Physical Activity during Work,Transport and Leisure in Germany - Prevalence and Socio-Demographic Correlates

Background

This study aimed 1) to provide data estimates concerning overall moderate- and vigorous-intensity physical activity (MVPA) as well as MVPA during work, transport and leisure in Germany and 2) to investigate MVPA and possible associations with socio-demographic correlates.

Methods

A cross-sectional telephone survey interviewed 2248 representative participants in the age of 18–65 years (1077 men; 42.4±13.4 years; body mass index: 25.3±4.5kg•m⁻²) regarding their self-reported physical activity across Germany. The Global Physical Activity Questionnaire was applied to investigate MVPA during work, transport and leisure and questions were answered concerning their demographics. MVPA was stratified by gender, age, body mass index, residential setting, educational and income level. To identify socio-demographic correlates of overall MVPA as well as in the domains, we used a series of linear regressions.

Results

52.8% of the sample achieved physical activity recommendations (53.7% men/52.1% women). Overall MVPA was highest in the age group 18–29 years (p<.05), in participants with 10 years of education (p<.05) and in participants with lowest income levels <1.500€ (p<.05). Regression analyses revealed that age, education and income were negatively associated with overall and work MVPA. Residential setting and education was positively correlated with transport MVPA, whereas income level was negatively associated with transport MVPA. Education was the only correlate for leisure MVPA with a positive association.

Conclusions

The present data underlines the importance of a comprehensive view on physical activity engagement according to the different physical activity domains and discloses a need for future physical activity interventions that consider socio-demographic variables, residential setting as well as the physical activity domain in Germany.     

Objectively Measured Physical Activity in European Adults: Cross-Sectional Findings from the Food4Me Study

Background

Comparisons of objectively measured physical activity (PA) between residents of European countries measured concurrently with the same protocol are lacking. We aimed to compare PA between the seven European countries involved in the Food4Me Study, using accelerometer data collected remotely via the Internet.

Methods

Of the 1607 participants recruited, 1287 (539 men and 748 women) provided at least 3 weekdays and 2 weekend days of valid accelerometer data (TracmorD) at baseline and were included in the present analyses.

Results

Men were significantly more active than women (physical activity level = 1.74 vs. 1.70, p < 0.001). Time spent in light PA and moderate PA differed significantly between countries but only for women. Adherence to the World Health Organization recommendation to accumulate at least 150 min of moderate-equivalent PA weekly was similar between countries for men (range: 54–65%) but differed significantly between countries for women (range: 26–49%). Prevalence estimates decreased substantially for men and women in all seven countries when PA guidelines were defined as achieving 30 min of moderate and vigorous PA per day.

Conclusions

We were able to obtain valid accelerometer data in real time via the Internet from 80% of participants. Although our estimates are higher compared with data from Sweden, Norway, Portugal and the US, there is room for improvement in PA for all countries involved in the Food4Me Study.     

Obesity Is Associated With Altered Lung Function Independently of Physical Activity and Fitness

Measures of obesity, especially central adiposity, have been associated with reduced lung function. However, previous studies may have been affected by confounding by physical activity and fitness. This study aimed to examine the relationship among body fatness, fat distribution, and lung function, adjusted for physical activity energy expenditure (PAEE) and aerobic fitness (VO₂max), in a cohort of British white adults with a family history of type 2 diabetes. A total of 320 adults (mean age 40.4 ± 6.0 years) attended for anthropometric and VO₂max testing, and had ambulatory heart rate monitoring for 4 days to determine PAEE. Spirometry was used to measure forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC). The tests were repeated 12 months later, and a cross‐sectional analysis using linear regression with repeated measures was performed. Measures of obesity (BMI, waist circumference (WC), fat mass (FM), body fat percentage (BF%)) were associated with lower lung function in men and women (P < 0.01), while waist‐to‐hip ratio (WHR) was associated with lower lung function in men only (P < 0.001). Associations remained after adjusting for age, smoking status, height, PAEE, and VO₂max. The estimated difference in mean FEV₁ and FVC per unit increase in the exposure measures were consistently stronger in men compared to women (P for interaction <0.001). Obesity is inversely associated with lung function in adults, but central fat distribution appears to have a stronger relationship with respiratory mechanics in men than in women. These associations were independent of the degree of physical activity and aerobic fitness in this cohort.     

Safe To Walk? Neighborhood Safety and Physical Activity Among Public Housing Residents

Background

Despite its health benefits, physical inactivity is pervasive, particularly among those living in lower-income urban communities. In such settings, neighborhood safety may impact willingness to be regularly physically active. We examined the association of perceived neighborhood safety with pedometer-determined physical activity and physical activity self-efficacy.

Methods and Findings

Participants were 1,180 predominantly racial/ethnic minority adults recruited from 12 urban low-income housing complexes in metropolitan Boston. Participants completed a 5-d pedometer data-collection protocol and self-reported their perceptions of neighborhood safety and self-efficacy (i.e., confidence in the ability to be physically active). Gender-stratified bivariate and multivariable random effects models were estimated to account for within-site clustering. Most participants reported feeling safe during the day, while just over one-third (36%) felt safe at night. We found no association between daytime safety reports and physical activity among both men and women. There was also no association between night-time safety reports and physical activity among men (p = 0.23) but women who reported feeling unsafe (versus safe) at night showed significantly fewer steps per day (4,302 versus 5,178, p = 0.01). Perceiving one''s neighborhood as unsafe during the day was associated with significantly lower odds of having high physical activity self-efficacy among both men (OR 0.40, p = 0.01) and women (OR 0.68, p = 0.02).

Conclusions

Residing in a neighborhood that is perceived to be unsafe at night is a barrier to regular physical activity among individuals, especially women, living in urban low-income housing. Feeling unsafe may also diminish confidence in the ability to be more physically active. Both of these factors may limit the effectiveness of physical activity promotion strategies delivered in similar settings.     

The Associations of Objectively Measured Physical Activity and Sedentary Time with Cognitive Functions in School-Aged Children

Low levels of physical activity among children have raised concerns over the effects of a physically inactive lifestyle, not only on physical health but also on cognitive prerequisites of learning. This study examined how objectively measured and self-reported physical activity and sedentary behavior are associated with cognitive functions in school-aged children. The study population consisted of 224 children from five schools in the Jyväskylä school district in Finland (mean age 12.2 years; 56% girls), who participated in the study in the spring of 2011. Physical activity and sedentary time were measured objectively for seven consecutive days using the ActiGraph GT1M/GT3X accelerometer. Self-reported moderate to vigorous physical activity (MVPA) and screen time were evaluated with the questions used in the “WHO Health Behavior in School-aged Children” study. Cognitive functions including visual memory, executive functions and attention were evaluated with a computerized Cambridge Neuropsychological Test Automated Battery by using five different tests. Structural equation modeling was applied to examine how objectively measured and self-reported MVPA and sedentary behavior were associated with cognitive functions. High levels of objectively measured MVPA were associated with good performance in the reaction time test. High levels of objectively measured sedentary time were associated with good performance in the sustained attention test. Objectively measured MVPA and sedentary time were not associated with other measures of cognitive functions. High amount of self-reported computer/video game play was associated with weaker performance in working memory test, whereas high amount of computer use was associated with weaker performance in test measuring shifting and flexibility of attention. Self-reported physical activity and total screen time were not associated with any measures of cognitive functions. The results of the present study propose that physical activity may benefit attentional processes. However, excessive video game play and computer use may have unfavorable influence on cognitive functions.     

Leisure-Time Physical Activity and All-Cause Mortality

Background

Physical inactivity is a major public health problem associated with increased mortality risk. It is, however, poorly understood whether vigorous physical activity is more beneficial for reducing mortality risk than activities of lower intensity. The aim of this study was to examine associations of the intensity and volume of leisure-time physical activity with all-cause mortality among middle-aged women and men while considering sociodemographic and health related factors as covariates.

Methods

Questionnaire survey data collected in 2000-02 among 40–60-year-old employees of the City of Helsinki (N = 8960) were linked with register data on mortality (74% gave permission to the linkage) providing a mean follow-up time of 12-years. The analysis included 6429 respondents (79% women). The participants were classified into three groups according to intensity of physical activity: low moderate, high moderate and vigorous. The volume of physical activity was classified into three groups according to tertiles. Cox regression analysis was used to calculate hazard ratios (HR) and 95% confidence intervals (CIs) for all-cause mortality.

Results

During the follow up 205 participants died. Leisure-time physical activity was associated with reduced risk of mortality. After adjusting for covariates the vigorous group (HR = 0.54, 95% CI 0.34–0.86) showed a reduced risk of mortality compared with the low moderate group whereas for the high moderate group the reductions in mortality risk (HR = 0.72, 95% CI 0.48–1.08) were less clear. Adjusting for the volume of physical activity did not affect the point estimates. Higher volume of leisure-time physical activity was also associated with reduced mortality risk; however, adjusting for the covariates and the intensity of physical activity explained the differences.

Conclusions

For healthy middle-aged women and men who engage in some physical activity vigorous exercise may provide further health benefits preventing premature deaths.     

Levels and Patterns of Objectively Assessed Physical Activity and Compliance with Different Public Health Guidelines in University Students

Background

Physical activity (PA) is associated with health enhancement. The aim of this study was to assess: 1) levels and patterns of PA in university students by using accelerometers; and 2) the percentage of fulfilment of PA recommendations for adults, according to different public health guidelines.

Methods

Observational cross-sectional study (Cuenca’s Adults Study) involving 296 (206 women) healthy Spanish university students aged 18–25 years old. Participants wore the ActiGraph GT1M accelerometer for seven consecutive days. Total PA, steps and time spent in sedentary time, light, moderate, vigorous, and moderate to vigorous PA (MVPA) was assessed, and the prevalence of sufficient PA was calculated according to various public health guidelines.

Results

No sex differences in total PA were found. University students were more sedentary during weekend days than weekdays (p<0.05). Only 30.3% of participants accumulated 30 min/day at least five days a week of MVPA. A total of 5.4% of students met the recommendation of 150 min/week of MVPA or 75 min/week of vigorous PA, in PA bouts of at least 10 min. using the same definition, but on five or more days a week, only 0.5% students were found to meet the recommendation. In addition, only 0.5% of students met the recommendation of 30 min/day of MVPA, at least five days a week and in bouts of at least 10 min. Finally, 28.1% of the students met the recommendation of 10,000 steps/day.

Conclusions

Our study shows a high incidence of sedentary time in university students. The number of students meeting PA recommendations significantly differed depending on the recommendation proposed. Specific strategies to promote PA in this population are necessary as well as an agreement as to which PA guidelines should be used.     

Joint Association of Sitting Time and Physical Activity with Metabolic Risk Factors among Middle-Aged Malays in a Developing Country: A Cross-Sectional Study

Background

Prolonged sitting is associated with increased weight and higher risks for abdominal obesity, dyslipidaemia, hyperglycaemia and hypertension among the adult population. This has been well documented in the West, but studies on these associations are lacking in developing countries, including Malaysia.

Objective

This cross-sectional study aimed to examine the joint association of sitting time and physical activity with metabolic risk factors among middle-aged working adults.

Methodology

A total of 686 Malay men and women participated (mean age 45.9±6.5 years). Metabolic syndrome was diagnosed from the modified NCEP ATP III criteria. Self-reported sitting time was obtained with the validated Malay version of the International Physical Activity Questionnaire. Participants were asked about their time spent sitting during travel in a motor vehicle, e.g., car, motorcycle or bus, over the preceding 7 days. Logistic regression was used to estimate the odds ratio with the confidence interval for the combined effects of sitting quartiles and physical activity categories with metabolic risk factors.

Results/Significance

The prevalence of metabolic syndrome among our participants was 31.9%. Their average total sitting time (including transportation) was 7.6±2.4 h/day. After we adjusted for gender and educational level, higher sitting quartiles and physically inactive groups were associated with higher odds for metabolic syndrome compared with the referent group (sitting <6 h/day and physically active). In the physically active stratum, the odds for metabolic syndrome in participants who sat ≥9.3 h/day was 3.8 times that of participants who sat <6 h/day. Both higher sitting quartiles and insufficient physical activity were associated with adverse effects on abdominal obesity, hypertriglyceridemia and hyperglycaemia.

Conclusion

In joint analyses of sitting time and physical activity, higher sitting time and insufficient physical activity were deleteriously associated with odds for metabolic risk factors in middle-aged Malay men and women.     

Examining physical activity and inactivity in 9-12 years old children

Information about children's daily physical activity in Eastern-Europe is essential because of the increasing prevalence in overweight and obesity. Sixty-three children (age=11.16 ± 1.10 years; 33 boys and 30 girls) from two public elementary schools had their physical activity objectively measured using uni-axial accelerometer every 5 seconds for five consecutive days (3 weekdays, 2 weekend days). After data cleaning, 10 children were excluded from database. There were no significant differences in boys' and girls' BMI (17.6 ± 2.2 vs. 17.1 ± 2.4) and BF% (18.0 ± 5.2 vs. 19.4 ± 5.0). Children engaged in more sedentary, light, moderate, and vigorous physical activity and had higher counts per minute during weekdays compared to weekend days. There were no sex differences in moderate to vigorous physical activity (87.6 ± 22.4 vs. 93.5 ± 20.6 min and 53.6 ± 21.3 vs. 59.4 ± 22.0 min) during weekday and weekend days. Data indicated that 96% of the girls and 92% of the boys met the international physical activity guideline for children of 60 minutes of MVPA, on weekdays.     

Motivation and Barriers for Leisure-Time Physical Activity in Socioeconomically Disadvantaged Women

Introduction

The aim of this study was to examine cross-sectional and longitudinal associations between motivation and barriers for physical activity, and physical activity behavior in women living in socioeconomic disadvantage. This study also examined whether weight control intentions moderate those associations.

Methods

Data from 1664 women aged 18–46 years was collected at baseline and three-year follow-up as part of the Resilience for Eating and Activity Despite Inequality study. In mail-based surveys, women reported sociodemographic and neighborhood environmental characteristics, intrinsic motivation, goals and perceived family barriers to be active, weight control intentions and leisure-time physical activity (assessed through the IPAQ-L). Linear regression models assessed the association of intrinsic motivation, goals and barriers with physical activity at baseline and follow-up, adjusting for environmental characteristics and also physical activity at baseline (for longitudinal analyses), and the moderating effects of weight control intentions were examined.

Results

Intrinsic motivation and, to a lesser extent, appearance and relaxation goals for being physically active were consistently associated with leisure-time physical activity at baseline and follow-up. Perceived family barriers, health, fitness, weight and stress relief goals were associated with leisure-time physical activity only at baseline. Moderated regression analyses revealed that weight control intentions significantly moderated the association between weight goals and leisure-time physical activity at baseline (β = 0.538, 99% CI = 0.057, 0.990) and between intrinsic motivation and leisure-time physical activity at follow-up (β = 0.666, 99% CI = 0.188, 1.145). For women actively trying to control their weight, intrinsic motivation was significantly associated with leisure-time physical activity at follow-up (β = 0.184, 99% CI = 0.097, 0.313).

Conclusions

Results suggest that, especially in women trying to control their weight, intrinsic motivation plays an important role in sustaining physical activity participation over time. Also, weight goals for being physically active seem to play a role regarding short-term physical activity participation in this particular population. Addressing these motivational features may be important when promoting physical activity participation in women living in socioeconomically disadvantaged neighborhoods.     

Walking attenuates the relationships of high-meat, low-fruit dietary intake to total and regional adiposity in men and women

Vigorous physical activity (running) has been shown to attenuate the association between diet and body weight. Walking is the most popular physical activity, but is a moderate-intensity physical activity because it requires less than sixfold the energy expenditure of sitting at rest. We therefore examined whether reported distance walked per week affected the relationship of diet to BMI and circumferences of the waist, hip, and chest in 30,014 female and 7,133 male participants of the National Walkers' Health Study. Reported meat and fruit intakes served as indicators of high-risk diets for weight gain. The analyses showed that higher meat and lower fruit intake were significantly and consistently associated with greater BMI and waist circumference at all activity levels. Longer usual walking distance significantly attenuated the concordant relationships of diet with women's BMIs (P < 10(-8)), men's BMIs (P = 0.04), and women's waist (P < 10(-6)), hip (P = 0.0001), and chest circumferences (P < 10(-5)). Compared to walkers who averaged <1.5 km/day, the association of diet with adiposity in subjects who walked ≥1.5 km/day was reduced 21% in women and 31% in men for BMI; 20% in women and 27% in men for waist circumference; 19% for women's hip circumference; and 26% for women's chest circumference. Thus we conclude that diets characterized by high-meat/low-fruit intake were significantly associated with greater BMI, and this association was attenuated by moderate physical activity. The weaker results in men than women probably related to the smaller sample size, and reduced statistical power of the men.     

Work‐Related Physical Activity Is Not Associated with Body Mass Index and Obesity

Objective: To analyze the association of work‐related physical activity (WRPA) and leisure‐time physical activity (LTPA) with body mass index (BMI) and obesity in the Spanish adult population aged 20 to 60 years. Research Methods and Procedures: The data were taken from the 1993 Spanish National Health Survey. We analyzed a sample of 12,044 men and women representative of the Spanish population aged 20 to 60 years. BMI and frequency of obesity (BMI ≥ 30 kg/m²) were obtained from self‐reported weight and height. Multiple linear regression and logistic regression models were constructed, adjusting for the main confounding factors. WRPA and LTPA were measured by two questions to classify subjects into four categories of physical activity. Results: Neither mean BMI nor percentage of obesity varied significantly (p > 0.05) by WRPA. Mean BMI was significantly higher (p < 0.01) in those who were inactive in their leisure time (25.90 kg/m² in men and 24.43 kg/m² in women) than in those who reported vigorous activity (24.42 kg/m² and 22.97 kg/m² in men and women, respectively). The odds ration (OR) for obesity decreased with increasing level of LTPA in both men (OR of 0.64 for vigorous activity) and women (OR = 0.68), showing a statistically significant dose‐response relation in both men (for linear trend, p = 0.0021) and women (p = 0.0245). Discussion: These results raise questions about the association between WRPA and obesity and suggest the need to reexamine models of the obesity epidemic that point to automation of the workplace as one of the major explanatory factors.     

Leisure-time physical activity is associated with socio-economic status beyond income – Cross-sectional survey of the Northern Finland Birth Cohort 1966 study

We apply neoclassical economic modelling augmented with behavioral aspects to provide a detailed empirical investigation into indicators of socio-economic status (SES) as determinants of leisure-time physical activity. We utilize the data from the Northern Finland Birth Cohort 1966 obtained at the most recent time point during 2012–2014 (response rate 67 %), at which time the participants were approximately 46 years old. Our final study sample consists of 3,335 employed participants (1520 men, 1815 women; 32.3 % of the target population). We apply logistic regression methods for estimating how the probability of being physically active is related to various indicators of socio-economic status, taking into account physical activity at work and individual lifestyle, family- and health-related factors. Overall, our findings show that belonging to a higher socio-economic group, whether defined by income level, educational attainment, or occupational status, is associated with higher leisure-time physical activity. However, when we analyze different socio-economic groups, defined in terms of education, income and occupation, separately, we find that income is not a significant determinant of leisure-time physical activity within any of the particular SES groups. Further, we find that leisure-time physical activity is negatively associated with higher screen time (i.e., watching TV and sitting at a computer), and other aspects of unhealthy lifestyle, and positively associated with self-assessed health. In addition, we note that proxies for individual motivational factors and childhood physical activity, such as the grade point average and the grade achieved in physical education when leaving basic education, are strongly correlated with leisure-time physical activity in middle age among men, but not among women. Our results are in line with behavioral economics reasoning that social comparisons and environments affect behaviors. We emphasize the importance of considering behavioral economic factors when designing policies to promote physical activity.     

Physical activity, sedentary time, and pericardial fat in healthy older adults

Pericardial fat is emerging as a unique risk factor for coronary disease. We examined the relationship between objectively measured physical activity during free-living and pericardial fat. Participants were 446 healthy men and women (mean age = 66 ± 6 years), without history or objective signs of cardiovascular disease (CVD), drawn from the Whitehall II epidemiological cohort. Physical activity was objectively measured using accelerometers (Actigraph GT3X) worn around the hip during waking hours for 7 consecutive days (average daily wear time = 889 ± 68 min/day), and was classified as sedentary (<200 counts/min (cpm)), light (200-1,998 cpm), or moderate-vigorous physical activity (MVPA; ≥1,999 cpm). Pericardial fat volume was measured in each participant using electron beam computed tomography. Average daily cpm in men was 338.0 ± 145.0 and in women 303.8 ± 130.2. There was an inverse association between average cpm and pericardial fat (B = -0.070, 95% confidence interval (CI), -0.101, -0.040, P < 0.001), and this remained significant after adjusting for age, sex, registered wear time, BMI, lipids, glycemic control, blood pressure, smoking, statins, and social status. Both sedentary time (B = 0.081, 95% CI, 0.022, 0.14) and MVPA (B = -0.362, 95% CI, -0.527, -0.197) were also associated with pericardial fat, although associations for sedentary time did not remain significant after adjustment for MVPA. The inverse association between physical activity and pericardial fat was stronger among overweight and obese adults than in normal weight. Objectively assessed daily activity levels are related to pericardial fat in healthy participants, independently of BMI. This might be an important mechanism in explaining the association between physical activity and CVD prevention.     

Adult Active Transport in the Netherlands: An Analysis of Its Contribution to Physical Activity Requirements

Introduction

Modern, urban lifestyles have engineered physical activity out of everyday life and this presents a major threat to human health. The Netherlands is a world leader in active travel, particularly cycling, but little research has sought to quantify the cumulative amount of physical activity through everyday walking and cycling.

Methods

Using data collected as part of the Dutch National Travel Survey (2010 – 2012), this paper determines the degree to which Dutch walking and cycling contributes to meeting minimum level of physical activity of 150 minutes of moderate intensity aerobic activity throughout the week. The sample includes 74,465 individuals who recorded at least some travel on the day surveyed. As physical activity benefits are cumulative, all walking and cycling trips are analysed, including those to and from public transport. These trips are then converted into an established measure of physical activity intensity, known as metabolic equivalents of tasks. Multivariate Tobit regression models were performed on a range of socio-demographic, transport resources, urban form and meteorological characteristics.

Results

The results reveal that Dutch men and women participate in 24 and 28 minutes of daily physical activity through walking and cycling, which is 41% and 55% more than the minimum recommended level. It should be noted however that some 57% of the entire sample failed to record any walking or cycling, and an investigation of this particular group serves as an important topic of future research. Active transport was positively related with age, income, bicycle ownership, urban density and air temperature. Car ownership had a strong negative relationship with physically active travel.

Conclusion

The results of this analysis demonstrate the significance of active transport to counter the emerging issue of sedentary lifestyle disease. The Dutch experience provides other countries with a highly relevant case study in the creation of environments and cultures that support healthy, active living.     

Night work and mortality: prospective study among Finnish employees over the time span 1984 to 2008

There is considerable evidence showing that night work is associated with increased morbidity, but only a few studies have focused on its relation to mortality. This study investigates the relationship between the type of working-time arrangement (weekly night work/daytime work) and total and cause-specific mortality among men and women. The data consist of a representative working conditions survey of Finnish employees conducted in 1984 (2286 men/2216 women), which has been combined with register-based follow-up data from Statistics Finland covering the years 1985-2008. In the 1984 survey, the employees were asked if they worked during the night (23:00-06:00 h) and if so, how often. In this study, the authors compare employees who worked at night (121 men/89 women) to daytime employees who did not do night work (1325 men/1560 women). The relative risk of death was examined by Cox proportional hazards analyses adjusted for background (age, level of education, family situation, and county), health (longstanding illness, pain symptoms, smoking status, and psychological symptoms), and work-related factors (weekly working hours, physical and psychological demands, demands of learning at work, and perceived job insecurity). Female employees working at night had a 2.25-fold higher risk of mortality than female dayworkers (95% confidence interval [CI] 1.20-4.20) after adjustment for background and health- and work-related factors. In addition to total mortality, night work was also associated with tumor mortality. Female night workers had a 2.82-fold higher risk of tumor mortality than female dayworkers (95% CI 1.20-6.65) in the adjusted model. Among men, no such significant association was observed. The present study indicated that female night workers had a higher risk of both total and tumor mortality compared to female daytime employees. Additional research on the potential factors and mechanisms behind the association between night work and mortality is required.     

Pedometer-determined physical activity and indicators of health in Japanese adults

Recently, many cross-sectional studies observed that body mass index (BMI) and percentage of body fat (%BF) were inversely associated with pedometer-determined physical activities, but studies on Asian populations, including the Japanese, are sparse. Height, weight, body fat percentage (%BF, bioelectrical impedance analyzer), and waist circumference were measured on 117 women (62.8+/-4.5 years, 22.2+/-2.2 kg/m(2)) and 62 men (64.0+/-4.6 years, 23.6+/-2.5 kg/m(2)). Pearson correlations and partial correlation coefficients after controlling for age were calculated between steps/day and variables. Furthermore, participants were classified into four groups as follows: <5,000, 5,000-7,499, 7,500-9,999, and >or=10,000 steps/day, and analyzed using ANOVA across activity groups. In women, a significant correlation was found between steps/day and BMI (r=-0.217, p=0.018), %BF (r=-0.292, p=0.0014), and the relationship was still significant after controlling for age. The relationship between steps/day and waist circumference was not significant. In men, a significant relationship was not observed between steps/day and obesity indices. The correlations between steps/day and both BMI and %BF were significant in Japanese women, but weak compared with Caucasian and African-American women as reported previously. A possible cause is racial difference in degree of obesity and body shape. The effects of physical activity on body shape and composition may differ according to race.     

Physical activity and risk of rheumatoid arthritis in women: a population-based prospective study

IntroductionOnly one study has analysed the association between exercise and development of rheumatoid arthritis (RA), showing no association. Aim of this paper was to evaluate the association of physical activity in all its aspect with RA.MethodsTo examine this association, middle age and elderly women from the Swedish Mammography Cohort, a population-based prospective study, were analysed. Data on physical activity were collected in 1997 by self-administrated food-frequency questionnaire. Risk of RA associated with physical activity was estimated using Cox proportional hazard regression models.ResultsAmong 30,112 women born between 1914 and 1948 followed-up from January 1, 2003 to December 31, 2010, 201 RA cases were identified (226,477 person-years). There was a statistically significant 35% lower risk of RA (relative risk (RR), 0.65; 95% confidence interval (CI), 0.43-0.96) among women in the highest category of leisure-time activity (combining more than 20 minute per day of walking/bicycling (median 40–60 minute per day) and more than 1 hour per week of exercise (median 2–3 hours per week)) as compared to women in the lowest category (less than 20 minute per day of walking/bicycling and less than 1 hour per week of exercise). A non-statistically significant decreased risk was observed for household work (−32%) and work/occupation (−15%), while an increased risk was observed for leisure-time physical inactivity (+27%). Daily energy expenditure was not associated with risk of RA.ConclusionsThis prospective population-based cohort study of women supports the hypothesis that physical activity can be a protective factor in the etiology of rheumatoid arthritis. Our results add to accumulated evidence on benefits of modifiable leisure-time physical activity for prevention of many other chronic diseases.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0560-2) contains supplementary material, which is available to authorized users.     

Comparison of Self-Reported and Accelerometer-Assessed Physical Activity in Older Women

Background

Self-reported physical activity measures continue to be validated against accelerometers; however, the absence of standardized, accelerometer moderate-to-vigorous physical activity (MVPA) definitions has made comparisons across studies difficult. Furthermore, recent accelerometer models assess accelerations in three axes, instead of only the vertical axis, but validation studies have yet to take incorporate triaxial data.

Methods

Participants (n = 10 115) from the Women’s Health Study wore a hip-worn accelerometer (ActiGraph GT3X+) for seven days during waking hours (2011–2014). Women then completed a physical activity questionnaire. We compared self-reported with accelerometer-assessed MVPA, using four established cutpoints for MVPA: three using only vertical axis data (760, 1041 and 1952 counts per minute (cpm)) and one using triaxial data (2690 cpm).

Results

According to self-reported physical activity, 66.6% of women met the US federal physical activity guidelines, engaging in ≥150 minutes per week of MVPA. The percent of women who met guidelines varied widely depending on the accelerometer MVPA definition (760 cpm: 50.0%, 1041 cpm: 33.0%, 1952 cpm: 13.4%, and 2690 cpm: 19.3%).

Conclusions

Triaxial count data do not substantially reduce the difference between self-reported and accelerometer-assessed MVPA.