Objectively determined physical activity and adiposity measures in adult women: A systematic review and meta-analysis

The prevalence of adiposity is increasing among adult women. Although emerging evidence suggest that all patterns of heightened physical activity (PA) are important to benefit adiposity, the relationship between objectively assessed intensities of PA and adiposity in women has not yet been assessed. Therefore, this systematic review and meta-analysis aims to qualitatively synthesize and quantitatively assess the evidence for any relationship between objectively measured PA and a wide range of adiposity indicators to guide PA prescription in adult women. Four databases (PubMed, Web of Science, Scopus, and the Cochrane library) were searched for eligible studies. 35 studies were included (25 observational and 10 interventional studies), with a total of 9,176 women from 20 countries included. The overall pooled correlation for random effects model (n = 1 intervention and n = 15 cross-sectional studies) revealed that the total volume of physical activity (TPA) was moderately associated with percentage body fat (%BF) (r = −0.59; 95% CI: −1.11, −0.24; p = 0.003). There was a weak but significant association between MVPA with body mass index (BMI), waist circumference (WC), and visceral adiposity. Daily steps were significantly associated with BMI, %BF, WC, and fat mass, with the strongest association with %BF (r = −0.41; 95% CI: −0.66, −0.19; p < 0.001). Walking programs resulting in increasing daily steps only had a significant effect on WC (SMD = −0.35; 95% CI: −0.65, −0.05; p = 0.02). Overall, objectively determined PA in terms of steps, TPA and MVPA were favorably associated with adiposity outcomes. The improvement in adiposity can be achieved by simply accumulating more PA than previously and adiposity is more likely to be benefited by PA performed at higher intensity. Nonetheless, these results should be interpreted with caution as there were a small number of studies included in the meta-analysis and the majority of studies included utilized cross-sectional designs.

Associations between Objectively Determined Physical Activity and Cardiometabolic Health in Adult Women: A Systematic Review and Meta-Analysis

The purpose of this systematic review and meta-analysis was to qualitatively synthesize and quantitatively assess the evidence of the relationship between objectively determined volumes of physical activity (PA) and cardiometabolic health in women. Four databases (PubMed, Web of Science, Scopus, and the Cochrane library) were searched and, finally, 24 eligible studies were included, with a total of 2105 women from eight countries. A correlational meta-analysis shows that moderate-to-vigorous intensity physical activity (MVPA) was favorably associated with high-density lipoprotein (r = 0.16; 95% CI: 0.06, 0.25; p = 0.002); however, there was limited evidence for the effects of most of the other cardiometabolic biomarkers recorded from steps, total physical activity, light- and moderate-intensity physical activity and MVPA. It is most compelling and consistent that being more physically active is beneficial to the metabolic syndrome. Overall, PA levels are low in adult women, suggesting that increasing the total volume of PA is more important than emphasizing the intensity and duration of PA. The findings also indicate that, according to the confounding effects of body composition and cardiorespiratory fitness, meeting the minimal level of 150 min of moderate-intensity physical activity recommended is not enough to obtain a significant improvement in cardiometabolic indicators. Nonetheless, the high heterogeneity between studies inhibits robust conclusions.

Effects of high protein, low-glycemic index diet on lean body mass, strength, and physical performance in late postmenopausal women: a randomized controlled trial

OBJECTIVE

To investigate whether increasing protein consumption to twice the recommended daily allowance (RDA) by The Institute of Medicine affects lean body mass (LBM), muscle strength, and physical performance in late postmenopausal women.

METHODS

Parallel-group randomized trial with 26 apparently healthy women aged ≥ 65 years. Participants were randomly assigned to low-glycemic index diets with protein consumption at current RDA (0.8 g/kg body weight) or twice the RDA (2RDA, 1.6 g/kg body weight). Protein intake was assessed by 24-hours urinary nitrogen excretion. Change in LBM was measured by dual-energy X-ray absorptiometry at 3 and 6 months. Secondary outcomes were appendicular lean mass, handgrip strength by dynamometry, and physical performance by gait speed.

RESULTS

Mean age was 70.8 ± 3.6 years, and mean BMI was 26.1 ± 3.5 kg/m2 in the overall sample. The RDA and 2RDA groups did not differ regarding baseline dietary intake. Changes from baseline in LBM (0.07 kg; 95% CI, -0.39; 0.52 kg; P = 0.100) and appendicular lean mass (0.07 kg; 95% CI, -0.34; 0.47 kg; P = 0.100) did not differ between the groups. Total body fat (-1.41 kg; 95% CI, -2.62; 0.20 kg; P = 0.019) and trunk fat mass (-0.90 kg; 95% CI, -1.55; -0.24 kg; P = 0.005) decreased similarly in both groups at the end of intervention. Adjusting for baseline BMI did not alter these findings. Handgrip strength and 4-m gait speed increased after the intervention, with no significant difference between the groups.

CONCLUSIONS

Protein intake exceeding the RDA did not increase LBM, strength, and physical performance in a sample of late postmenopausal woman consuming a low-glycemic index diet for 6 months.

Ecological Gait as a Fall Indicator in Older Adults: A Systematic Review

BACKGROUND AND OBJECTIVES

Falls represent a major threat for elders, affecting their life quality and expectancy. Clinical tests and questionnaires showed low diagnostic value with respect to fall risk. Modern sensor technology allows in-home gait assessments, with the possibility to register older adults' ecological mobility and, potentially, to improve accuracy in determining fall risk. Hence, we studied the correlation between standardized assessments and ecological gait measures, comparing their ability to identify fall risk and predict prospective falls.

RESEARCH DESIGN AND METHOD

A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement guidelines.

RESULTS

From a total of 938 studies screened, nine articles with an observational study design were included. Evidence from selected works was subcategorized in (i) correlations between ecological and clinical measures and comparative statistics of (ii) prospective fall prediction and (iii) fall risk identification. A large number of correlations were observed between single ecological gait assessments and multiple clinical fall risk evaluations. Moreover, the combination of daily-life features and clinical tests outcomes seemed to improve diagnostic accuracy in fall risk identification and fall prediction. However, it was not possible to understand the extent of this enhancement due to the high variability in models' parameters.

DISCUSSION AND IMPLICATIONS

Evidence suggested that sensor-based ecological assessments of gait could boost diagnostic accuracy of fall risk measurement protocols if used in combination with clinical tests. Nevertheless, further studies are needed to understand what ecological features of gait should be considered and to standardize models' definition.

Skeletal muscle mass is associated with higher dietary protein intake and lower body fat in postmenopausal women: a cross-sectional study

OBJECTIVE

We investigated the association between skeletal muscle mass and dietary protein intake, habitual physical activity, body composition, and metabolic variables.

METHODS

One hundred three healthy postmenopausal women from southern Brazil (age 55.2 ± 4.9 y, body mass index 27.2 ± 4.6 kg/m) were enrolled. Bone mineral density, %body fat, %trunk fat mass, and appendicular lean mass were assessed by dual-energy x-ray absorptiometry, resting metabolic rate by indirect calorimetry, and habitual physical activity by pedometer. Skeletal muscle mass index (SMI) was expressed as appendicular lean mass standardized to body mass index. The cutoff for low lean mass was <0.512. Protein intake was measured by a validated food frequency questionnaire and categorized into tertiles: ≤0.93 g/kg body weight (BW), 0.94 to 1.29 g/kg BW, and ≥1.3 g protein/kg BW.

RESULTS

The prevalence of low lean mass (SMI <0.512) was 7%. Waist circumference, %body fat, trunk fat mass, and diastolic blood pressure were higher, whereas SMI and mean daily steps were lower in women with protein intake ≤0.93 g/kg BW. SMI was positively correlated with physical activity (r = 0.205, P = 0.038) and protein intake (r = 0.334, P = 0.001), and negatively correlated with waist circumference (r = -0.505, P < 0.001) and %body fat (r = 0.808, P < 0.001). Linear regression analysis adjusted for age, time since menopause, previous smoking behavior, and energy intake showed an independent, positive contribution of protein intake (mean difference 0.007, 95% CI, 0.001-0.014, P = 0.044) and an independent, negative contribution of %body fat (mean difference -0.010, 95%CI, -0.011 to -0.008, P < 0.001) to SMI.

CONCLUSIONS

In our healthy postmenopausal women, SMI was positively associated with protein intake and negatively associated with %body fat.

Habitual physical activity is associated with improved anthropometric and androgenic profile in PCOS: a cross-sectional study

PURPOSE

To examine the effect of habitual physical activity (PA) on the metabolic and hormonal profiles of women with polycystic ovary syndrome.

MATERIALS AND METHODS

Anthropometric, metabolic and hormonal assessment and determination of habitual PA levels with a digital pedometer were evaluated in 84 women with PCOS and 67 age- and body mass index (BMI)-matched controls. PA status was defined according to number of steps (≥7500 steps, active, or <7500 steps, sedentary).

RESULTS

BMI was lower in active women from both groups. Active PCOS women presented lower waist circumference (WC) and lipid accumulation product (LAP) values versus sedentary PCOS women. In the control group, active women also had lower WC, lower values for fasting and 120-min insulin, and lower LAP than sedentary controls. In the PCOS group, androgen levels were lower in active versus sedentary women (p = 0.001). In the control group, free androgen index (FAI) was also lower in active versus sedentary women (p = 0.018). Homeostasis model assessment of insulin resistance and 2000 daily step increments were independent predictors of FAI. Each 2000 daily step increment was associated with a decrease of 1.07 in FAI.

CONCLUSIONS

Habitual PA was associated with a better anthropometric and androgenic profile in PCOS.

The Passo Fundo Cohort Study: design of a population-based observational study of women in premenopause, menopausal transition, and postmenopause

BACKGROUND

The Passo Fundo Cohort Study (PFS) is a population-based longitudinal observational study of pre-, peri-, and postmenopausal women that has been ongoing since 1995 in Passo Fundo, a city in southern Brazil. This paper describes the rationale and design of the PFS and summarizes objectives and procedures that have been updated during follow-up.

METHODS/DESIGN

Women in the PFS have been followed for a variety of diseases that are frequent in menopause. Sampling was conducted in 154 randomly selected census divisions (geographical subdivisions of the city as defined by the Brazilian Institute of Geography and Statistics). One block in each census division was chosen by lot and two women were randomly selected for interview in each block. The first cycle, conducted between 1995 and 1997, included a representative sample of 298 women aged 35 to 55 years. In the second cycle, conducted between 2001 and 2002, additional participants were enrolled based on the same sampling strategy used in 1995, for a final sample of 358 women. In 2010, a third follow-up was initiated, when all 358 participants or their relatives were located. Participants completed a standardized questionnaire on demographic and socioeconomic characteristics. They also answered questions about lifestyle, medical and reproductive characteristics, sexual life, hormone therapy and mental aspects by using validated instruments. Physical activity was assessed and anthropometric measurements, blood sampling and pelvic ultrasound examination were performed. In the third cycle, bone mineral density by dual-energy X-ray absorptiometry and abdominal fat and coronary artery calcium score by computed tomography were also determined.

DISCUSSION

The study findings provide relevant information to evaluate the association between menopausal status, female aging and the risk of cardiovascular diseases, and bone health aspects in a representative sample of women from southern Brazil.

Associations between body composition and lifestyle factors with bone mineral density according to time since menopause in women from Southern Brazil: a cross-sectional study

BACKGROUND

The aim of this study was to investigate whether body composition, dietary pattern and habitual physical activity are associated with BMD according to time since menopause in women from Southern Brazil with no clinical evidence of disease.

METHODS

99 participants were enrolled and anthropometry, body composition and BMD by dual energy x-ray absorptiometry, rest metabolic rate by indirect calorimetry, dietary pattern by semi quantitative food frequency questionnaire and habitual physical activity by pedometer were performed.

RESULTS

Mean age was 55.2 ± 4.9 years and mean time since menopause was 6.8 ± 1.0 years. Weight, BMI, lean and fat mass and RMR were higher in women with less than 5 years since menopause with normal versus low bone mass. No differences were found in the studied variables between participants with normal or low bone mass and more than 5 years of menopause. Women with > 5 years since menopause had higher prevalence of osteoporosis, as well as lower BMD in all sites when compared to those with less time since menopause. Calories, carbohydrate, protein, fat and micronutrients intake were similar between groups. When the sample was adjusted for time since menopause, the odds ratio (OR) for low bone mass was 5.21 (95% CI 1.57-17.25, P = 0.004) for BMI <25 kg/m(2), for lean mass <37.5 Kg an OR of 4.4 (95% CI 1.64-11.80, P = 0.004, for fat mass <26.0 Kg an OR of 3.39 (95% CI 1.29-8.85, P = 0.010) and for the intake of vitamin A < 700 mcg/day an OR of 3.00 (95% CI 1.13-7.94, P = 0.012). Low meat and eggs intake or low protein intake did not influence the odds ratio for low bone mass.

CONCLUSION

In this cross-sectional study with postmenopausal women with no clinical evidence of disease, time since menopause, low lean and fat mass were associated with low bone mass. Calories and macronutrients intake as well as habitual physical activity did not interfere with BMD, but participants were mostly sedentary. Further studies are needed in order to determine whether the adequate intake of specific food groups and the type of physical activity could attenuate the time since menopause impact on BMD.

Physical activity in climacteric women: comparison between self-reporting and pedometer

OBJECTIVE

To compare two methods of assessing physical activity in pre-, peri- and postmenopausal women.

METHODS

Cross-sectional study nested in a cohort of pre-, peri- and postmenopausal women in a city in Southern Brazil. The participants completed a questionnaire that included sociodemographic and clinical data. Physical activity was assessed using a digital pedometer and the International Physical Activity Questionnaire, short version. The participants were classified into strata of physical activity according to the instrument used. For statistical analysis, the Spearman correlation test, Kappa index, concordance coefficient and Bland-Altman plots were used.

RESULTS

The concordance (k = 0110; p = 0.007) and the correlation (rho = 0.136, p = 0.02) between the International Physical Activity Questionnaire, short version, and pedometer were weak. In Bland-Altman plots, it was observed that differences deviate from zero value whether the physical activity is minimal or more intense. Comparing the two methods, the frequency of inactive women is higher when assessed by pedometer than by the International Physical Activity Questionnaire--short version, and the opposite occurs in active women.

CONCLUSIONS

Agreement between the methods was weak. Although easy to use, Physical Activity Questionnaire--short version overestimates physical activity compared with assessment by pedometer.

Association between habitual physical activity and lower cardiovascular risk in premenopausal, perimenopausal, and postmenopausal women: a population-based study

OBJECTIVE

Menopause is associated with an increased risk of cardiovascular disease. Habitual physical activity, defined as any form of body movement with energy expenditure above resting levels, may improve health parameters. We assessed the level of habitual physical activity and its effect on anthropometric measures and cardiovascular risk factors in a cohort of premenopausal, perimenopausal, and postmenopausal women.

METHODS

This cross-sectional study is nested on a longitudinal population-based study that was begun in 1995 in the city of Passo Fundo, Brazil. For the present analysis, 292 women were included. Anthropometric and metabolic profile was evaluated. Habitual physical activity was assessed by a digital pedometer for 7 days, and participants were stratified into active and inactive (≥6,000 and <6,000 steps/day, respectively).

RESULTS

The mean (SD) age was 57.1 (5.4) years. The average number of steps per day for the total sample was 5,250.7 (3,372.9): 3,472.4 (1,570.2) in the inactive group (61.8%) and 9,055.9 (3,033.4) in the active group (31.9%). A negative and statistically significant correlation was found between physical activity and smoking (P = -0.019), body mass index (P = -0.006), waist circumference (P = -0.013), and waist-to-hip ratio of 0.85 or higher (P = -0.043). Inactive women presented a higher risk of overweight/obesity (odds ratio [OR], 2.1; 95% CI, 1.233-3.622; P = 0.006) and waist circumference larger than 88 cm (OR, 1.7; 95% CI, 1.054-2.942; P = 0.03), even after adjustment for age, menopause status, smoking, and hormone therapy. Inactive women also had a higher risk of diabetes mellitus (OR, 2.7; 95% CI, 1.233-6.295; P = 0.014) and metabolic syndrome (OR, 2.5, 95% CI, 1.443-4.294; P = 0.001).

CONCLUSIONS

Habitual physical activity, specifically walking 6,000 or more steps daily, was associated with a decreased risk of cardiovascular disease and diabetes in middle-aged women, independently of menopause status.

Dietary glycemic index is associated with less favorable anthropometric and metabolic profiles in polycystic ovary syndrome women with different phenotypes

OBJECTIVE

To compare glycemic index (GI) in the usual diet of polycystic ovary syndrome (PCOS) and control women and to investigate whether dietary GI is associated with body composition and anthropometric and metabolic variables across PCOS phenotypes.

DESIGN

Cross-sectional study.

SETTING

University hospital outpatient clinic.

PATIENT(S)

Sixty-one women with PCOS and 44 nonhirsute women with ovulatory cycles.

INTERVENTION(S)

Metabolic work-up, biochemical and hormonal assays, assessment of body composition and rest metabolic rate, physical activity (pedometer), and food consumption (food frequency questionnaire).

MAIN OUTCOME MEASURE(S)

GI, glycemic load, dietary intake, and hormone and metabolic profile in PCOS versus control and in PCOS women stratified by tertiles of GI and PCOS phenotype.

RESULT(S)

Mean age was 23.7 ± 6.3 years. Participants with PCOS had higher body fat percentage, fasting insulin, insulin resistance, lipid accumulation product, and androgen levels compared with control women. PCOS and control women in the highest tertile of GI had higher body mass index and waist circumference than those in the lowest tertile. Dietary GI was higher in the classic PCOS group. Obesity and this more severe PCOS phenotype explained 28.3% of variance in dietary GI.

CONCLUSION(S)

Dietary GI is increased in the classic PCOS phenotype and associated with a less favorable anthropometric and metabolic profile. Obesity and classic PCOS phenotype are age-independent predictors of higher dietary GI.

Does the Evaluation of Gait Quality During Daily Life Provide Insight Into Fall Risk? A Novel Approach Using 3-Day Accelerometer Recordings

Background. Many approaches are used to evaluate fall risk. While their properties and performance vary, most reflect performance at a specific moment or are based on subjective self-report. Objective. To quantify fall risk in the home setting using an accelerometer. Methods. Seventy-one community-living older adults were studied. In the laboratory, fall risk was assessed using performance-based tests of mobility (eg, Timed Up and Go) and usual walking abilities were quantified. Subsequently, subjects wore a triaxial accelerometer on their lower back for 3 consecutive days. Acceleration-derived measures were extracted from segments that reflected ambulation. These included total activity duration, number of steps taken, and the amplitude and width at the dominant frequency in the power spectral density, that is, parameters reflecting step-to-step variability. Afterwards, self-report of falls was collected for 6 months to explore the predictive value. Results. Based on a history of 2 or more falls, subjects were classified as fallers or nonfallers. The number of steps during the 3 days was similar ( P = .42) in the fallers (7842.1 ± 6135.6) and nonfallers (9055.3 ± 6444.7). Compared with the nonfallers, step-to-step consistency was lower in the fallers in the vertical axis (amplitude fallers, 0.58 ± 0.22 psd; nonfallers, 0.71 ± 0.18 psd; P = .008); in the mediolateral axis, step-to-step consistency was higher in the fallers ( P = .014). The 3-day measures improved the identification of past and future falls status ( P < .005), compared to performance-based tests. Conclusions. Accelerometer-derived measures based on 3-day recordings are useful for evaluating fall risk as older adults perform daily living activities in their everyday home environment.

A step-defined sedentary lifestyle index: <5000 steps/day

Step counting (using pedometers or accelerometers) is widely accepted by researchers, practitioners, and the general public. Given the mounting evidence of the link between low steps/day and time spent in sedentary behaviours, how few steps/day some populations actually perform, and the growing interest in the potentially deleterious effects of excessive sedentary behaviours on health, an emerging question is "How many steps/day are too few?" This review examines the utility, appropriateness, and limitations of using a reoccurring candidate for a step-defined sedentary lifestyle index: <5000 steps/day. Adults taking <5000 steps/day are more likely to have a lower household income and be female, older, of African-American vs. European-American heritage, a current vs. never smoker, and (or) living with chronic disease and (or) disability. Little is known about how contextual factors (e.g., built environment) foster such low levels of step-defined physical activity. Unfavorable indicators of body composition and cardiometabolic risk have been consistently associated with taking <5000 steps/day. The acute transition (3-14 days) of healthy active young people from higher (>10 000) to lower (<5000 or as low as 1500) daily step counts induces reduced insulin sensitivity and glycemic control, increased adiposity, and other negative changes in health parameters. Although few alternative values have been considered, the continued use of <5000 steps/day as a step-defined sedentary lifestyle index for adults is appropriate for researchers and practitioners and for communicating with the general public. There is little evidence to advocate any specific value indicative of a step-defined sedentary lifestyle index in children and adolescents.

Cardiac autonomic modulation in polycystic ovary syndrome: does the phenotype matter?

OBJECTIVE

To assess whether heart rate variability (HRV) at rest and during sympathetic stimulation is disturbed in patients with different polycystic ovary syndrome (PCOS) phenotypes in comparison to healthy controls.

DESIGN

Cross-sectional study.

SETTING

University hospital.

PATIENT(S)

Thirty women with classic, anovulatory PCOS, 16 women with ovulatory PCOS, and 23 age-paired women with regular and proven ovulatory cycles.

INTERVENTION(S)

Anthropometric and hormonal evaluation and analysis of HRV (time and frequency domain HRV indices) at rest and after a mental stress test.

MAIN OUTCOME MEASURE(S)

Difference between HRV components during rest and stress.

RESULT(S)

Mean age was 22.80 ± 5.80 years in patients with classic PCOS, 19.81 ± 6.43 years in ovulatory PCOS, and 22.65 ± 5.89 years in controls. During mental stress, patients with classic PCOS showed lower HRV response when compared with the control group, even after adjustment for body mass index (BMI) and age. When patients with classic and ovulatory PCOS were considered together, total T levels were inversely associated with the low frequency component, low frequency/high frequency ratio, and the difference between high frequency response at rest and after the stress test.

CONCLUSION(S)

Young patients with the classic PCOS phenotype have an impaired autonomic modulation in response to sympathetic stimulation that is typical of considerably older women, or of advanced age.