women showed that an increase in aerobic capacity resulted in a decrease in the risk of death from cardiovascular disease; those in the lowest quintile had nearly 10 times the risk of those in the highest quintile. Women can achieve a significant increase in aerobic capacity with a relatively modest exercise program, such as 30 minutes of running, walking, or cycling three times a week for 20 weeks (25).
A prescription for exercise should be given to virtually every woman at menopause--not to address specific symptoms of hormonal changes, but to initiate or reinforce patterns for general health maintenance. These patterns are important because women who are about 50 years old and inactive will lose muscle strength, bone density, and functional capacity at an accelerated pace as the effects of disuse are added to those of aging. The longer exercise is delayed, the more difficult it will be to begin.
Basic guidelines. The basic prescription should include aerobic and strength training. Ideally, a postmenopausal woman would do 20 or more minutes of aerobic exercise--brisk walking, stationary bicycling, swimming, or rowing--7 days a week. However, following the American College of Sports Medicine's (ACSM) guidelines (26) is certainly adequate: 20 to 60 continuous or accumulated minutes of aerobic exercise 3 to 5 days per week and strength training, using free weights or machines, 2 to 3 days per week. The ACSM also recommends flexibility training 2 to 3 days per week.
Individualizing the program. No single approach, however, is right for all women. When explaining the value of exercise, it's important to focus on the concerns of the individual. If a woman wants to reduce weight, emphasize that she can lose fat much more effectively through exercise than through dieting. If correcting abnormal lipids is the goal, exercise and diet are more effective than either alone (27). If fatigue is a concern, the patient may need to be reassured that a higher level of activity will boost rather than deplete energy and strength. Women who were brought up to equate inactivity with femininity--including many in their 50s and older--may need reassurance that exercise will not make them less feminine and will enhance their health and well-being.
A daily exercise schedule isn't for everyone. Many women who do not have concrete goals (such as weight loss) are likely to prefer three aerobic sessions per week, which is sufficient to improve cardiovascular fitness and maintain bone health. A woman who has been sedentary for years will need to start with an easy program--a comfortable 15-minute walk several times a week, for example.
Patients who are beginning a new exercise program should start slowly and increase the intensity and duration gradually. Those who are unfamiliar with strength training should have help in designing a workout and supervision in performing exercises correctly--a physician's or physical therapist's office is generally less intimidating than a crowded health club. Doing too much exercise or doing it incorrectly can cause musculoskeletal injuries that will disrupt progress. In training for health and fitness, it's better to err on the side of too little rather than too much.
Discuss the program with the patient to help her choose activities that are comfortable, pleasurable, and compatible with her lifestyle. Simple, practical suggestions--such as moving a stationary bicycle from the basement rec room to the living room--may substantially improve compliance.
A comprehensive approach to menopause demands more than exercise. Estrogen remains the best overall treatment for these patients: Hormone replacement therapy (HRT) will reduce the rate of bone loss and probably memory loss and the risk of heart disease, as well as improve sleep and relieve vasomotor symptoms. Although previous observational studies have shown that HRT reduces cardiovascular mortality rates even in women with pre-existing heart disease, a large, placebo-controlled, randomized 4-year investigation demonstrated that HRT does not prevent vascular events in women who already have heart disease (28).
Most women will benefit from HRT, although not all women need it. Women who have a uterus and are treated with estrogen therapy should also be treated with progesterone or a synthetic progestin to protect the endometrium (this is the only proven indication for progesterone currently accepted by the general scientific community). Although most women need both hormones, some need only estrogen or projesterone alone. Because of the complexity and uniqueness of each woman's hormonal status and therapeutic needs in midlife, decisions about HRT are probably best discussed with a woman's gynecologist or reproductive endocrinologist.
Exercise is not a substitute for estrogen therapy but an essential adjunct. All women in this age-group will benefit from regular exercise, and all physicians should be recommending it. It has been shown that the combination of resistance exercise and estrogen therapy leads to a greater improvement in bone density than either alone does (29). Exercise also appears to augment the effects of estrogen therapy and calcium supplementation, so diet modifications should be discussed when exercise is prescribed. Bone maintenance requires both physical activity and adequate daily intakes of calcium (1,500 mg for estrogen-deficient women or 1,000 mg for estrogen-replete women), which can come from dietary sources like dairy products or from supplements, and vitamin D (400 IU). A low-fat diet will further reduce cardiovascular risk.
Phytoestrogens. Eating a diet rich in phytoestrogens should be discouraged as a treatment for menopause. Some women who want to avoid HRT attempt to relieve hot flushes and other symptoms by consuming large quantities of foods--primarily soybean products--that contain estrogen-like compounds. The safety and efficacy of these foods, however, have not been studied sufficiently. The intake of phytoestrogens in such a regimen varies according to the food sources, and high concentrations may, in fact, be less safe than an approved pharmaceutical product, especially if progesterone is not provided for endometrial protection, as would routinely be done with HRT.
Women who intend to remain healthy, vital, and independent as they age need a well-rounded approach to health maintenance. Physicians who understand the effects of regular exercise on the physical and psychological problems of women in midlife and beyond can help them find the right balance of exercise, diet, and, if necessary, hormone therapy to achieve this goal.
The meaning of the term "menopause" is clear--it refers to a woman's final menstrual period. However, the hormonal dynamics of the time surrounding menopause are complex, and the language used to describe this time is confusing.
Women between the ages of 40 and 60 are gynecologically very heterogeneous. Some are still ovulating and menstruating regularly and producing normal quantities of estrogen and progesterone. Others may bleed regularly or irregularly but have consistent or sporadic deficiencies of estrogen and/or progesterone. The remainder have ceased menstruating completely and have deficiencies of both estrogen and progesterone.
Further, in a study (1) of hormonal dynamics in the few years immediately preceding menopause, the authors showed that serum estrogen concentrations and urinary estrogen excretion tend to be higher than before or after these years, and progesterone concentrations and urinary progesterone excretion tend to be lower. While these findings may be very important in the development of gynecologic disorders (uterine myomata and abnormal bleeding, for example), their relationship to other aspects of midlife health, such as cardiovascular disease and bone loss, remains unclear. (The complex endocrinology of the perimenopause is beyond the scope of this article, but more information is available in a comprehensive and eloquent review (2).)
The World Health Organization (WHO) has recommended (3) the use of the term "perimenopause" to refer to "the period immediately before the menopause (when the endocrinological, biological, and clinical features of approaching menopause commence) and the first year after menopause." The WHO defines "menopausal transition" as "only the portion of the perimenopause before the final menstrual period."
These definitions, however, are impractical because they can be applied only in retrospect. A woman does not know that a menstrual period is her last until she fails to have another. An entire year must pass before she can be considered definitely postmenopausal.
Given this impracticality and the complex ovarian hormonal changes and gynecologic heterogeneity of 40- to 60-year-old women, "perimenopause" and "menopausal transition" are not used in the accompanying article. Instead "midlife" and "climacteric" are used interchangeably to refer to years immediately before and after menopause, in most cases covering the age range from about 40 to 60 years.
Dr Shangold is director of The Center for Women's Health and Sports Gynecology in Philadelphia. She is a fellow of the American College of Sports Medicine and the American College of Obstetricians and Gynecologists. Mr Sherman is a freelance writer in New York City. Dr DiNubile is an orthopedic surgeon in private practice in Havertown, Pennsylvania, specializing in sports medicine and arthroscopy. He is the director of Sports Medicine and Wellness at the Crozer-Keystone Healthplex in Springfield, Pennsylvania; a clinical assistant professor in the department of orthopedic surgery at the University of Pennsylvania in Philadelphia; the orthopedic consultant to the Philadelphia 76ers basketball team and the Pennsylvania Ballet; and a member of the editorial board of The Physician and Sportsmedicine. Address correspondence to Mona M. Shangold, MD, 1601 Walnut St, Ste 1200, Philadelphia, PA 19102.