Daily physical activity and hot flashes in the Study of Women's Health Across the Nation (SWAN) Flashes Study

Acute increases in physical activity and temperature are associated with hot flash experience in midlife women

OBJECTIVE

This study determined the association between acute changes in physical activity, temperature, and humidity and 24-hour subjective and objective hot flash experience.

METHODS

Data collection occurred during the cooler months of the year in Western Massachusetts (October-April). Women aged 45-55 across three menopause stages (n = 270) were instrumented with ambulatory monitors to continuously measure hot flashes, physical activity, temperature, and humidity for 24 hours. Objective hot flashes were assessed via sternal skin conductance, and subjective hot flashes were recorded by pressing an event marker and data logging. Physical activity was measured with wrist-worn accelerometers and used to define sleep and wake periods. Logistic multilevel modeling was used to examine the differences in physical activity, humidity, and temperature in the 10 minutes preceding a hot flash versus control windows when no hot flashes occurred. The odds of hot flashes were considered separately for objective and subjective hot flashes as well as for wake and sleep periods.

RESULTS

Data from 188 participants were included in the analyses. There was a significantly greater odds of a hot flash following acute increases in physical activity for objective waking hot flashes (odds ratio [OR], 1.31; 95% confidence interval [CI], 1.17-1.47; P < 0.001) and subjective waking hot flashes (OR, 1.16; 95% CI, 1.0-1.33; P = 0.03). Acute increases in the actigraphy signal were associated with significantly higher odds of having an objective (OR, 1.17; 95% CI, 1.03-1.35; P < 0.01) or subjective (OR, 1.72; 95% CI, 1.52-2.01; P < 0.001) sleeping hot flash. Increases in temperature were significantly related to the odds of subjective sleeping hot flashes only (OR, 1.38; 95% CI, 1.15-1.62; P < 0.001). There was no evidence for a relationship between humidity and odds of experiencing any hot flashes.

CONCLUSION

These results indicate that acute increases in physical activity increase the odds of hot flashes that are objectively measured and subjectively reported during waking and sleeping periods. Temperature increases were only related to subjectively reported nighttime hot flashes.

Weight Gain in Midlife Women

PURPOSE OF REVIEW

To summarize the evidence and clinical implications of weight and body composition changes during midlife in women and provide an overview of weight gain prevention and management in this population.

RECENT FINDINGS

Aging-related changes such as decreased energy expenditure and physical activity are important culprits for weight gain in midlife women. The hormonal changes of menopause also influence body adiposity distribution and increase central adiposity. These body changes can have health consequences including the development of cardiometabolic diseases, osteoarthritis, cancer, worsening in cognition, mental health, and menopause symptoms. Midlife women experience changes related to aging, menopause, and lifestyle which favor weight gain. Clinical practice should focus on early counseling and anticipatory guidance on the importance of dietary changes and physical activity to attenuate this phenomenon. Future research should focus on the longitudinal relationship between weight trends in midlife and health consequences and mortality.

The influence of habitual physical activity and sedentary behavior on objective and subjective hot flashes at midlife

OBJECTIVE

The purpose of this study was to evaluate relationships between physical activity, sedentary time, and hot flashes during both waking and sleeping periods using concurrent objective and subjective measures of hot flashes in midlife women.

METHODS

Women aged 45 to 55 years (n = 196) provided self-reported data on physical activity and underwent 24 hours of hot flash monitoring using sternal skin conductance. Participants used event marking and logs to indicate when hot flashes were perceived. Wake and sleep periods were defined by actigraphy. Mean ambient temperature and humidity were recorded during the study period. Generalized linear regression modeling was used to evaluate the effect of physical activity types and sedentary time on hot flash outcomes. Isotemporal substitution modeling was used to study the effect of replacing sedentary time with activity variables on hot flash frequency.

RESULTS

Modeled results indicated that increasing sitting by 1 hour was associated with a 7% increase in the rate of objectively measured but not subjectively reported hot flashes during sleep. Replacing 1 hour of sitting with 1 hour of vigorous activity was associated with a 100% increase in subjectively reported but not objectively measured waking hot flashes. There was little evidence for an effect of temperature or humidity on any hot flash outcome.

CONCLUSIONS

These data provide support for relations between sedentary time, physical activity, and hot flashes and highlight the importance of using objective and subjective assessments to better understand the 24-hour hot flash experience.

Physical activity and exercise for hot flashes: trigger or treatment?

IMPORTANCE AND OBJECTIVE

Hot flashes (HFs) are a prevalent feature of menopause. Hot flashes can be bothersome and affect quality of life. However, HFs have also been associated with the risk for cardiovascular disease. Therefore, providing current evidence on the effect of therapies to reduce HFs can help patients and providers with decision making. This review provides details on the scientific evidence to date related to the effect of physical activity (PA) and exercise to alter the HF experience in women.

METHODS

The PubMed database was searched between June 2020 and June 2022 for currently available evidence regarding the relation between PA and exercise and HFs. Our analysis included randomized control trials on exercise training, epidemiological studies, and studies evaluating acute exercise on the self-reported and objectively measured HF experience in addition to systematic reviews on the topic published as of June 2022.

DISCUSSION AND CONCLUSIONS

The majority of evidence from randomized control trials indicates that aerobic and resistance exercise training lead to a decrease in subjectively experienced HFs. The limited available studies on acute exercise indicate that a bout of moderate-intensity exercise may decrease objectively measured and self-reported HFs but acute increases in PA intensity above accustomed levels may influence subjective HF experience. Some evidence suggests that for those with depression, habitual PA may be an effective way to reduce HF symptoms. Weighing the available evidence, for people who experience HFs, engaging in regular moderate-intensity PA, including aerobic and resistance exercise, may be an effective therapy to reduce HFs and women should be counseled on the benefits of regular, moderate exercise. However, significant gaps in knowledge remain about the optimal exercise prescription, effectiveness for a diverse population, meaning of differences between objective and subjective experience, and mechanisms that lead to changes in HFs.

Association between physical activity, cardiorespiratory fitness, and body composition with menopausal symptoms in early postmenopausal women

OBJECTIVE

The aim of this study was to investigate the relationship between daily physical activity (daily activities, exercise, and sitting time), cardiorespiratory fitness (CRF), and body composition (body mass index [BMI], waist to hip ratio [WHR)] with menopausal symptoms and to determine the strongest predictor(s) of menopausal symptoms.

METHODS

The Menopause Rating Scale questionnaire was used to examine somatic, psychological, urogenital, and total symptoms of menopause. The energy expenditure of daily physical activity, exercise, and sitting time was measured by the International Physical Activity Questionnaire, and CRF was measured by estimating the maximal oxygen intake (VO2max) through the Rockport test. Statistical methods of the Pearson correlation coefficient and hierarchical multiple linear regression were used for data analysis.

RESULTS

Fifty-six women, aged 50 to 65 years, voluntarily participated in the study. Exercise energy expenditure was inversely correlated with total (r = -0.403, P = 0.002), somatic (r = -0.293, P = 0.023), and urogenital (r = -0.343, P = 0.009) symptoms of menopause. VO2max was inversely correlated with urogenital symptoms of menopause (r = -0.414, P = 0.002). WHR was positively correlated with somatic symptoms of menopause (r = 0.286, P = 0.032); sitting was correlated with total (r = 0.40, P = 0.002), somatic (r = 0.325, P = 0.015), and psychological (r = 0.274, P = 0.015) symptoms of menopause. Among the study variables, sitting (β=0.365, P = 0.004) and VO2max (β=-0.286, P = 0.030) were the most important predictors of total symptoms of menopause; sitting was the predictor of somatic symptoms (β=0.265, P = 0.045), and VO2max was the predictor of urogenital symptoms of menopause (β=-0.332, P = 0.014). The inclusion of age, BMI, WHR, and duration of menopause as confounding variables in regression analysis did not change the findings related to the predictions of menopausal symptoms.

CONCLUSION

Reducing sitting time, improving VO2max, decreasing WHR, and exercise can be recommended by priority to alleviate menopausal symptoms. Considering the small number of participants in this investigation, future studies are, however, recommended.

Physical Activity and Physical Function: Moving and Aging

Evidence supports that the physical disablement process starts earlier than previously thought, in midlife when women still have many years to live. Physical activity participation and interventions have been successful in preventing disability in older adults and may be promising for maintaining function at younger ages. Changing the conversation to more relevant topics in midlife, like positive changes in body composition, sleep, and improved mood, may move the dial on participation, as midlife women do not meet guidelines for physical activity. Exploring the role of reproductive aging beyond chronologic aging may provide gender-specific insights on both disablement and participation.

Recent evidence exploring the associations between physical activity and menopausal symptoms in midlife women: perceived risks and possible health benefits

Although the health benefits of physical activity are well established, the prevalence of midlife women accumulating sufficient physical activity to meet current physical activity guidelines is strikingly low, as shown in United States (U.S.) based surveillance systems that utilize either (or both) participant-reported and device-based (i.e., accelerometers) measures of activity. For midlife women, these low prevalence estimates may be due, in part, to a general lack of time given more pressing work commitments and family obligations. Further, the benefits or "reward" of allocating limited time to physical activity may be perceived, by some, as too distant for immediate action or attention. However, shifting the health promotion message from the long term benefits of physical activity to the more short-term, acute benefits may encourage midlife women to engage in more regular physical activity. In this article, we review the latest evidence (i.e., past 5 years) regarding the impact of physical activity on menopausal symptoms. Recent studies provide strong support for the absence of an effect of physical activity on vasomotor symptoms; evidence is still inconclusive regarding the role of physical activity on urogenital symptoms (vaginal dryness, urinary incontinence) and sleep, but consistently suggestive of a positive impact on mood and weight control. To further advance this field, we also propose additional considerations and future research directions.