Women’s Health Research Update

Research on women’s health is surging with medical developments and new study findings on exercise benefits,
cardiovascular disease, fat metabolism, exercise behaviors, hypertension, metabolic syndrome, musculoskeletal problems and longevity. Our vocation, as fitness professionals, requires us to combine modern-day science with newer, safer and more effective forms of exercise. Although many consumers seek out the guidance of “medicine makers,” it is becoming more apparent from the research that fitness professionals play an important role in guiding clients to sensible solutions for their health. How can you best help women? The following studies produced findings that you can immediately use to impact your female clients in positive ways.

Turner, M.B., Vader, A.M., & Walters, S.T. 2008. An analysis of cardiovascular health information in popular young women’s magazines: What messages are women receiving? American Journal of Health Promotion, 22 (3), 183–86.

Cardiovascular disease (CVD) is the number-one killer of women in the United States, with more than 450,000 deaths each year (American Heart Association [AHA] 2009). Nearly 39% of all female deaths in the nation occur from CVD, which includes coronary heart disease (CHD), stroke and other cardiovascular diseases (AHA 2009a). According to the AHA, the majority of women are unaware of this serious threat to their health.

What behavior can help protect against CVD? Low- to moderate-intensity exercise (e.g., walking, yard work, dancing and gardening) for up to 30 minutes daily will help combat the onset of this disease. More vigorous aerobic activities (e.g., swimming, bicycling, roller skating and running) add even greater cardiovascular health benefits. In addition, nutrient-rich foods—such as vegetables, fruits, whole-grain products and low-fat (or fat-free) dairy products—contain vitamins, minerals, fiber and other nutrients for a healthy diet, optimal weight management and CVD prevention. While exercise and healthy eating can help, smoking hurts. Cigarette smokers are two to three times more likely to die of heart disease (AHA 2009b).

Women need to know this information so they can make informed decisions about their lifestyle habits. Are they getting it by reading magazines? Turner and colleagues assessed whether the cardiovascular health information in six issues (spanning 6 months) of four popular women’s magazines (Cosmopolitan, Glamour, Vogue and Shape) was consistent with the AHA guidelines for physical activity, nutrition, weight management and smoking. The authors report that these magazines represent 10 million readers, the majority of whom are aged 18–34 years. The most common cardiovascular health topic covered in these magazines was physical activity, followed by nutrition, weight management and cigarette smoking. The subject area in which content was most consistent with AHA guidelines was nutrition (78%), followed by smoking (68%), physical activity (66%) and weight management (19%). The researchers note that weight management content had a low association with AHA guidelines because the articles reviewed lacked specific information on weight management and CVD (i.e., information on body mass index [BMI] and waist circumference assessment, etc.). The
authors acknowledge that a limitation of this 6-month analysis of these magazines is that it may not adequately depict a full year of article content.

Take-Away Message: It appears that some of the popular young women’s magazines are providing truthful and helpful content in regard to cardiovascular health information, but more specific information about weight management and its association to CVD is recommended.

Coylewright, M., Reckelhoff, J.F., & Ouyang, P. 2008. Menopause and hypertension: An age-old debate. Hypertension, 51 (4), 952–59.

Hypertension is an elevation in arterial blood pressure equal to or exceeding a systolic blood pressure of 140 millimeters of mercury (mm Hg) and/or a diastolic blood pressure of 90 mm Hg (ACSM 2006). Prehypertension is the classification when systolic blood pressure is 120–139 mm Hg and/or diastolic blood pressure is 80–89 mm Hg (ACSM 2006). The risk of many diseases (e.g., stroke, congestive heart failure, kidney failure and peripheral vascular disease) increases with the prevalence of hypertension. Most women will develop hypertension during their lifetime.

Coylewright and colleagues report that women who develop hypertension at a younger age are at higher risk of adverse cardiovascular events. According to these researchers, several studies propose that the onset of hypertension in women coincides with the beginning of menopause, while conflicting research suggests that the condition is more related to age. In their review, the researchers propose that this conflicting research-based evidence is most likely due to numerous methodological differences in research design among the published studies.

Several factors may contribute to hypertension in postmenopausal women:

• Estrogen deficiency may lead to dysfunction of the
  endothelium (layer of cells that line the interior surface
  of blood vessels) thus reducing the effectiveness of the
  vasodilators (chemicals that relax the smooth muscle in blood vessels) that modulate blood vessel vascular tone (muscle tone of the walls within blood vessels).
• Increased artery stiffness appears to coincide with menopause.
• The hormone estradiol seems to provide cardioprotection by controlling mechanisms of the renin-angiotensin system (which is a regulator of blood pressure, blood fluids and electrolytes). Unfortunately, this cardioprotection is lessened when women hit menopause and estradiol levels decrease.
• Postmenopausal women are more salt-sensitive than premenopausal women.
• The onset of obesity, which occurs with some women during menopause, has a strong correlation to hypertension.

If your female clients do develop hypertension, how can exercise help? ACSM (2006) recommends that aerobic activities performed at 40%–70% of heart rate reserve be the primary exercise mode for people with hypertension. The frequency should be 3–7 days per week. Daily exercise may be the most beneficial option for controlling hypertension, owing to the positive acute effects of aerobic exercise in lowering blood pressure (in hypertensives) for several hours after the activity. Exercise duration should be 30–60 minutes. Resistance exercise (lower resistances with higher repetitions) is not recommended as the primary form of exercise, but it should be combined with aerobic training.

Take-Away Message: In women, the association of hypertension with menopause is a multifactorial phenomenon, with many factors proposed and many questions still unanswered. However, participation in regular aerobic exercise is a critically important lifestyle modification that has been shown to lower systolic (-7.4 mm Hg) and diastolic (-5.8 mm Hg) blood pressure in people with hypertension (ACSM 2006).

Friedenreich, C.M., & Cust, A.E. 2008. Physical activity and breast cancer risk: Impact of timing, type and dose of activity and population subgroup effects. British Journal of Sports Medicine, 42, 636–47.

Breast cancer is the most common malignancy among women in the United States, accounting for 26% of all cancer cases and a total of 182,460 new cases in 2008 (American Cancer Society 2009). Lung and bronchus cancer (14%) are second, followed by colon and rectum cancer (10%). The American Cancer Society advises that adopting certain lifestyle behaviors can lower
a woman’s risk of developing breast cancer. Guidelines include reducing alcohol use, engaging in physical activity, maintaining a healthy weight, eating a balanced diet (with at least five servings of fruits and vegetables a day) and breast-feeding (when
applicable). Friedenreich and Cust’s research review describes how well over 80 studies now convincingly suggest that there is an inverse relation between physical activity and breast cancer; in other words, exercise reduces the risk of breast cancer.

In this recent review the authors found that breast cancer risk was approximately 25% lower for the most physically active women than it was for the least active females. Moderate and vigorous exercise yielded nearly equal benefits vis-à-vis breast cancer risk. Being physically active throughout life conferred the highest risk-prevention benefits. The authors note that physical activity reduced the risk of breast cancer in all groups of females except obese women (as determined by BMI ≥ 30 kg/m² [weight in kilograms/height in meters squared]). The greatest risk reduction was in lean females with a BMI of < 22 kg/m². The authors summarize that the positive influence of physical activity on cancer risk may be due to a modulation of inflammation and immune function. It appears that exercise may favorably change the balance of pro- and anti-inflammatory cytokines (signaling molecules, which—like hormones and neurotransmitters—are used extensively in cellular communication), thus lessening the negative effects of chronic inflammation in the circulatory system.

Take-Away Message: The evidence is extremely persuasive that moderate to vigorous exercise reduces the risk of breast cancer. Regular exercise throughout life reduces the risk even further. These risk reductions are more noticeable in nonobese populations.

Tarnopolsky, M.A. 2008. Sex differences in exercise metabolism and the role of 17-beta estradiol. Medicine & Science in Sports & Exercise, 40 (4), 648–54.

It has generally been assumed that men and women have similar muscle fiber types and thus metabolize fats, carbohydrates and proteins in similar ways. Indeed, the majority of the studies on metabolism have been done with male populations, assuming this similarity.

Tarnopolsky reviewed studies in which fat, carbohydrate and protein were broken down during endurance exercise (> 60 minutes). His finding? Compared with men, women burn more fat and less carbohydrate during endurance activities. This elevated use of fat is also seen in women before and after training, suggesting that the underlying mechanism is due to a sex difference between men and women, and not a training effect. Tarnopolsky also notes that women have been shown to have a slightly higher percent of type I—or slow-twitch (oxidative)—muscle fibers, which may partially contribute to the increased fat metabolism during endurance-type activities. More profoundly, it appears that a major estrogen—17-beta estradiol—is the mediating hormone that enhances fat oxidation pathways in women (thus sparing carbohydrates) during endurance exercise. (Men also have 17-beta estradiol in the body, but in low levels.)

Take-Away Message: If your female clients wish to optimize fat metabolism through exercise, encourage them to include some endurance exercise bouts (> 60 minutes) in their cardiovascular training.

Cotter, K.A., & Sherman, A.M. 2008. Love hurts: The influence of social relations on exercise self-efficacy for older adults with osteoarthritis. Journal of Aging and Physical Activity, 16, 465–83.

A key benefit of exercise for older adults is the decrease in musculoskeletal pain and improvement in joint mobility and function, especially for people with osteoarthritis. One of the most effective strategies for promoting regular exercise is positive self-efficacy. A person has self-efficacy when he believes he is capable of performing in a certain way that will lead to the attainment of specific goals. To use self-efficacy as a teaching aid, you can help clients attain competence in regular exercise programs and educate them that this activity will lead to a healthier, more active lifestyle. Eventually clients will internalize this belief themselves, further encouraging this optimistic outcome.

Cotter and Sherman report that research promoting exercise self-efficacy has been shown to improve exercise adherence in older adults because it instills a sense of self-confidence in the ability to be regularly active. However, many older individuals may experience what is referred to as “social strain”—negative feedback from other people who try to dissuade them from
exercising. Statements like “You are always exercising and never have time to be with me” provide social strain, which may stifle a person’s motivation to keep exercising. Cotter and Sherman’s recent study involving older adults (77% women) with
osteoarthritis found that social support was a positive predictor of exercise self-efficacy. However, they also found that many older women were distracted by social-strain influences that
endangered exercise self-efficacy.

Take-Away Message: Understand how clients’ present and future success with exercise adherence can be influenced by social strain, and be on the alert for it. Help clients realize early on that others may find your clients’ dedication to a healthy lifestyle a distraction or detour from a relationship. Advise clients to address these issues with their significant others and seek their support. Ideally friends and family will learn to play a constructive role in your clients’ long-term exercise adherence. See the research on women’s exercise behaviors later in this article (“How Can We Get More Women Exercising?”) for more extensive findings related to this topic.

Irving, B.A., et al. 2008. Effect of exercise training intensity on abdominal visceral fat and body composition. Medicine & Science in Sports & Exercise, 40 (11), 1863–72.

Metabolic syndrome is a cluster of CVD risk factors that are associated with elevated blood triglycerides, hypertension and insulin resistance. Having three or more risk factors is the criterion for metabolic syndrome. See the sidebar “Risk Factors for Metabolic Syndrome” for details.

Central obesity, measured by waist circumference, is a risk factor for metabolic syndrome. The good news is that cardiovascular exercise has been shown to be an effective strategy for decreasing visceral abdominal fat. However, there is no widespread consensus as to what dose of exercise will achieve the most healthful effect.

In this 16-week study by Irving and colleagues, researchers looked at 27 moderately obese (BMI = 34 ± 6 kg/m²), sedentary (reporting an exercise frequency of less than 2 days per week), middle-aged (51 ± 9 years of age) women with metabolic syndrome. Subjects were randomly assigned to one of three different 16-week interventions:

1. Seven subjects maintained their current level of activity (< 2 days per week) or inactivity, thus serving as the control group.
2. Eleven subjects exercised 5 days per week at an intensity ≤ lactate threshold (the point in exercise where lactate accumulates in a nonlinear manner, which is approximately an RPE of 10–12), expending 400 kilocalories each session.
3. Nine subjects exercised 3 days per week at an intensity lactate threshold (RPE 15–17) and 2 days per week at an
   intensity ≤ lactate threshold (RPE 10–12), equaling 400 kilocalories per session.

Groups 2 and 3 both did walk/run exercise programs that
totaled 2,000 kilocalories per week. No subjects altered their diet during the study.

The results? Only the high-intensity exercise group (group 3) significantly decreased body weight, BMI, percent body fat, fat mass and waist circumference. This group also showed an increase in high-density lipoprotein cholesterol (the healthy cholesterol) and a decrease in triglycerides. Although the kilocalorie expenditure was matched for the two exercise groups, the researchers suggest that postexercise oxygen consumption (exercise afterburn) was likely greater in the high-intensity group, as this has been commonly shown in previous research.

Take-Away Message: This study adds to the increasing number of investigations suggesting that female clients who want to obtain optimal health benefits and reduce risk factors for metabolic syndrome should follow a training program of progressively increasing intensity. Initially, and very importantly, get clients regularly exercising and being physically active on most, if not all, days of the week (expending around 2,000 kilocalories per week). Then, progressively provide the exercise direction for them to get “fitter” with gradual increases in exercise intensity in their cardiovascular workouts.

Vrazel, J., Saunders, R.P., & Wilcox, S. 2008. An overview and proposed framework of social-environmental influences on physical-activity behavior of women. American Journal of Health Promotion, 23 (1), 2–12.

For women, the health benefits of exercising include reduced risk of type 2 diabetes, coronary heart disease, stroke, some cancers and other leading causes of disability. Mortality rates are much lower among physically active women compared with their inactive counterparts. However, Vrazel and colleagues note that despite the meaningful health benefits of exercise, females are regularly shown to be less active than males, and physical activity levels decrease considerably as women age. Understanding and changing the causes of this inactivity is of great concern to fitness professionals and researchers, and was the motivation of this research review.

In their attempt to identify and understand the factors affecting women’s exercise behaviors, the authors centered their investigation on the impact of the social environment, which has been a focus of current research. Researchers began by making an exhaustive search of several databases of studies, both quantitative and qualitative, involving women 20–60 years of age. For
the purposes of the search, physical activity was defined as any bodily movement resulting in energy expenditure, including lifestyle activity, leisure-time activity and exercise. Forty-three studies met all of the researchers’ criteria for inclusion in the research review. Although a complex group of factors exist in the social environment that influence women’s exercise behaviors, two major areas discussed in this article were social support and cultural standards.

SOCIAL SUPPORT

Social support is the most understood and investigated area of a woman’s social environment. This type of assistance can consist of emotional, informational, instrumental or appraisal support.

Emotional Support. Emotional support is present when a woman feels acceptance from other people. This support involves daily-life connections with others, such as colleagues at work, personal friends and family members. There is pervasive research evidence that women want this kind of support and encouragement to be physically active. Investigations reveal that women who receive support from their friends and family are much more likely to be consistently physically active. Women who are strongly assured by others of the worthiness of exercise are also more likely to sustain an exercise program. Fitness professionals are incredibly important providers of emotional support for the female exerciser. The data additionally illustrates that having a workout partner, companion(s) or group to exercise with is a big facilitator of exercise adherence in women.

Information Support. Information support involves getting fitness- or health-related input, as provided by magazines, television and the Internet. This type of support is most useful to women if it includes specifics on health benefits (e.g., the benefit of exercise in reducing cancer risk) and strategies for fitting exercise into a busy life. You can help provide and guide clients with informational support.

Instrumental Support. Instrumental support is a tangible service, some type of specific aid; for example, assistance with the multiple tasks of daily life. A woman may have someone to help with household duties, someone who can lend a hand with caregiving for the family or a personal trainer to guide her exercise program. If her significant other is willing to take on some of the responsibilities of raising children, it is more likely she will be willing and able to make time for exercise.

Appraisal Support. Appraisal support involves constructive feedback and affirmations that help develop beliefs about exercise. Hearing from a medical correspondent that exercise is good for you can be a catalyst to begin and/or continue exercise. Thus, appraisal support helps develop core values about the worthiness of fitness.

CULTURAL STANDARDS

Gender-role expectations are included in cultural standards and are a complex aspect of a woman’s social environment. For example, many women feel social pressure to make family obligations their primary focal point and to concentrate their efforts on these obligations above personal interests, such as exercise. Another chief issue with cultural standards is whether or not exercise is accepted as culturally appropriate. Research suggests that women perceive acceptance of exercise as an essential factor in persuading them to exercise. With some subpopulations of women, such as Hispanic females, having the husband’s “consent” is crucial for a woman to participate in an exercise program.

Of special interest to fitness professionals is the research finding that females actively seek role models to inspire and motivate them to be active. This finding explains how celebrity fitness gurus often garner so much attention. However, the research suggests that women need more role models in their communities—personal trainers are perfect examples—who can show them how they can lead their life, go to work, care for the family and still be physically active.

Take-Away Message: This study unmistakably provides evidence-based research showing that a woman’s social environment is critically important to her physical activity behavior. Most striking from this research is the discovery of how important it is for fitness professionals to serve their clients as role models.

Women enjoy having options for healthy choices. The challenge is that when they have dozens of options, but no single choice that truly works for all women, they get frustrated. That’s why your assistance and education are key. The newest research suggests that your role is paramount to the exercise success of women. Embrace your role and “be the example” through your own daily life as you lead your clients to healthy lifelong solutions.