Physical Activity Related Variables Research Articles

The Relationship between Physical Activity Level and Sociodemographic Factors in Romanian Adults in the Post-COVID-19 Pandemic Period

Background: This study examines how socio-demographic factors relate to post-pandemic physical activity patterns among Romanian adults. Methods: A cross-sectional study explores post-COVID-19 physical activity levels (PAL) and their correlation with socio-demographic factors in Romanian adults (n = 237, average age 28.23 ± 9.91 years). An online questionnaire covering constitutional, socio-demographic, and physical activity-related variables was administered for data collection. Data analysis involves descriptive and inferential statistics, including Kendall’s tau correlation, along with multinomial regression analyses. Results: Noteworthy correlations emerged, including a robust association (r = 0.79, p < 0.001) between testing and history of clinical signs of COVID-19; a significant moderate correlation between health status and PAL compared to the period before the pandemic (τ = 0.56, p < 0.001); and significant moderate correlation between health status and current PAL (τ = −0.51, p < 0.001). Multinomial regression underscores an intricate relationship; testing for COVID-19 relates to clinical sign severity, health status changes influence post-pandemic PAL, and self-perceived health associates with current PAL (p < 0.001). Conclusions: Revealing significant links between PAL and socio-demographic factors among adults in Romania’s post-pandemic landscape, this study emphasizes the interaction between health changes and activity involvement. It also highlights the potential to guide interventions for rehabilitation and healthier living.

Multiple imputation approaches for epoch-level accelerometer data in trials.

Clinical trials that investigate physical activity interventions often use accelerometers to measure step count at a very granular level, for example in 5-second epochs. Participants typically wear the accelerometer for a week-long period at baseline, and for one or more week-long follow-up periods after the intervention. The data is aggregated to provide daily or weekly step counts for the primary analysis. Missing data are common as participants may not wear the device as per protocol. Approaches to handling missing data in the literature have defined missingness on the day level using a threshold on daily weartime, which leads to loss of information on the time of day when data are missing. We propose an approach to identifying and classifying missingness at the finer epoch-level and present two approaches to handling missingness using multiple imputation. Firstly, we present a parametric approach which accounts for the number of missing epochs per day. Secondly, we describe a non-parametric approach where missing periods during the day are replaced by donor data from the same person where possible, or data from a different person who is matched on demographic and physical activity-related variables. Our simulation studies show that the non-parametric approach leads to estimates of the effect of treatment that are least biased while maintaining small standard errors. We illustrate the application of these different multiple imputation strategies to the analysis of the 2017 PACE-UP trial. The proposed framework is likely to be applicable to other digital health outcomes and to other wearable devices.

Providing office workers with height-adjustable workstation to reduce and interrupt workplace sitting time: protocol for the Stand Up for Healthy Aging (SUFHA) cluster randomized controlled trial

BackgroundSedentary behavior (SB) has been linked to several negative health outcomes. Therefore, reducing SB or breaking up prolonged periods of SB improves functional fitness, food consumption, job satisfaction, and productivity. Reducing SB can be achieved by introducing a health-enhancing contextual modification promoted by a sit-stand desk in the workplace. The primary goal will be to test the effectiveness of this intervention in reducing and breaking up SB, while improving health outcomes in office-based workers during a 6-month intervention.MethodsA two-arm (1:1), superiority parallel-group cluster RCT will be conducted to evaluate the effectiveness of this intervention in a sample of office-based workers from a university in Portugal. The intervention will consist of a psychoeducation session, motivational prompts, and contextual modification promoted by a sit-stand desk in the workplace for 6 months. The control group will work as usual in their workplace, with no contextual change or prompts during the 6-month intervention. Three assessment points will be conducted in both groups, pre-intervention (baseline), post-intervention, and a 3-month follow-up. The primary outcomes include sedentary and physical activity-related variables, which will be objectively assessed with 24 h monitoring using the ActivPAL for 7 days. The secondary outcomes include (a) biometric indices as body composition, body mass index, waist circumference, and postural inequalities; and (b) psychosocial variables such as overall and work-related fatigue, overall discomfort, life/work satisfaction, quality of life, and eating behavior. Both the primary and secondary outcomes will be assessed at each assessment point.DiscussionThis study will lean on the use of a sit-stand workstation for 6 months, prompted by an initial psychoeducational session and ongoing motivational prompts. We will aim to contribute to this topic by providing robust data on alternating sitting and standing postures in the workplace.Trial registrationThe trial was prospectively registered, and the details are at: https://doi.org/10.17605/OSF.IO/JHGPW; Registered 15 November 2022. OSF Preregistration.

MHealth Interventions to Promote Physical Activity of Adults in Korea: Health Equity-Focused Systematic Review

Objectives: This study systematically review the existing literatures to identify the effectiveness of physical activity promotion programs using mobile health (mHealth) among Korean adults, with a focus on factors affecting health equity.Methods: To search for studies published in the past 10 years (from January 2013 to April 2023), Korean DBs (KoreaMed, KMBASE, KISS, RISS) were used. Hedge’g values were calculated to present uniform quantitative effect estimates for each study and to present pooled effect sizes for the same variables. Additionally, GRADE was used to assess the certainty of evidence and the review was conducted using the PROGRESS-Plus framework for health equity review.Results: Of the 1,204 literatures, 15 literatures were selected. Six prevention-based mHealth interventions and nine management-based mHealth interventions had significant effect sizes on multiple physical activity-related variables. A review of the PROGRESS-Plus factors revealed that personal characteristics (age, illness), occupation, and gender were the most frequently considered factors affecting health equity, while race, ethnicity, culture, language, religion, features of relationships , and time-dependent relationships were not considered.Conclusions: The results of the current study confirm the potential of mHealth-enabled physical activity promotion interventions to manage health and prevent disease in Korean adults. It also highlights the need to consider health equity in all phases of research design, implementation, and evaluation to provide opportunities for inclusive participation of a broad range of populations.

Students’ need satisfaction and frustration profiles: Differences in outcomes in physical education and physical activity-related variables

Grounded in self-determination theory, the objectives of the present research were to identify latent profiles based on need-based experiences in physical education (PE), and to examine differences in outcomes in PE (i.e. motivation, experiences, and oppositional defiance) and outside of PE (i.e. physical activity intention, moderate-to-vigorous physical activity, and meeting physical activity recommendations) across the identified profiles. A purposive sample of 1062 secondary PE students (526 boys and 536 girls; Mage = 14.15, SD = 1.51) participated in this cross-sectional study. Results from latent profile analysis revealed four need satisfaction and frustration profiles: “high need satisfaction–low need frustration”; “moderate need satisfaction–low need frustration”; “moderate need satisfaction–moderate need frustration”; and “low need satisfaction–high need frustration.” For outcomes in PE, the “high need satisfaction–low need frustration” profile was the most adaptive, while the “low need satisfaction–high need frustration” profile obtained the most maladaptive pattern of outcomes. The “moderate need satisfaction–low need frustration” profile was more adaptive than the “moderate need satisfaction–moderate need frustration” profile, although both were similar in experiences and oppositional defiance. For outcomes outside of PE, the “high need satisfaction–low need frustration” profile scored highest, while no differences were obtained among the three remaining profiles. These results provide further insight into the importance for PE teachers not only to support students’ need satisfaction, but also to minimize need frustration, in obtaining the most optimal pattern of outcomes in PE, as well as a more active lifestyle among students.

Factors associated with changes in the objectively measured physical activity among Japanese adults: A longitudinal and dynamic panel data analysis.

Factors associated with dynamic changes in the objectively measured physical activity have not been well understood. We aimed to 1) evaluate the longitudinal change in the physical activity trajectory according to sex which is associated with age and to 2) determine the factors associated with the dynamic change in physical activity-related variables across a wide age range among Japanese adults. This longitudinal prospective study included 689 Japanese adults (3914 measurements) aged 26-85 years, whose physical activity data in at least two surveys were available. Physical activity-related variables, such as intensity (inactive, light [LPA; 1.5 to 2.9 metabolic equivalents (METs)], moderate-to-vigorous [MVPA; ≥3.0 METs]), total energy expenditure (TEE), physical activity level (PAL), and step count, were evaluated using a validated triaxial accelerometer. Statistical analysis involved the latent growth curve models and random-effect panel data multivariate regression analysis. During a mean follow-up period of 6.8 years, physical activity was assessed an average of 5.1 times in men and 5.9 times in women. The profiles for the inactive time, LPA (only men), MVPA, step count, PAL, and TEE showed clear curvature, indicating an accelerated rate of change around the age of 70. In contrast, other variables exhibited minimal or no curvature over the age span. The MVPA trajectory was positively associated with alcohol consumption, hand grips, leg power, and trunk flexibility and negatively associated with age, local area, body mass index (BMI), comorbidity score, and heart rate over time. Our results indicated that the physical activity trajectory revealed clear curvature, accelerated rate of change around the age of 70, and determined physical health and fitness and BMI as dynamic factors associated with physical activity changes. These findings may be useful to help support populations to achieve and maintain the recommended level of physical activity.

Parental Support and Concerns About Physical Activities of Their Children with Autism Spectrum Disorder During COVID-19

Parental support is one of the intertwining factors that affect physical activity (PA) in children with autism spectrum disorder (ASD). With multiple COVID-19 regulations that have posed many challenges for people participating in their usual social activities, including PA, there is a need to examine parent concerns and support behaviors for PA of children with ASD. Thus, the purpose of this study was to investigate how the PA support behaviors of parents of children with ASD and COVID-19 concerns about their children’s PA participation changed during the pandemic and how these variables are correlated with other variables, such as their children’s demographic and PA related variables. Parents (n = 253) of children with ASD aged 10–17 years old completed an online survey that queried their children’s demographic information, parent PA support behaviors, parent and child PA, COVID-19 concerns about their children’s PA participation, and the perceived importance of their children’s PA. The results showed that parents’ COVID-19 concerns for their children participating in PA significantly correlated to the severity of their children’s ASD. Parents who identified as more physically active and perceived their children’s PA participation as more important tended to show higher COVID-19-related concerns. In addition, higher COVID-19 concerns among parents negatively correlated with their children’s PA variables. Parent PA support behaviors showed a significant reduction during the pandemic compared to before the pandemic. Overall, the findings suggest that it is important to provide parents with information on safe PA participation and resources to promote their children’s PA.

Impact of the COVID-19 pandemic on BMI: Its changes in relation to socio-demographic and physical activity patterns based on a short period.

BackgroundThe COVID-19 pandemic is undoubtedly a major threat to the world. The preventive strategies designed to minimize the virus transmission by remaining at home, being isolated, and keeping social distance, which would substantially reform people’s lifestyle, physical activity, eating habits, etc. Consequently, those measures might create a disturbance in weight management and overweight. Therefore, how the COVID-19 pandemic has changed the physical activities of individuals and its impacts on the Body Mass Index (BMI) is explored herein.MethodsAn online-based cross-sectional study collected data from 338 Bangladeshi adults in November 2020. The questionnaire included socio-demographics, health-related variables, physical activity-related variables, and diet measurement. Inferential statistics (i.e., chi-square test, McNemar test) were used to measure the associations between BMI and studied variables with a consideration of two scenarios (‘before’ and ‘during’ the pandemic inception), where p<0.05 was considered statistically significant.ResultsResults showed that the prevalence of overweight was 30.5% ‘before’ the COVID-19 pandemic, which increased to 34.9% ‘during’ the pandemic; that means 4.4% of the participants significantly gained weight after the pandemic inception. There was no significant role of socio-demographic (e.g., gender, age, current residence, occupation) or physical activity-related factors (e.g., unavailability of outdoor space, not performing regular physical exercise, exercising with a partner) in changing the BMI status after the pandemic inception. However, following a proper diet plan during the COVID-19 pandemic was observed to decrease BMI status significantly.ConclusionsThe present study suggests that a minor portion of the participants reported increasing their overweight status after the pandemic inception, whereas having a proper diet plan during the pandemic can significantly decrease BMI status. Therefore, the importance of the appropriate diet plan should be considered while implementing any policies.

The FTO rs17817449 Polymorphism is Not Associated With Sedentary Time, Physical Activity, or Cardiorespiratory Fitness: Findings From the GENADIO Cross-Sectional Study.

Genetic variants within the FTO gene have been associated with increased adiposity and metabolic markers; however, there is limited evidence regarding the association of FTO gene variants with physical activity-related variables. The authors aimed to investigate the association of the rs17817449 single-nucleotide polymorphism of FTO with physical activity, sedentary time, and cardiorespiratory fitness in Chilean adults. A total of 409 participants from the GENADIO study were included and genotyped for the rs17817449 single-nucleotide polymorphism of FTO in this cross-sectional study. Physical activity and sedentary time were measured with ActiGraph accelerometers. Cardiorespiratory fitness was assessed using the Chester step test. The associations were assessed by using multivariate regression analyses. No associations were found for FTO variant with physical activity levels and cardiorespiratory fitness. The risk allele (G) of the FTO was found to be associated with sedentary time in the minimally adjusted model (β = 19.7min/d; 95% confidence interval, 4.0 to 35.5, per each copy of the risk allele; P = .006), but the association was no longer significant when body mass index was included as a confounder (P = .211). The rs17817449 single-nucleotide polymorphism of the FTO gene was not associated with the level of physical activity, cardiorespiratory fitness, and sedentary behaviors in Chilean adults.

Description and comparison of physical activity from self-reports and accelerometry among primary school children in Kilimanjaro, Tanzania: a pilot study.

Background: Self-reports are commonly used to assess physical activity in children. Existing self-reports for physical activity have not been validated for primary school children in Tanzania. To understand if primary school children can accurately report their physical activity, we examined the validity of self-reported physical activity against accelerometer measured physical activity. Methods: A community-based cross-sectional study was conducted from May to July 2018. We conveniently selected four primary schools in Moshi municipal and Moshi rural districts in Kilimanjaro, Tanzania. From these districts, 51 children aged 9 - 11 years were randomly selected. A self-reported questionnaire was used to collect physical activity-related variables. Children wore accelerometers for seven consecutive days to capture physical activity movements. Spearman's rank test and Bland Altman plots were used for assessing validity and agreement between self-reports and accelerometer moderate to vigorous physical activity (MVPA). Results: The study participants' mean age was 10 (SD=0.8) years, and 32 (63%) were girls. A significant positive correlation was found between self-reports and accelerometer MVPA (rho=0.36, p=0.009). The mean total of weekday minutes in MVPA from accelerometers was higher than from self-reports, 408 (SD = 66) versus 261 (SD = 179). Conclusions: This study found a significant positive correlation between self-reports and accelerometers. Self-reports are prone to errors due to recall bias, which interferes with their validity. More research is needed to develop better self-reported measures with specific activities that children can easily remember. Also, researchers should carefully consider the inherent limitations in the validity of self-reports.

Description and comparison of physical activity from self-reports and accelerometry among primary school children in Kilimanjaro, Tanzania: a pilot study

Background: Self-reports are commonly used to assess physical activity in children. Existing self-reports for physical activity have not been validated for primary school children in Tanzania. To understand if primary school children can accurately report their physical activity, we examined the validity of self-reported physical activity against accelerometer measured physical activity. Methods: A community-based cross-sectional study was conducted from May to July 2018. We conveniently selected four primary schools in Moshi municipal and Moshi rural districts in Kilimanjaro, Tanzania. From these districts, 51 children aged 9 – 11 years were randomly selected. A self-reported questionnaire was used to collect physical activity-related variables. Children wore accelerometers for seven consecutive days to capture physical activity movements. Spearman’s rank test and Bland Altman plots were used for assessing validity and agreement between self-reports and accelerometer moderate to vigorous physical activity (MVPA). Results: The study participants' mean age was 10 (SD=0.8) years, and 32 (63%) were girls. A significant positive correlation was found between self-reports and accelerometer MVPA (rho=0.36, p=0.009). The mean total of weekday minutes in MVPA from accelerometers was higher than from self-reports, 408 (SD = 66) versus 261 (SD = 179). Conclusions: This study found a significant positive correlation between self-reports and accelerometers. Self-reports are prone to errors due to recall bias, which interferes with their validity. More research is needed to develop better self-reported measures with specific activities that children can easily remember. Also, researchers should carefully consider the inherent limitations in the validity of self-reports.

Description and comparison of physical activity from self-reports and accelerometry among primary school children in Kilimanjaro, Tanzania: a pilot study

Background: Self-reports are commonly used to assess physical activity in children. Existing self-reports for physical activity have not been validated for use among primary school children in, Tanzania. In order to understand if primary school children can accurately report their physical activity, we examined the validity of self-reported physical activity against accelerometer measured physical activity. Methods: A community based cross-sectional study was conducted from May to July, 2018. Four primary schools were conveniently selected in Moshi municipal and Moshi rural districts in Kilimanjaro, Tanzania and from these 51 children aged 9 – 11 years were randomly selected. Self-reported questionnaire was used to collect physical activity related variables. In addition, children wore accelerometers for seven consecutive days to capture physical activity movements. Spearman’s rank test and Bland Altman plots were used for assessing validity and agreement between self-reports and accelerometer moderate to vigorous physical activity (MVPA). Results: The mean age of the study participants was 10 (SD=0.8) years and 32 (63%) were girls. A positive significant correlation was found between self-reports and accelerometer MVPA (rho=0.36, p=0.009). Accelerometer had higher mean MVPA 408 (SD = 66) compared to self-reports 261 (SD = 179). Children who reported walking to school had higher MVPA for both accelerometer and self- reports compared to children who use other means of transport to school, e.g. school buses (p &lt; 0.001). Conclusions: This study found a positive significant correlation between self-reports and accelerometers. Self-reports are prone to errors due to recall bias, and this interferes their validity. More research is needed to develop better self-reported measures with specific activities which can easily be recalled by children. Also, researchers have to be aware of self-reports validity limitation.

Description and comparison of physical activity from self-reports and accelerometry among primary school children in Kilimanjaro, Tanzania: a pilot study

Background: Self-reports are commonly used to assess physical activity in children. Existing self-reports for physical activity have not been validated for primary school children in Tanzania. To understand if primary school children can accurately report their physical activity, we examined the validity of self-reported physical activity against accelerometer measured physical activity. Methods: A community-based cross-sectional study was conducted from May to July 2018. We conveniently selected four primary schools in Moshi municipal and Moshi rural districts in Kilimanjaro, Tanzania. From these districts, 51 children aged 9 – 11 years were randomly selected. A self-reported questionnaire was used to collect physical activity-related variables. Children wore accelerometers for seven consecutive days to capture physical activity movements. Spearman’s rank test and Bland Altman plots were used for assessing validity and agreement between self-reports and accelerometer moderate to vigorous physical activity (MVPA). Results: The study participants' mean age was 10 (SD=0.8) years, and 32 (63%) were girls. A significant positive correlation was found between self-reports and accelerometer MVPA (rho=0.36, p=0.009). The mean total of weekday minutes in MVPA from accelerometers was higher than from self-reports, 408 (SD = 66) versus 261 (SD = 179). Conclusions: This study found a significant positive correlation between self-reports and accelerometers. Self-reports are prone to errors due to recall bias, which interferes with their validity. More research is needed to develop better self-reported measures with specific activities that children can easily remember. Also, researchers should carefully consider the inherent limitations in the validity of self-reports.

Validation of self-reported physical activity by accelerometry among primary school children in Kilimanjaro, Tanzania: a pilot study

Background: Self-reports are commonly used to assess physical activity in children. Existing self-reports for physical activity have not been validated for use among primary school children in Kilimanjaro, Tanzania. In order to understand if primary school children can accurately report their physical activity, we examined the validity of self-reported physical activity against accelerometer measured physical activity. Methods: A community based cross-sectional study was conducted from May to July, 2018 among four primary schools in Moshi municipal and Moshi rural districts, Kilimanjaro, Tanzania. A total of 51 primary school children aged 9-11 years were enrolled using a simple random sampling technique. A self-reported questionnaire was used to collect physical activity related variables. In addition, children wore accelerometers for seven consecutive days to capture physical activity movements. Spearman's rank test and Bland Altman plots were used for assessing validity and agreement between self-reports and accelerometer moderate to vigorous physical activity (MVPA). Results: The mean age of the study participants was 10 (SD=0.8) years. Majority of the study participants were female 32 (63%). A moderate, positive correlation was found between self-reports and accelerometer MVPA (rho=0.36, p=0.009). Accelerometer had higher MVPA compared to self-reports. Children who reported walking to school had higher MVPA for both accelerometer and self- reports compared to children who use other means of transport to school, e.g. school buses (p < 0.001). Conclusions: This study found the moderate positive correlation between self-reports and accelerometers. Self-reports are prone to errors due to recall bias, and this interferes their validity. More research is needed to develop better self-reported measures with specific activities which can easily be recalled by children. Also, researchers have to be aware of self-reports validity limitation.

Patterns of sun safety behaviors in parents: Associations with physical activity, sedentary behavior, and access to neighborhood physical activity resources

Exposure to ultraviolet rays is associated with increased risk of sunburn – a biomarker of skin cancer risk – and physical activity can increase exposure. Sun safety behaviors can mitigate the increased risk of skin cancer. The objective of this cross-sectional study was to determine associations between physical activity behaviors, access to neighborhood physical activity resources, and sunburn across different patterning of sun safety behaviors. Data collected in 2014 from parents in the United States were analyzed (N = 1680; 75% female, primarily between the ages of 35–44 and 45–59, and 67% White). Latent class analysis was conducted to identify classes of sun safety behaviors based on engagement in sun protective behaviors (wearing a hat, shirt with sleeves, and seeking shade) and sun exposure (tanning outdoors). The latent classes were then examined as moderators of the association between physical activity related variables and sunburn. Three classes were identified corresponding to Low, Moderate, and High Risk for sunburn. There was no evidence of moderation, so equality constraints were imposed across the classes. Moderate-to-vigorous physical activity (MVPA) (odds ratio [OR] = 1.09) and neighborhood environments favoring physical activity (OR = 1.39) were associated with an increased likelihood of sunburn. Greater engagement in physical activity and access to built environments that favour activity are associated with a higher likelihood of sunburn, regardless of sun safety behaviors. Physically active parents are a vulnerable population for melanoma, and cancer prevention efforts focused on physical activity should also address sun safety.

Changes in the physical activity of university students during the first three years of university

Introduction: physical inactivity is the fourth most important risk factor for mortality worldwide and university students present this risk factor at a high level. Objective: to determine the changes in the physical activity of university students in Navarra during the first three years of college. Methods: prospective observational study of a cohort of university students. They participated in the first year, and two years later in the third year. The cohorts were comprised of 454 students who answered a voluntary and anonymous self-completion questionnaire with sociodemographic and physical activity related variables. Data were analyzed with SPSS v21.0. Results: of the participants, 67.4% (n = 306) were women and 32.6% (n = 148) were men. In the first year, 61.6% of students performed more than 150 minutes of physical activity per week. This percentage increased by 2.7%. The frequency of physical activity at least three times a week increased 6.1%, reaching 30.5% of students. Conclusions: university does not play a significant role in the promotion of physical activity, finding minimal modifications. In the future, it would be convenient to consider the reasons that hinder physical activity and design programs according to current recommendations.

Cross-sectional association of the number of neighborhood facilities assessed using postal code with objectively measured physical activity: the Saku cohort study.

Objectives The aim of this study was to examine the association between the number of neighborhood facilities that were assessed according to postal code and objectively measured physical activity by using an accelerometer in community-dwelling Japanese people.Methods The participants included 1,274 Japanese people aged 30-84 years from the Saku cohort study. As neighborhood facilities related to physical activity, we extracted information regarding train stations, supermarkets/convenience stores, postal offices/banks, hospitals/clinics, public offices/community centers, cultural facilities/public children's houses, parks, and sports facilities by using each participant's postal code from the online version of the iTownPages directory published by Nippon Telegraph and Telephone Corporation (NTT) and the official homepage of the Saku City Government Office. We measured each participant's physical activity level using an accelerometer, and calculated the average daily step count and the average weekly period of moderate-to-vigorous intensity (≥3 metabolic equivalents of tasks [METs]) physical activity. The association between two selected physical activity-related variables and the numbers of eight types of neighborhood facilities were analyzed by multivariate logistic regression analysis for people aged 30-64 years and for those aged over 65 years.Results On multivariate logistic regression analysis, meeting the 23 METs h/week of moderate-to-vigorous intensity physical activity was significantly and positively associated with the number of supermarkets/convenience stores in the neighborhood in both age groups. In addition, meeting the desired daily step count outlined in the Japanese National Health Promotion guidelines was positively related to the number of postal offices/banks for people aged over 65 years.Conclusion The results of this study suggest that a sufficient number of neighborhood facilities (i.e., stores, banks, and postal offices) is closely associated with the promotion of physical activity.

Effects of physical activity on evolution of proximal femur structure in a younger elderly population

Introduction: For a fixed weight, a wider bone of standardised length is stiffer. But moving the cortices away from the centre of mass risks creating structural (elastic) instability, and hip fractures have been postulated to occur as a consequence of buckling of the thinned supero-lateral femoral neck cortex during a fall. We hypothesised that stereotyped physical activity (e.g., walking) may help conserve bending resistance (section modulus, Z) through redistribution of bone tissue, but it might be at the expense of supero-lateral cortical stability. Methods: Hip structural analysis (HSA) software applied to DXA scans was used to derive measurements of section modulus and distances of a cross-section's centre of mass from the supero-lateral cortical margin (lateral distance, in cm). DXA scans were obtained on 1361 men and women in the EPIC-Norfolk population-based prospective cohort study. Up to 4 repeat DXA scans were done in 8 years of follow-up. Weight, height and activities of daily living were assessed on each occasion. A detailed physical activity and lifestyle questionnaire was administered at baseline. The lateral distance was measured on three narrow cross-sections with good precision: narrow neck (NN, coefficient of variation 2.6%), intertrochanter (IT) and shaft (S). A linear mixed model was used to assess associations with predictors. Results: Ageing was associated with medial shifting of the centre of mass, so that lateral distance increased. Both greater weight and height were associated with greater lateral distance ( P < 0.0001). Among physical activity-related variables, walking/cycling for > 1 h/day ( P = 0.025), weekly time spent on moderate impact activity ( P = 0.003), forced expiratory volume in 1 s (NN and IT, P < 0.026) and lifetime physical activity (IT, P < 0.0001) were associated with higher lateral distance. However, after adjusting for these variables, activities of daily living scores (NN, P < 0.0001) and weekly time spent on low impact hip flexing activities were associated with shorter lateral distance ( P = 0.001). Greater baseline lateral distance was significantly associated with increased risk of subsequent hip fracture ( n = 26) in females ( P < 0.05, all regions) independently of age, height and bone mineral content. Conclusion: The age-related shift medially of the centre of mass of the femoral neck and trochanter may have adverse effects on fracture resistance in the event of a fall, so compromising the beneficial effects of walking on fitness, strength and risk of falling. The role of more diverse physical activity patterns in old age that impose loading on the supero-lateral cortex of the femur, involving for example hip flexion and stretching, needs investigation for their ability to correct this medial shifting of the centre of mass.

Dietary intake-, eating behavior-, and physical activity-related determinants of high body mass index in the 2003 Wellness IN the Rockies cross-sectional study

The primary objective of the study was to assess associations between high body mass index (BMI) and dietary intake-, eating behavior-, and physical activity-related variables using follow-up cross-sectional data from Wellness IN the Rockies. Study participants were 883 men and 1030 women, aged 18 to 96 years, recruited from 6 rural communities in Wyoming, Montana, and Idaho. All study participants completed a questionnaire that elicited sociodemographic information, self-reported height and weight, and data related to specific dietary intakes, eating-related behaviors, and physical activity behaviors and perceptions. Prevalence of overweight (defined as a BMI ≥25 kg/m 2) in the 2003 follow-up survey was 66% in men and 56% in women, lower than the 70% (men) and 59% (women) figures reported from the 2001 baseline survey. Probability of high BMI was positively associated with specific eating habits: ordering supersized portions, eating while doing another activity, consumption of diet soft drinks, and consumption of foods from fast-food restaurants. Physical activity-related variables associated with high BMI were less frequent physical activity and the perception of not getting as much exercise as needed. The relationship between diet soft drink consumption and overweight/obesity could be because of the propensity of individuals with high BMIs to choose these beverages over regular soft drinks as a means to reduce overall energy expenditures. The finding of a relationship between greater frequency of eating while doing another activity and high BMI in both the 2001 and 2003 surveys suggests that interventions aimed at reducing this eating-related behavior could be an effective strategy for helping individuals maintain healthy body weights.

Decline in physical activity, disability and pain-related fear in sub-acute low back pain

Aim of investigation: To evaluate whether a perceived decline in the level of physical activity after the onset of pain (PAD) is more appropriate in the explanation of disability as compared to the actual level of physical activity (PAL) in patients with sub-acute back pain. Methods: Patients with 4–7 weeks of non-specific low back pain (LBP) participated in this study. Their habitual physical activity level before the back pain started (H-PAL), their actual level of physical activity (PAL) and their perceived decline in the level of physical activity after the onset of pain (PAD) were assessed. The association between these physical activity related variables and perceived disability (QBPDS), fear of movement/(re)injury (TSK), pain catastrophizing (PCS) and pain intensity (VAS) was examined. The role of PAD as a mediator in the association between fear of movement/(re)injury and disability was examined by three linear regression analyses. Results: 123 patients (66 male and 57 female) with a mean age of 44.1 years (SD = 10.3) participated in this study. PAD was significantly correlated with disability, fear of movement/(re)injury, pain catastrophizing and pain intensity. PAD and PAL appeared more important in the explanation of disability in the subgroup of patients who were physically active before their back pain started. Generally, PAD indeed mediated the association between fear of movement/(re)injury and disability. Conclusions: The perceived decline in physical activity, rather than the current physical activity itself is important in the evaluation of the impact of activity related changes on disability in low back pain.