Exercise program affects body composition but not weight in postmenopausal women

Effect of a Culturally Adapted Exercise Program on the Anthropometrics and Body Composition of Postmenopausal Women With Excess Weight Gain: A Randomized Controlled Trial

Background

Physical activity (PA) is recommended as a component of weight management for the prevention of weight gain and weight regain after weight loss. Yet, no study has adapted culturally appropriate PA for postmenopausal women's health.

Aims

The study aimed to investigate the effect of a developed culturally appropriate exercise program for Ghanaian postmenopausal women with excess weight gain on the anthropometrics and body composition.

Material and methods

A single-blind randomized controlled trial in which participants randomly received a culturally-induced exercise program. A total of 226 Ghanaian postmenopausal women were randomized into exercise and control groups for 12 weeks. Anthropometrics (body mass index [BMI], waist-to-hip ratio [WHR], waist-to-height ratio [WHtR] waist circumference [WC], hip circumference [HC], and weight) and body composition (body fat, visceral fat, muscle mass) were determined pre-and post-intervention.

Results

Average of 58.70 ± 6.38 years (p > 0.05) with more than half (52.1%) above 58 years. Except for WHR, there were statistically significant differences in weight, BMI, WHtR, visceral fat, and total body fat in the exercise and control groups. Muscle mass increased significantly (+0.21 kg), whereas HC (-2.46 cm) and WC (-1.39 cm) decreased significantly compared with the control group. Within the exercise group, when stratified by BMI, there were higher reductions in BMI (1.01 kg/m2 vs. 0.46 kg/m2), WC (2.18 cm vs. 0.22 cm), body weight (2.12 kg vs. 1.17 kg) and body fat (1.84% vs. 1.6%) in women with obesity compared with women with overweight.

Conclusion

The promotion of Indigenous physical activity in postmenopausal women is beneficial. This has implications for health professionals who prescribe physical activity in postmenopausal women's treatment plans.

Trial Registration

PACTR202301779437544.

Estrogen modulates metabolic risk profile after resistance training in early postmenopausal women: a randomized controlled trial

OBJECTIVE

Women experience an unhealthy change in metabolic risk profile at menopause. The purpose of the present study was to determine effects of resistance training with or without transdermal estrogen therapy (ET) on adipose tissue mass and metabolic risk profile in early postmenopausal women.

METHODS

A double-blinded randomized controlled trial, where healthy, untrained postmenopausal women were allocated to supervised resistance training with placebo (PLC, n = 16) or transdermal ET (n = 15) for 12 weeks. Endpoints with prespecified hypotheses were the change in total fat mass (FM) (main endpoint) and the change in visceral FM (secondary endpoint) from before to after the intervention. Additionally, prespecified endpoints of body composition, metabolic health-related blood markers, fat%, fat cell size, and lipogenic markers in subcutaneous adipose tissue (SAT) from abdominal and femoral region were explored.

RESULTS

Compared with the ET group, the PLC group experienced a greater reduction (time × treatment interaction P < 0.05) in total FM (PLC vs ET: -5.6% vs -1.1%) and visceral FM (-18.6% vs -6.8%), and femoral SAT (-5.6% vs 1.0%), but not abdominal SAT mass (-8.5% vs -2.8%, P = 0.15).The ET group improved their metabolic blood profile by reduced low-density lipoprotein, glucose and hemoglobin A1c compared with PLC (time × treatment interaction P < 0.05). The intervention induced changes in lipolytic markers of abdominal SAT, whereas no changes were detected in femoral SAT.

CONCLUSION

Use of transdermal ET reduced adipose tissue loss, but improved metabolic blood markers when combined with 12 weeks of progressive resistance training in early postmenopausal women.

[Effects of physical activity and decreased sedentary behaviours in menopausal women. Postmenopausal women management: CNGOF and GEMVi clinical practice guidelines]

The purpose of this chapter is to examine, in postmenopausal women, the effect of physical activity (PA) on overall mortality, cardiovascular mortality and prevention of cardiovascular disease, bone health and body composition. An analysis of the scientific literature was carried out and more than 100 studies were selected. In postmenopausal women, regular endurance PA significantly reduced overall and cardiovascular mortality. It is effective in primary and tertiary prevention. Regarding bone health, combined exercises combining weight-bearing exercises with impacts associated with muscle strengthening are the most effective to maintain or improve bone mineral density and prevent fractures. In terms of body composition, regular endurance or combined PA (endurance+muscle strengthening) decreases visceral fat regardless of BMI, and this in the absence of caloric restriction. For muscle mass, only muscle strengthening or combined training (endurance+muscle strengthening) have shown their effectiveness in slowing down the loss of muscle mass or even in increasing it. In all cases, the minimum duration of PA is 12 weeks and above all, it must be continued so that the effects are maintained over the long term. All these parameters will also be improved with a reduction in time spent sitting, regardless of the level of PA. No study has reported a major incident related to the practice of moderate to high intensity levels of PA, provided that certain precautions are observed, the main one being with regard to cardiovascular risk. The recommendations for postmenopausal women are a reduction in sedentary behaviour associated with specific recommendations for regular physical activity.

The Effect of Low-Volume High-Intensity Interval Training on Body Composition and Cardiorespiratory Fitness: A Systematic Review and Meta-Analysis

BACKGROUND

Evidence for the efficacy of low-volume high-intensity interval training (HIIT) for the modulation of body composition is unclear.

OBJECTIVES

We examined the effect of low-volume HIIT versus a non-exercising control and moderate-intensity continuous training (MICT) on body composition and cardiorespiratory fitness in normal weight, overweight and obese adults. We evaluated the impact of low-volume HIIT (HIIT interventions where the total amount of exercise performed during training was ≤ 500 metabolic equivalent minutes per week [MET-min/week]) compared to a non-exercising control and MICT.

METHODS

A database search was conducted in PubMed (MEDLINE), EMBASE, CINAHL, Web of Science, SPORTDiscus and Scopus from the earliest record to June 2019 for studies (randomised controlled trials and non-randomised controlled trials) with exercise training interventions with a minimum 4-week duration. Meta-analyses were conducted for between-group (low-volume HIIT vs. non-exercising control and low-volume HIIT vs. MICT) comparisons for change in total body fat mass (kg), body fat percentage (%), lean body mass (kg) and cardiorespiratory fitness.

RESULTS

From 11,485 relevant records, 47 studies were included. No difference was found between low-volume HIIT and a non-exercising control on total body fat mass (kg) (effect size [ES]: - 0.129, 95% confidence interval [CI] - 0.468 to 0.210; p = 0.455), body fat (%) (ES: - 0.063, 95% CI - 0.383 to 0.257; p = 0.700) and lean body mass (kg) (ES: 0.050, 95% CI - 0.250 to 0.351; p = 0.744), or between low-volume HIIT and MICT on total body fat mass (kg) (ES: - 0.021, 95% CI - 0.272 to 0.231; p = 0.872), body fat (%) (ES: 0.005, 95% CI - 0.294 to 0.304; p = 0.974) and lean body mass (kg) (ES: 0.030, 95% CI - 0.167 to 0.266; p = 0.768). However, low-volume HIIT significantly improved cardiorespiratory fitness compared with a non-exercising control (p < 0.001) and MICT (p = 0.017).

CONCLUSION

These data suggest that low-volume HIIT is inefficient for the modulation of total body fat mass or total body fat percentage in comparison with a non-exercise control and MICT. A novel finding of our meta-analysis was that there appears to be no significant effect of low-volume HIIT on lean body mass when compared with a non-exercising control, and while most studies tended to favour improvement in lean body mass with low-volume HIIT versus MICT, this was not significant. However, despite its lower training volume, low-volume HIIT induces greater improvements in cardiorespiratory fitness than a non-exercising control and MICT in normal weight, overweight and obese adults. Low-volume HIIT, therefore, appears to be a time-efficient treatment for increasing fitness, but not for the improvement of body composition.

Effects of a short workplace exercise program on body composition in women: A randomized controlled trial

Physical inactivity and poor diet cause alterations in body composition, which in turn increases risk factors for cardiovascular and metabolic diseases. Sixty-three women from different work environments were randomly assigned to an intervention (n = 34) or control (n = 29) group. The intervention was a short-term aerobic exercise program (12 weeks) at their workplace. Participants assigned to the control group did not perform any form of physical exercise. Body composition was measured by dual-energy X-ray absorptiometry (DXA). Diet was assessed using the Mediterranean Diet Quality Questionnaire (KIDMED) and nutrient balance by the Food Frequency Questionnaire. Researchers suggest that a short-term aerobic exercise program produces beneficial effects on body composition.

Effects of dietary and exercise intervention on weight loss and body composition in obese postmenopausal women: a systematic review and meta-analysis

OBJECTIVE

This study examined the effects of dietary and exercise interventions on weight loss and body composition in overweight/obese peri- and postmenopausal women.

METHODS

Medline, Central, Embase, and Google Scholar databases were searched for relevant trials conducted until December 31, 2016. Randomized controlled trials (RCTs) and prospective studies of overweight/obese peri- or postmenopausal women that examined the effects of dietary or exercise interventions, alone or combined, on weight loss were included. The primary outcome was percentage reduction in body weight.

RESULTS

From 292 studies initially identified, 11 studies with 12 sets of participants were included. Both dietary and exercise intervention groups had significantly greater weight loss than control groups (diet vs control: difference in means = -6.55, 95% CI, -9.51 to -3.59, P < 0.001; exercise vs control: difference in means = -3.49, 95% CI, -6.96 to -0.02, P = 0.049). Combined dietary and exercise interventions resulted in greater weight loss than dietary interventions alone (diet plus exercise vs diet: difference in means = -1.22, 95% CI, -2.14 to -0.29, P = 0.010). Diet plus exercise resulted in greater fat loss (difference in means = -0.44, 95% CI, -0.67 to -0.20, P < 0.001) and greater lean mass loss (difference in means = -0.84, 95% CI, -1.13 to -0.55, P < 0.001) than diet alone.

CONCLUSIONS

Dietary interventions reduced body weight and body composition profile parameters in peri- and postmenopausal women more than exercise alone. The addition of exercise reinforced the effect of dietary interventions on changing body weight and composition.

Studying a Possible Placebo Effect of an Imaginary Low-Calorie Diet

In recent years the prevalence of obesity in developed countries has increased to the point that some authorities have coined the term "obesity epidemics." Combining energy intake control measures (via diet) with protocols for increasing energy expenditure (predominantly via low to medium intensity aerobic exercise) proved to be the most effective approach in addressing this problem. In this experiment, we studied for a possible placebo effect of a weight loss program on changes in body mass and fat tissue in overweight or obese people. Fourteen healthy adults of both sexes aged between 19 and 45 with body mass index (BMI) > 27 participated in the study. They were randomly assigned to two groups-one experimental and one control. The subjects in the experimental group followed an isocaloric diet but were told they were put on a calorie-deficient regimen. The subjects in the control group were aware they followed an energy-balanced diet. All participants were engaged in regular sessions of resistance exercise three times a week with total energy cost of approximately 750-900 kcal/week. We studied within-group differences of body mass, percentage of fat tissue, and BMI. All three variables reduced in value in the experimental group: body mass-9.25 ± 5.26 kg, percentage of fat tissue-3.4 ± 0.97%, and BMI-2.88 ± 1.50. No statistically significant within-group differences were measured in the control group. Despite some methodological biases of the study construct, in our opinion, a placebo effect could partially explain the changes in the experimental group.

Dose–response effects of aerobic exercise on energy compensation in postmenopausal women: combined results from two randomized controlled trials

Background/objectives:

Despite the clear health benefits of exercise, exercised-induced weight loss is often less than expected. The term ‘exercise energy compensation’ is used to define the amount of weight loss below what is expected for the amount of exercise energy expenditure. We examined the dose–response effects of exercise volume on energy compensation in postmenopausal women.

Participants/methods:

Data from Alberta Physical Activity and Breast Cancer Prevention (ALPHA) and Breast Cancer and Exercise Trial in Alberta (BETA) were combined for the present analysis. The ALPHA and BETA trials were two-centred, two-armed, 12-month randomized controlled trials. The ALPHA trial included 160 participants randomized to 225 min per week of aerobic exercise, and the BETA trial randomized 200 participants to each 150 and 300 min per week of aerobic exercise. All participants were aged 50–74 years, moderately inactive (<90 min per week of exercise), had no previous cancer diagnosis and a body mass index between 22 and 40 kg m⁻². Energy compensation was based on changes in body composition (dual-energy X-ray absorptiometry scan) and estimated exercise energy expenditure from completed exercise volume. Associations between Δenergy intake, ΔVO_2peak and Δphysical activity time with energy compensation were assessed.

Results:

No differences in energy compensation were noted between interventions. However, there were large inter-individual differences in energy compensation between participants; 9.4% experienced body composition changes that were greater than expected based on exercise energy expenditure, 64% experienced some degree of energy compensation and 26.6% experienced weight gain based on exercise energy expenditure. Increases in VO_2peak were associated with reductions in energy compensation (β=−3.44 ml kg⁻¹ min⁻¹, 95% confidence interval for β=−4.71 to −2.17 ml kg⁻¹ min⁻¹; P=0.0001).

Conclusions:

Large inter-individual differences in energy compensation were noted, despite no differences between activity doses. In addition, increases in VO_2peak were associated with lower energy compensation. Future studies are needed to identify behavioral and metabolic factors that may contribute to this large inter-individual variability in energy compensation.

Effect of resistance training with elements of stretching on body composition and quality of life in postmenopausal women

INTRODUCTION

Physical activity in elderly persons contributes to prevention and treatment of chronic disease and, through its influence on the musculoskeletal system, increases physical capability and improves mental function.

AIM OF THE STUDY

Aim of the study was to assess the effect of resistance training with elements of stretching on body composition and quality of life in women of postmenopausal age.

MATERIAL AND METHODS

Thirty-eight postmenopausal women aged 62.5 ±5.8 years were randomly divided into two groups. One group participated in an 8-week training program (60 minutes, twice weekly; 4 MET [metabolic equivalent] 2 hours/week). The second group performed no training. A comparison was made of body composition and quality of life (SF-36 Health Survey) prior to and after 8 weeks of training.

RESULTS

In the training group, after 8 weeks there was a significant reduction in body fat (in%; p = 0.028), and an increase in fat-free mass (in%; p = 0.025) and total body water (in%; p = 0.021), which indicates increased muscle mass. Furthermore, there were statistically significant differences in the assessment of quality of life in physical (role-physical [RP], bodily pain [BP], general health [GH] scales; p < 0.005) and mental health (vitality [VT] scale; p = 0.05). In the non-exercising group no changes were observed in features examined in the initial and final test.

CONCLUSIONS

Resistance training with elements of stretching in postmenopausal women improved body composition to achieve a reduction in risk factors associated with excess fatty tissue and muscle mass deficiency. It raises the quality of life in terms of both physical and mental function.

Effect of physical activity on sex hormones in women: a systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

Exposure to high levels of endogenous estrogens is a main risk factor for breast cancer in women, and in observational studies was found to be inversely associated with physical activity. The objective of the present study is to determine the effect of physical activity interventions on sex hormone levels in healthy women.

METHODS

Electronic databases (MEDLINE, EMBASE, CENTRAL), from inception to December 2014, and reference lists of relevant reviews and clinical trials were searched, with no language restrictions applied. Randomized controlled trials (RCTs) were included if they compared any type of exercise intervention to no intervention or other interventions, and assessed the effects on estrogens, androgens or the sex hormone binding globulin (SHBG) in cancer-free women. Following the method described in the Cochrane Handbook for Systematic Reviews of Interventions, data on populations, interventions, and outcomes were extracted, and combined using the inverse-variance method and a random-effects model. A pre-established protocol was drawn up, in which the primary outcome was the difference in circulating estradiol concentrations between the physical activity (experimental) and the control groups after intervention. Pre-specified subgroup analyses and sensitivity analysis according to the risk of bias were conducted.

RESULTS

Data suitable for quantitative synthesis were available from 18 RCTs (1994 participants) for total estradiol and from 5 RCTs (1245 participants) for free estradiol. The overall effect of physical activity was a statistically significant decrease of both total estradiol (standardized mean difference [SMD] -0.12; 95 % confidence interval [CI] -0.20 to -0.03; P = 0.01; I (2) = 0 %) and free estradiol (SMD -0.20; 95 % CI -0.31 to -0.09; P = 0.0005; I (2) = 0 %). Subgroup analyses suggest that this effect is independent of menopausal status and is more noticeable for non-obese women and for high intensity exercise. Meta-analysis for secondary outcomes found that physical activity induces a statistically significant decline of free testosterone, androstenedione, dehydroepiandrosterone-sulfate and adiposity markers, while a significant increase of SHBG was observed.

CONCLUSIONS

Although the effect is relatively modest, physical activity induces a decrease in circulating sex hormones and this effect is not entirely explained by weight loss. The findings emphasize the benefits of physical activity for women.

Effect of exercise on insulin sensitivity in healthy postmenopausal women: the SHAPE study

BACKGROUND

An inactive lifestyle is a risk factor for several types of cancer. A proposed pathway through which exercise influences cancer risk is via insulin. We aim to investigate the effect of a one-year exercise intervention on insulin sensitivity, and the role of body fat in this association, in healthy, normal to overweight/obese, postmenopausal women.

METHODS

In the Sex Hormones And Physical Exercise (SHAPE) study, 189 healthy, inactive and postmenopausal women [ages, 50-69 years; body mass index (BMI), 22-40 kg/m(2)] were randomly assigned to a one-year aerobic and strength exercise intervention (150 min/wk), or a control group. Between-group differences in fasting insulin, glucose, and homeostatic model assessment of insulin resistance (HOMA2) over time were estimated using linear mixed models.

RESULTS

Follow-up measurements of insulin sensitivity were available for 181 (95.8%) and 182 (96.3%) women at 4 and 12 months, respectively. The intention-to-treat analysis showed no significant differences between the two study groups [treatment effect ratio of the exercise group vs. control (β; 95% confidence interval): insulin, β, 1.07 (0.96-1.19); glucose, β, 1.01 (0.99-1.02); and HOMA2, β, 1.07 (0.96-1.20)]. Similar results were found in a per protocol analysis in compliant women, and in a subgroup of women who lost >2% body fat [measured by dual-energy X-ray absorptiometry (DEXA)].

CONCLUSIONS

Participation in a one-year aerobic and strength exercise intervention program did not result in changes in insulin sensitivity in healthy postmenopausal and inactive women.

IMPACT

Our findings suggest that 150 min/wk of exercise, as recommended by current guidelines, is not enough to achieve improvements in insulin sensitivity and subsequent cancer risk, in healthy postmenopausal women.

The effects of different exercise programmes on female body composition

The purpose of this study was to verify the effects of 16 weeks of practicing different exercise programmes on body composition. This is an exploratory and descriptive study of 89 women aged 25 to 55 years (41.42 ± 9.23 years). The subjects were randomly divided into three experimental groups (EG): practitioners of strength training (SG), dance (DG), hydrogymnastics (HG), and a control group (CG) with sedentary women. Measurements of body mass and height, circumferences of the chest, waist, abdomen, hips, thighs, calves, and skinfolds of the triceps, suprailiac and thigh were registered in three different moments: prior to the commencement of the training program, again after 8 weeks of training, and finally after 16 weeks of training. Body density was estimated by using the trifold protocol by Jackson, Pollock and Ward. The ANOVA and deltas of change (Δ%) were used for data analysis. The level of significance was set at p<0.05. The effects of greater statistical significance on body composition related the variables “time”, “group” and the interaction between the two (time × group) were observed for the percentage of fat - F% (F (1.79, 152.52) = 24.59, p <0.001, η ² = 0.22), fat mass - FM (F (1.75, 149.01) = 12.65, p <0.001, η ² = 0.13) and lean mass - LM (F (1.77, 150.66) = 47.38, p <0.001, η ² = 0.36). The HG and SG were more beneficial in reducing F%. It was observed that the EG indicated healthier anthropometric aspects compared to the CG, regardless of the type of exercise programmes practiced. The time factor was more representative over the effects of exercise on anthropometric dimensions.

The effect of physical exercise on postpartum fitness, hormone and lipid levels: a randomized controlled trial in primiparous, lactating women

PURPOSE

To evaluate the effect of an exercise training program combining low-impact dance aerobic, resistance and stretching exercise on physical fitness, hormone and lipid levels of postpartum, primiparous, lactating women.

METHODS

Thirty seven primiparous, lactating women were randomly assigned at 4-6 weeks postpartum to either follow an exercise training program of 50-60 min aerobic, strengthening and stretching exercise, 3 days a week, for 12 weeks (interventional group; n = 20) or no training program at all (control group; n = 17). The following parameters were measured at baseline and 12 weeks later: (1) for evaluation of physical fitness: VO2max, muscular endurance, joint mobility and body fat; (2) for evaluation of the lipidemic profile: triglyceride, total cholesterol, HDL and LDL levels, and (3) levels of hormones associated with lactation: prolactin, estradiol, cortisol, TSH, fT3 and fT4.

RESULTS

After completion of the exercise training program, comparisons between the interventional and the control group showed statistically significant mean changes in VO2max (p = 0.003), muscular endurance of the upper extremities (p < 0.001), and the abdomen (p < 0.001), flexibility (p = 0.042), and body fat (p = 0.007). There were no significant differences between the two groups in mean changes of lipid and hormone levels.

CONCLUSION

Implementation of a low-impact exercise training program appears to improve physical fitness of postpartum women, while it does not seem to affect lipid levels and lactation-associated hormone levels. Hence, implementation of an exercise training program combining low-impact dance aerobic, resistance and stretching exercise is feasible in postpartum, primiparous, lactating women.

The Influence of Energetic Factors on Biomarkers of Postmenopausal Breast Cancer Risk

Strong and consistent evidence exists that physical activity reduces breast cancer risk by 10-25 %, and several proposed biologic mechanisms have now been investigated in randomized, controlled, exercise intervention trials. Leading hypothesized mechanisms relating to postmenopausal breast cancer include adiposity, endogenous sex hormones, insulin resistance, and chronic low-grade inflammation. In addition, other pathways are emerging as potentially important, including those involving oxidative stress and telomere length, global DNA hypomethylation, immune function, and vitamin D exposure. Recent exercise trials in overweight/obese postmenopausal women implicate weight loss as a mechanism whereby exercise induces favorable changes in circulating estradiol levels and other biomarkers as well. Still it is plausible that some exercise-induced biomarker changes do not require loss of body fat, whereas others depend on abdominal fat loss. We highlight the latest findings from randomized, controlled trials of healthy postmenopausal women, relating exercise to proposed biomarkers for postmenopausal breast cancer risk.

Design of the SHAPE-2 study: the effect of physical activity, in addition to weight loss, on biomarkers of postmenopausal breast cancer risk

Background

Physical inactivity and overweight are two known risk factors for postmenopausal breast cancer. Former exercise intervention studies showed that physical activity influences sex hormone levels, known to be related to postmenopausal breast cancer, mainly when concordant loss of body weight was achieved. The question remains whether there is an additional beneficial effect of physical activity when weight loss is reached.

The aim of this study is to investigate the effect attributable to exercise on postmenopausal breast cancer risk biomarkers, when equivalent weight loss is achieved compared with diet-induced weight loss.

Design

The SHAPE-2 study is a three-armed, multicentre trial. 243 sedentary, postmenopausal women who are overweight or obese (BMI 25–35 kg/m²) are enrolled. After a 4-6 week run-in period, wherein a baseline diet is prescribed, women are randomly allocated to (1) a diet group, (2) an exercise group or (3) a control group. The aim of both intervention groups is to lose an amount of 5–6 kg body weight in 10–14 weeks. The diet group follows an energy restricted diet and maintains the habitual physical activity level. The exercise group participates in a 16-week endurance and strength training programme of 4 hours per week. Furthermore, they are prescribed a moderate caloric restriction. The control group is asked to maintain body weight and continue the run-in baseline diet.

Measurements include blood sampling, questionnaires, anthropometrics (weight, height, waist and hip circumference), maximal cycle exercise test (VO_2peak), DEXA-scan (body composition) and abdominal MRI (subcutaneous and visceral fat). Primary outcomes are serum levels of oestradiol, oestrone, testosterone and sex hormone binding globulin (SHBG).

Discussion

This study will give insight in the potential attributable effect of physical activity on breast cancer risk biomarkers and whether this effect is mediated by changes in body composition, in postmenopausal women. Eventually this may lead to the design of specific lifestyle guidelines for prevention of breast cancer.

Trial registration

The SHAPE-2 study is registered in the register of clinicaltrials.gov, Identifier: NCT01511276.

Mild obesity, physical activity, calorie intake, and the risks of cervical intraepithelial neoplasia and cervical cancer

Objective

We investigated whether obesity, physical activity, and calorie intake are associated with the risks of cervical intraepithelial neoplasia (CIN) and cervical cancer.

Methods

We enrolled 1125 women (age, 18–65 years) into a human papillomavirus cohort study established from 2006 to 2012. Multinomial logistic regression models were used to estimate crude and multivariate odds ratios (ORs) and the corresponding 95% confidence intervals (95% CIs), and to assess whether body mass index (BMI), height, weight, total calorie intake, and physical activity were associated with the risks of CIN and cervical cancer.

Results

Cervical cancer risk was positively associated with BMI and inversely associated with physical activity. When compared with women with a normal BMI (18.5–23 kg/m²), the multivariate ORs (95% CIs) for those overweight (23–25 kg/m²) and mild obesity (≥25 kg/m²) were 1.25 (0.79–2.00) and 1.70 (1.10–2.63), respectively. When compared with women with the lowest tertile of physical activity (<38.5 MET-hours/week), the ORs (95% CIs) for cervical cancer were 0.95 (0.61–1.48) and 0.61 (0.38–0.98) for women with medium physical activity (38.5–71.9 MET-hours/week) and those with high physical activity (72 MET-hours/week), respectively (p for linear trend  = 0.03). The CIN2/3 risk was inversely associated with physical activity after adjustment for confounders. Compared with women with low physical activity (< 38.5 MET-hours/week), the ORs (95% CIs) for CIN2/3 were 0.64 (0.40–1.01) and 0.58 (0.36–0.93) for the medium and high physical activity groups, respectively (p for linear trend  = 0.02). Total calorie intake was not statistically associated with the risks of CIN and cervical cancer after adjustment for confounders.

Conclusion

Our results indicate that in addition to screening for and treatment of CIN, recommendations on the maintenance of an appropriate BMI with an emphasis on physical activity could be an important preventive strategy against the development of cervical cancer.

Effects of chronic swimming training and oestrogen therapy on coronary vascular reactivity and expression of antioxidant enzymes in ovariectomized rats

The aim of this study was to evaluate the effects of swimming training (SW) and oestrogen replacement therapy (ERT) on coronary vascular reactivity and the expression of antioxidant enzymes in ovariectomized rats. Animals were randomly assigned to one of five groups: sham (SH), ovariectomized (OVX), ovariectomized with E2 (OE2), ovariectomized with exercise (OSW), and ovariectomized with E2 plus exercise (OE2+SW). The SW protocol (5×/week, 60 min/day) and/or ERT were conducted for 8 weeks; the vasodilator response to bradykinin was analysed (Langendorff Method), and the expression of antioxidant enzymes (SOD-1 and 2, catalase) and eNOS and iNOS were evaluated by Western blotting. SW and ERT improved the vasodilator response to the highest dose of bradykinin (1000 ng). However, in the OSW group, this response was improved at 100, 300 and 1000 ng when compared to OVX (p<0,05). The SOD-1 expression was increased in all treated/trained groups compared to the OVX group (p<0,05), and catalase expression increased in the OSW group only. In the trained group, eNOS increased vs. OE2, and iNOS decreased vs. SHAM (p<0,05). SW may represent an alternative to ERT by improving coronary vasodilation, most likely by increasing antioxidant enzyme and eNOS expression and augmenting NO bioavailability.

Physical activity and body composition, body physique, and quality of life in premenopausal breast cancer patients during endocrine therapy--a feasibility study

Endocrine therapy (ET) is a common method of treatment in breast cancer patients; however, its negative impact on body composition, body physique (physical body shape/measurements), and quality of life (QoL) remains controversial. Previous studies have shown physical exercise can have a positive effect on QoL in breast cancer patients, especially premenopausal subjects.

OBJECTIVE

In this feasibility study, we sought to assess the impact that physical exercise had on body composition and QoL in premenopausal breast cancer patients undergoing ET, and to determine the appropriateness of further testing of this intervention in this patient group.

MATERIAL AND METHODS

This study involved 41 premenopausal female breast cancer patients before and after six, 12, and 18 months of ET. Aerobic training began in the 6th month and resistance training was added in the 12th month. Body composition was evaluated using dual-energy x-ray absorptiometry (DXA) scans, body physique was evaluated using anthropometric measurement techniques, and QoL was evaluated using questionnaires from the European Organization for Research and Treatment of Cancer.

RESULTS

The initial period of ET with no exercise resulted in a reduction in fat-free body mass (FFBM), an increase in fat body mass (FBM), and a decline in QoL scores. Adding aerobic training resulted in a reduction of FBM and percentage of android fat, and improved QoL scores. The introduction of resistance training further reduced percentage of android and gynoid fat, increased FFBM, and further improved QoL scores.

CONCLUSION

ET negatively impacts body composition, body physique, and QoL of premenopausal breast cancer patients. This feasibility study shows that physical activity may improve QoL and reduce adverse effects of ET on body composition and body physique, indicating appropriateness for further investigation on the use of exercise programs in premenopausal breast cancer patients to improve the outcomes of therapy.

Different anthropometric adiposity measures and their association with cardiovascular disease risk factors: a meta-analysis

Objectives

To investigate which anthropometric adiposity measure has the strongest association with cardiovascular disease (CVD) risk factors in Caucasian men and women without a history of CVD.

Design

Systematic review and meta-analysis.

Methods

We searched databases for studies reporting correlations between anthropometric adiposity measures and CVD risk factors in Caucasian subjects without a history of CVD. Body mass index (BMI), waist circumference, waist-to-hip ratio, waist-to-height ratio and body fat percentage were considered the anthropometric adiposity measures. Primary CVD risk factors were: systolic blood pressure, diastolic blood pressure, high density lipoprotein (HDL) cholesterol, triglycerides and fasting glucose. Two independent reviewers performed abstract, full text and data selection.

Results

Twenty articles were included describing 21,618 males and 24,139 females. Waist circumference had the strongest correlation with all CVD risk factors for both men and women, except for HDL and LDL in men. When comparing BMI with waist circumference, the latter showed significantly better correlations to CVD risk factors, except for diastolic blood pressure in women and HDL and total cholesterol in men.

Conclusions

We recommend the use of waist circumference in clinical and research studies above other anthropometric adiposity measures, especially compared with BMI, when evaluating CVD risk factors.

Alternatives for randomization in lifestyle intervention studies in cancer patients were not better than conventional randomization

OBJECTIVE

Assessing effects of lifestyle interventions in cancer patients has some specific challenges. Although randomization is urgently needed for evidence-based knowledge, sometimes it is difficult to apply conventional randomization (i.e., consent preceding randomization and intervention) in daily settings. Randomization before seeking consent was proposed by Zelen, and additional modifications were proposed since. We discuss four alternatives for conventional randomization: single and double randomized consent design, two-stage randomized consent design, and the design with consent to postponed information.

STUDY DESIGN AND SETTING

We considered these designs when designing a study to assess the impact of physical activity on cancer-related fatigue and quality of life. We tested the modified Zelen design with consent to postponed information in a pilot. The design was chosen to prevent drop out of participants in the control group because of disappointment about the allocation.

RESULTS

The result was a low overall participation rate most likely because of perceived lack of information by eligible patients and a relatively high dropout in the intervention group.

CONCLUSION

We conclude that the alternatives were not better than conventional randomization.

Physical activity and breast cancer prevention

Breast cancer is the most commonly diagnosed invasive malignancy and the second leading cause of cancer death in women. This chapter considers epidemiologic evidence regarding the association between physical activity and breast cancer risk from 73 studies conducted around the world. Across these studies there was a 25% average risk reduction amongst physically active women as compared to the least active women. The associations were strongest for recreational activity, for activity sustained over the lifetime or done after menopause, and for activity that is of moderate to vigorous intensity and performed regularly. There is also some evidence for a stronger effect of physical activity amongst postmenopausal women, women who are normal weight, have no family history of breast cancer, and are parous. It is likely that physical activity is associated with decreased breast cancer risk via multiple interrelated biologic pathways that may involve adiposity, sex hormones, insulin resistance, adipokines, and chronic inflammation. Future research should include prospective observational epidemiologic studies relating proposed biomarkers to breast cancer risk and also randomized controlled trials to examine how physical activity influences the proposed biomarkers. Exercise trials will provide more clarity regarding the appropriate type, dose, and timing of activity that relate to breast cancer risk reduction.

What is the role played by physical activity and exercise in the frailty syndrome? Perspectives for future research

Exercise and physical activity play an important role in physical frailty, but we do not know if they are markers, components and/or correlates of this syndrome. The purpose of this paper is briefly to discuss the potential roles played by physical activity and exercise on the development and progression of frailty, and to propose directions for future research in this field. Exercise practice lowers the levels of some frailty markers, such as tumor necrosis factor-alpha, interleukin-6, C-reactive protein, and uric acid, and also resistance to insulin. The influence of exercise on the main frailty domains is also well established in the literature. Exercise improves muscle strength, gait speed, cognition (particularly executive control related-tasks), weight maintenance, mood and, to a lesser extent, feelings of energy. Although exercise and physical activity positively influence the main frailty markers and domains, most findings were obtained for other elderly populations (e.g., healthy elderly, clinical populations). For future research, efforts must be made to define some key concepts (exercise or physical activity) in selecting study samples and in establishing intervention length. Attention must also be paid to identifying the most efficacious exercise interventions regarding type, frequency, intensity and session duration, and approaching a dose-response relationship between a physically active life-style and frailty. Thus, further research, especially longitudinal randomized controlled trials, is needed to understand the role of physical activity and exercise in the frailty syndrome.

Adiposity changes after a 1-year aerobic exercise intervention among postmenopausal women: a randomized controlled trial

Objective:

We examined the effects of an aerobic exercise intervention on adiposity outcomes that may be involved in the association between physical activity and breast cancer risk.

Design:

This study was a two-centre, two-armed, randomized controlled trial. The 1-year-long exercise intervention included 45 min of moderate-to-vigorous aerobic exercise five times per week, with at least three of the sessions being facility based. The control group was asked not to change their activity and both groups were asked not to change their diet.

Subjects:

A total of 320 postmenopausal, sedentary, normal weight-to-obese women aged 50–74 years who were cancer-free, nondiabetic and nonhormone replacement therapy users were included in this study.

Measurements:

Anthropometric measurements of height, weight and waist and hip circumferences; dual energy X-ray absorptiometry measurements of total body fat; and computerized tomography measurements of abdominal adiposity were carried out.

Results:

Women in the exercise group exercised a mean of 3.6 days (s.d.=1.3) per week and 178.5 min (s.d.=76.1) per week. Changes in all measures of adiposity favored exercisers relative to controls (P<0.001). The mean difference between groups was: −1.8 kg for body weight; −2.0 kg for total body fat; −14.9 cm² for intra-abdominal fat area; and −24.1 cm² for subcutaneous abdominal fat area. A linear trend of greater body fat loss with increasing volume of exercise was also observed.

Conclusion:

A 1-year aerobic exercise program consistent with current public health guidelines resulted in reduced adiposity levels in previously sedentary postmenopausal women at higher risk of breast cancer.

Noncompliance in lifestyle intervention studies: the instrumental variable method provides insight into the bias

OBJECTIVE

In lifestyle intervention trials, participants of the control group often change their behavior despite the request to maintain their usual lifestyle pattern. These changes in the control group and changes in addition to the intended in the intervention group can lead to undesirable confounding effects.

STUDY DESIGN AND SETTING

We address several considerations for study design to prevent noncompliance or minimize its effects. Furthermore, we demonstrate how the instrumental variable method can give insight into the extent of bias introduced by noncompliance in randomized trials, within the context of the Sex Hormones and Physical Exercise study.

RESULTS

Noncompliance can be prevented by measures taken in the design phase of a study, for example, limited duration of the study, clear recommendations, power calculation, intensity of the intervention, involvement of the control group, waiting-list control group, and single-consent design nested within an observational study. When nevertheless noncompliance does occur, the instrumental variable method estimates the intervention effect of treatment among the compliers.

CONCLUSION

Noncompliance can seriously affect validity of lifestyle trial results. Its occurrence should be prevented by taking measures during the design phase of a study. The instrumental variable method can give insight into confounding by noncompliance in randomized trials.

Ethnic differences in the relationships of anthropometric measures to metabolic risk factors in Asian patients at risk of atherothrombosis: results from the REduction of Atherothrombosis for Continued Health (REACH) Registry

The aim of the study is to examine the relationships between 4 anthropometric indices and metabolic risk factors (hypertension, atherogenic dyslipidemia, and glucose intolerance) in different Asian ethnic groups of patients at risk of atherothrombosis. We analyzed the baseline data of 11 017 Asian patients with established atherothrombotic cardiovascular diseases or at least 3 atherothrombotic risk factors. In East and South Asians, the graded relationships of body mass index (BMI) with the presence of at least 2 metabolic risk factors remained significant after adjustment for waist circumference (top vs bottom quartile--East Asians: odds ratio, 2.02; 95% confidence interval, 1.67-2.45; South Asians: 3.24, 1.18-8.95), whereas the graded relationships of waist circumference decreased or became nonsignificant after adjustment for BMI (East Asians: 1.64, 1.35-1.99; South Asians: 0.68, 0.20-2.30). In Southeast Asian men, the graded relationship of waist circumference with metabolic risk factors (2.27, 1.42-3.63) was stronger than that of BMI (1.34, 0.84-2.12), whereas in Southeast Asian women, there was a trend toward a stronger association between BMI and metabolic risk factors. In East Asians and in Southeast Asian women, the waist-to-BMI ratio decreased with the number of metabolic risk factors. The optimal cutoff points for BMI and waist circumference with regard to the presence of at least 2 metabolic risk factors were lowest in East Asians (men: 24 kg/m(2) and 86 cm; women: 24 kg/m(2) and 82 cm). Our findings suggest that both BMI and waist circumference, rather than waist circumference alone, should be included in metabolic risk assessment in this high-risk multiethnic Asian population. Uniform anthropometric cutoff values for all Asian ethnic groups are not appropriate to assess obesity-related metabolic complications, even in patients with established atherothrombotic disease.

Physical activity and breast cancer: review of the epidemiologic evidence and biologic mechanisms

Breast cancer is the most commonly diagnosed invasive malignancy and the second leading cause of cancer death in women globally. This review considers epidemiologic evidence regarding the association between physical activity and breast cancer risk. Across these studies there was a 25% average risk reduction among physically active women as compared to the least active women. The associations were strongest for recreational activity, for activity sustained over the lifetime or done after menopause, and for activity that is of moderate to vigorous intensity and performed regularly. There is also some evidence for a stronger effect of physical activity among postmenopausal women, women who are normal weight, have no family history of breast cancer, and are parous. It is likely that physical activity is associated with decreased breast cancer risk via multiple interrelated biologic pathways that may involve adiposity, sex hormones, insulin resistance, adipokines, and chronic inflammation. Future research should include prospective observational epidemiologic studies relating proposed biomarkers to breast cancer risk and also randomized controlled trials to examine how physical activity influences the proposed biomarkers. Exercise trials will provide more clarity regarding the appropriate type, dose, and timing of activity that are related to breast cancer risk reduction.Breast cancer remains a leading cause of cancer incidence and mortality in most developed countries worldwide. While significant international research has examined risk factors for breast cancer, most identified risk factors are nonmodifiable. During the past 20 years, over 90 studies have been conducted worldwide that have examined some aspects of the association between physical activity and breast cancer risk reduction. The purpose of this chapter is to review both the epidemiologic evidence and hypothesized biologic mechanisms whereby physical activity may influence breast cancer risk.