Editorial for special issue: Advances in sedentary behavior research and translation

Sedentary behaviour—essentially low energy sitting time in waking hours—has emerged as an important topic in public health over the past decade or so. Although Morris and colleagues [1] analysed health outcomes of active versus seated occupations over 60 years ago, it was not until studies of TV viewing in children in the 1980s [2] that researchers started to recognise “too much sitting” as a potentially important health behaviour. Even then the rapid rise in the study of sedentary behaviour was not so evident until the early 2000s [3]–[5]. Studies on screen viewing (TV and computers), sitting at work and school, and sitting in cars have all emerged over this period, as well as a general recognition that high levels of sitting may have detrimental effects on health, and possibly be independent of levels of moderate-to-vigorous physical activity (MVPA). In the past 10–15 years there has been an exponential increase in papers addressing sedentary behaviour from the perspective of sitting, noting that many exercise physiologists still use the word 'sedentary' incorrectly by referring to those not meeting a criterion level of “sufficient” physical activity

Unaccustomed eccentric contractions impair plasma K+ regulation in the absence of changes in muscle Na+,K+-ATPase content

The Na+,K+-ATPase (NKA) plays a fundamental role in the regulation of skeletal muscle membrane Na+ and K+ gradients, excitability and fatigue during repeated intense contractions. Many studies have investigated the effects of acute concentric exercise on K+ regulation and skeletal muscle NKA, but almost nothing is known about the effects of repeated eccentric contractions. We therefore investigated the effects of unaccustomed maximal eccentric knee extensor contractions on K+ regulation during exercise, peak knee extensor muscle torque, and vastus lateralis muscle NKA content and 3-O-MFPase activity. Torque measurements, muscle biopsies, and venous blood samples were taken before, during and up to 7 days following the contractions in six healthy adults. Eccentric contractions reduced peak isometric muscle torque immediately post-exercise by 26±11% and serum creatine kinase concentration peaked 24 h post-exercise at 339±90 IU/L. During eccentric contractions, plasma [K+] rose during Set 1 and remained elevated at ∼4.9 mM during sets 4-10; this was despite a decline in work output by Set 4, which fell by 18.9% at set 10. The rise in plasma [K+] x work(-1) ratio was elevated over Set 2 from Set 4- Set 10. Eccentric contractions had no effect on muscle NKA content or maximal in-vitro 3-O-MFPase activity immediately post- or up to 7 d post-exercise. The sustained elevation in plasma [K+] despite a decrease in work performed by the knee extensor muscles suggests an impairment in K+ regulation during maximal eccentric contractions, possibly due to increased plasma membrane permeability or to excitation-contraction uncoupling

From evidence-based research to practice-based evidence : disseminating a web-based computer-tailored workplace sitting intervention through a health promotion organisation

Prolonged sitting has been linked to adverse health outcomes; therefore, we developed and examined a web-based, computer-tailored workplace sitting intervention. As we had previously shown good effectiveness, the next stage was to conduct a dissemination study. This study reports on the dissemination efforts of a health promotion organisation, associated costs, reach achieved, and attributes of the website users. The organisation systematically registered all the time and resources invested to promote the intervention. Website usage statistics (reach) and descriptive statistics (website users' attributes) were also assessed. Online strategies (promotion on their homepage; sending e-mails, newsletters, Twitter, Facebook and LinkedIn posts to professional partners) were the main dissemination methods. The total time investment was 25.6 h, which cost approximately 845 EUR in salaries. After sixteen months, 1599 adults had visited the website and 1500 (93.8%) completed the survey to receive personalized sitting advice. This sample was 38.3 +/- 11.0 years, mainly female (76.9%), college/university educated (89.0%), highly sedentary (88.5% sat >8 h/day) and intending to change (93.0%) their sitting. Given the small time and money investment, these outcomes are positive and indicate the potential for wide-scale dissemination. However, more efforts are needed to reach men, non-college/university educated employees, and those not intending behavioural change

Environmental correlates of physical activity in Australian workplaces

Purpose &ndash; The workplace is an ideal setting to promote physical activity. The purpose of this study is to examine associations with physical activity at and around the workplace.Design/methodology/approach &ndash; Participants were recruited from a random sample of employed adults (n &frac14; 1; 107) in capital cities and major regional centres in Australia. Self-reported barriers and participation in physical activity at and around the workplace were assessed. A multivariable logistic regression model adjusting for age, sex, occupational status, and overall physical activity assessed the odds of being active in this setting.Findings &ndash; Of participants, 61 percent perceived being active in the workplace. Those who perceived their work colleagues and managers to be physically active, and those who indicated that their workplace provides facilities to support them being active had higher odds of being physically active at or around the workplace.Research limitations/implications &ndash; A poor response rate, physically active sample and cross-sectional analysis prevent inferences about the causality of the findings.Originality/value &ndash; The paper provides evidence of the potential for the multiple levels of influence on physical activity at and around the workplace.<br /

Variations in area-level disadvantage of Australian registered fitness trainers usual training locations

BACKGROUND: Leisure-time physical activity and strength training participation levels are low and socioeconomically distributed. Fitness trainers (e.g. gym/group instructors) may have a role in increasing these participation levels. However, it is not known whether the training location and characteristics of Australian fitness trainers vary between areas that differ in socioeconomic status. METHODS: In 2014, a sample of 1,189 Australian trainers completed an online survey with questions about personal and fitness industry-related characteristics (e.g. qualifications, setting, and experience) and postcode of their usual training location. The Australian Bureau of Statistics \u27Index of Relative Socioeconomic Disadvantage\u27 (IRSD) was matched to training location and used to assess where fitness professionals trained and whether their experience, qualification level and delivery methods differed by area-level disadvantage. Linear regression analysis was used to examine the relationship between IRSD score and selected characteristics adjusting for covariates (e.g. sex, age). RESULTS: Overall, 47&nbsp;% of respondents worked in areas within the three least-disadvantaged deciles. In contrast, only 14.8&nbsp;% worked in the three most-disadvantaged deciles. In adjusted regression models, fitness industry qualification was positively associated with a higher IRSD score (i.e. working in the least-disadvantaged areas) (Cert III: ref; Cert IV &beta;:13.44 [95&nbsp;% CI 3.86-23.02]; Diploma &beta;:15.77 [95&nbsp;% CI: 2.17-29.37]; Undergraduate &beta;:23.14 [95&nbsp;% CI: 9.41-36.86]). CONCLUSIONS: Fewer Australian fitness trainers work in areas with high levels of socioeconomic disadvantaged areas than in areas with low levels of disadvantage. A higher level of fitness industry qualifications was associated with working in areas with lower levels of disadvantage. Future research should explore the effectiveness of providing incentives that encourage more fitness trainers and those with higher qualifications to work in more socioeconomically disadvantaged areas

Using the Behavior Change Wheel to Understand University Students’ Prolonged Sitting Time and Identify Potential Intervention Strategies

Background Several national public health guidelines recommend individuals minimize time spent in prolonged, continuous periods of sitting. Developing effective interventions to break up sitting, however, requires in-depth understanding of the behavior as well as identification of the key elements that need to be targeted to achieve change. This qualitative study focused on university students – a highly sedentary group – with the aim of: (i) exploring the factors influencing prolonged sitting time in this population; and (ii) identifying potential avenues for future intervention, based on the Behavior Change Wheel framework. Method Eighteen ambulatory undergraduate students participated in semi-structured one-on-one interviews, using the Capability, Opportunity, Motivation, Behavior (COM-B) model and the complementary Theoretical Domains Framework (TDF) as the theoretical framework. Data were analyzed using a directed content analysis approach, followed by inductive thematic analysis. Results All COM-B components and eight TDF domains were identified as relevant for influencing the target behavior. Conclusion Findings suggest that interventions and policies aimed at reducing prolonged sitting time in university students should: (i) raise awareness about negative health implications; (ii) address productivity concerns; (iii) provide training in behavioral self-regulation; (iv) use external reminders; (v) implement habit formation techniques; and (vi) promote social acceptability for breaking up sitting

Work-related physical activity and psychological distress among women in different occupations : a cross-sectional study

BACKGROUND: Recent evidence suggests that work-related physical activity may not have the same mental health benefits as leisure-time physical activity. Further, work-related physical activity is likely to include a variety of different behaviours for people with different occupations. As such, the aim of this study was to determine if occupation type moderated the association between work-related physical activity and psychological distress. METHODS: A randomly selected sample of 1080 women from Melbourne, Australia completed the International Physical Activity Questionnaire (IPAQ) and General Health Questionnaire (GHQ-30), and reported their current occupation. RESULTS: Linear regression analyses indicated that occupation significantly moderated the association between work-related walking and psychological distress (F [8, 55] = 2.26, p = .036). Given evidence of moderation, we fitted linear regression models to test the associations between work-related physical activity and psychological distress for three separate groups; professionals, sales and services workers, and tradespersons. Female tradespersons who engaged in a low (B = - 3.81, p = .006) or high amount of work-related walking (B = - 3.23, p = .029), had significantly lower psychological distress symptoms than those who engaged in no work-related walking. There were no significant associations between work-related physical activity of any intensity and psychological distress for professionals, or sales and service workers. CONCLUSIONS: Given the relationship does not exist across all occupations, work-related physical activity should not be promoted above and beyond leisure-time physical activity. However, walking at work may be important in reducing psychological distress for some people and should therefore, not be discounted

Risk factors for child stunting in Bangladesh: An analysis using MICS 2019 data

Background Malnutrition is considered a major public health challenge and is associated with a range of health issues, including childhood stunting. Stunting is a reliable and well-recognized indicator of chronic childhood malnutrition. The objective of this study is to determine the risk factors associated with stunting among 17,490 children below five years of age in Bangladesh. Methods Correlates of child stunting were examined using data generated by a cross-sectional cluster survey conducted in Bangladesh in 2019. The data includes a total of 17,490 children (aged \u3c 5 years) from 64,400 households. Multiple logistic regressions were used to determine the risk factors associated with child stunting and severe stunting. Results The prevalence of stunting and severe stunting for children was 25.96% and 7.97%, respectively. Children aged 24 to \u3c 36 months [Odds Ratio (OR) = 2.65, 95% CI: 2.30, 3.05] and aged 36 to \u3c 48 months [OR = 2.33, 95% CI: 2.02, 2.69] had more risk of stunting compared to the children aged \u3c 6 months. Children from Sylhet division had the greatest risk of stunting of all the eight divisions [OR = 1.26, 95% CI: 1.09, 1.46]. Children of secondary complete or higher educated mothers were less likely to develop stunting [OR = 0.66, 95% CI: 0.56, 0.79] compared with children of mothers having no education at all. Similarly, children of secondary complete or higher educated father [OR = 0.74, 95% CI: 0.63, 0.87] were found to have lower risk of stunting compared with children whose father hadn’t any education. Substantially lower risk of stunting was observed among children whose mother and father both completed secondary education or above [OR = 0.59, 95% CI: 0.52, 0.69]. Children from the richest households [OR = 0.49, 95% CI: 0.41, 0.58] had 51% lower odds of stunting compared to children from the poorest households. Conclusions After controlling for socioeconomic and demographic factors, parental education and household position in the wealth index were found to be the most important determinants of child stunting in Bangladesh

Reliability and validity of self-reported sitting and breaks from sitting in the workplace

Objectives Prolonged sitting is a health risk factor which is ubiquitous to the workplace, and breaking up prolonged sitting is widely recommended. This study evaluated the test–retest reliability and concurrent validity of a self-report measure of duration of sitting and breaks from sitting in the workplace. Design Cross-sectional study. Methods Fifty-nine workers who reported spending most of their work time sitting wore an activPAL inclinometer and the ActiGraph accelerometer for eight consecutive days, and completed single-item measures of duration of sitting (min/work hour) and breaks from sitting (frequency/per work hour), twice, seven days apart. Results Participants reported sitting at work for a median of 420 min/day (Interquartile Range = 360–450 min/day) and taking one break (Interquartile Range = 1.0–2.0) from sitting per work hour. For reported duration of workplace sitting, test–retest reliability was adequate (Intra-Class Correlations = 0.78, 95% Confidence Intervals [CI] = 0.65, 0.86), and concurrent validity fair against the activPAL (Spearman’s Rho = 0.24, CI-1.0,0.47) and the ActiGraph (Rho = 0.39, CI = 0.15, 0.68). For reported breaks from sitting (frequency/per work hour), test–retest reliability was adequate (Intra-Class Correlations = 0.65, CI = 0.48, 0.78) and concurrent validity fair against the activPAL (Spearman’s Rho = 0.39, CI = 0.25, 0.74) and the ActiGraph (Spearman’s Rho = 0.30, CI = 0.15, 0.69). Self-reported duration of sitting was biased toward over-reporting compared to the activPAL (median = 45.4 min) and under-reporting compared to the ActiGraph (median = 21.7 min). Conclusions This study found adequate reliability and fair validity for self-reported duration of sitting (min/work day) and breaks from sitting (frequency/per work hour). Further validity research is needed using the inclinometer

Evaluation of the Effectiveness of Disseminating Workplace Health Promotion Resources to Businesses

Encouraging workplaces to undertake health promotion is important yet little is known of the types of information small and medium size workplaces would find useful. Two resources on workplace health promotion were mailed to 213 workplaces. The resources provided information on the benefits of workplace health promotion, suggestions for low-cost activities and components of a sustainable program. 62% of respondents rated the resources as either ‘very useful’ or ‘somewhat useful’. Workplaces in ‘contemplation’ and ‘preparation’ stages of change for engaging in WHP were most likely to have undertaken an activity to support the health and well-being of employees or be intending to, as a result of reading the resources .The findings of this study provide useful information on the reach and impact of dissemination of health promotion resources by mail to workplaces, and particularly small businesses