Overweight, obesity and work functioning: the role of working-time arrangements

Metabolic-Associated Fatty Liver Disease and Insulin Resistance: A Review of Complex Interlinks

Metabolic-associated fatty liver disease (MAFLD) has now surpassed alcohol excess as the most common cause of chronic liver disease globally, affecting one in four people. Given its prevalence, MAFLD is an important cause of cirrhosis, even though only a small proportion of patients with MAFLD ultimately progress to cirrhosis. MAFLD suffers as a clinical entity due to its insidious and often asymptomatic onset, lack of an accurate and reliable non-invasive diagnostic test, and lack of a bespoke therapy that has been designed and approved for use specifically in MAFLD. MAFLD sits at a crossroads between the gut and the periphery. The development of MAFLD (including activation of the inflammatory cascade) is influenced by gut-related factors that include the gut microbiota and intactness of the gut mucosal wall. The gut microbiota may interact directly with the liver parenchyma (through translocation via the portal vein), or indirectly through the release of metabolic metabolites that include secondary bile acids, trimethylamine, and short-chain fatty acids (such as propionate and acetate). In turn, the liver mediates the metabolic status of peripheral tissues (including insulin sensitivity) through a complex interplay of hepatokines, liver-secreted metabolites, and liver-derived micro RNAs. As such, the liver plays a key central role in influencing overall metabolic status. In this concise review, we provide an overview of the complex mechanisms whereby MAFLD influences the development of insulin resistance within the periphery, and gut-related factors impact on the development of MAFLD. We also discuss lifestyle strategies for optimising metabolic liver health.

Implications of Resveratrol in Obesity and Insulin Resistance: A State-of-the-Art Review

Background: Resveratrol is a polyphenol chemical that naturally occurs in many plant-based dietary products, most notably, red wine. Discovered in 1939, widespread interest in the potential health benefits of resveratrol emerged in the 1970s in response to epidemiological data on the cardioprotective effects of wine. Objective: To explore the background of resveratrol (including its origins, stability, and metabolism), the metabolic effects of resveratrol and its mechanisms of action, and a potential future role of dietary resveratrol in the lifestyle management of obesity. Data sources: We performed a narrative review, based on relevant articles written in English from a Pubmed search, using the following search terms: “resveratrol”, “obesity”, “Diabetes Mellitus”, and “insulin sensitivity”. Results: Following its ingestion, resveratrol undergoes extensive metabolism. This includes conjugation (with sulfate and glucuronate) within enterocytes, hydrolyzation and reduction within the gut through the action of the microbiota (with the formation of metabolites such as dihydroresveratrol), and enterohepatic circulation via the bile. Ex vivo studies on adipose tissue reveal that resveratrol inhibits adipogenesis and prevents the accumulation of triglycerides through effects on the expression of Peroxisome Proliferator-activated Receptor γ (PPARγ) and sirtuin 1, respectively. Furthermore, resveratrol induces anti-inflammatory effects, supported by data from animal-based studies. Limited data from human-based studies reveal that resveratrol improves insulin sensitivity and fasting glucose levels in patients with Type 2 Diabetes Mellitus and may improve inflammatory status in human obesity. Although numerous mechanisms may underlie the metabolic benefits of resveratrol, evidence supports a role in its interaction with the gut microbiota and modulation of protein targets, including sirtuins and proteins related to nitric oxide, insulin, and nuclear hormone receptors (such as PPARγ). Conclusions: Despite much interest, there remain important unanswered questions regarding its optimal dosage (and how this may differ between and within individuals), and possible benefits within the general population, including the potential for weight-loss and improved metabolic function. Future studies should properly address these important questions before we can advocate the widespread adoption of dietary resveratrol supplementation.

Obesity and individual performance: the case of eSports

BACKGROUND/OBJECTIVES

The study considers the problem of the inclusion of people with obesity in the context of the growing role of computer-based work. Negative stereotypes about people with obesity still hold even when they are irrelevant in tasks that require little physical activity.

SUBJECTS/METHODS

Using data from the realm of competitive video gaming (eSports) and image recognition-based metric of body mass index metric derived from artificial intelligence, we examine the individual performance depending on weight. The sample includes 821 players and 127,533 player performance observations.

RESULTS

For shorter tasks, individuals with normal weight performed better than individuals with obesity. For longer tasks, however, people with Class III (severe) obesity outperformed all others, and their advantage increased with task duration.

CONCLUSIONS

Our findings shed light on an understanding of how actually body features are related to objective individual performance in a competitive context.

Modification Effect of Job Demand and Contingent Work Schedule on Overweight and Obesity Among Civil Servants in Taiwan

OBJECTIVE

Evidence indicated that shift work is a contributing factor to risk of obesity and leads to cardiovascular diseases (CVDs), but few researches have examined the moderating effects of job demand and contingent work schedule on overweight and obesity. Thus, we assessed the modification effect of contingent work schedules and job demand on overweight and obesity among Taiwan's civil servants.

METHODS

Multistage stratified random cluster sampling was used based on a proportional probabilistic sampling (PPS) in a national survey for civil servants. A total of 20,046 participants from 647 registered governmental institutions were enrolled and anonymously and voluntarily filled out web-based questionnaires.

RESULTS

Compared to fixed work schedule, odd ratios (ORs) of obesity and overweight were 1.63 and 1.78 times in contingent work schedule, respectively. In addition, the modification effects of contingent work schedule and high job demand on overweight and obesity with Rothman's synergy index were 2.43 and 2.56, respectively. Using a hierarchical regression model adjusted for covariates, both high job demand and contingent work schedule were interactively associated with overweight and obesity compared to low job demand and fixed work schedule.

CONCLUSION

Since precarious schedules affect employee's obesity through work-related stress and unhealthy behaviors, further research is needed to determine whether interventions aimed at modification of work schedule may be useful in combating obesity.

Obesity impacts on task performance and perceived discomfort during seated foot target reaches

This study examined obesity impacts on task performance and perceived discomfort during seated foot target reaches. Three independent variables, participant group, movement distance, and, movement direction, were considered. The task performance measures employed were reaction time, movement time and task performance time. Perceived discomfort was measured using a modified Borg CR-10 scale. Statistical analyses revealed that: obesity was associated with increases in movement time, reaction time and performance time; movement distance significantly affected the three task performance measures and discomfort rating; and, movement direction significantly affected movement time, performance time and discomfort rating. The obesity impacts observed are thought to reflect the decelerating effects of the extra fat mass in the obese body during foot reaches and possibly obesity-related physiological and cognitive changes. Design improvements of foot-operated systems, such as reducing distances to targets, increasing target sizes and avoiding forward foot reaches, may help counteract the observed obesity impacts. Practitioner Summary: This study empirically investigated the obesity impacts on task performance and perceived discomfort during seated foot target reaches. Obesity was found to be associated with increases in movement time, reaction time and performance time. The observed obesity impacts seem attributable to the anthropometric, motor and cognitive characteristics of the obese.Abbreviations: ANOVA: analysis of variance; BMI: body mass index; ROM: range of motion; Borg CR-10: Borg's category ratio 10 scale.

Low interest in physical activity and higher rates of obesity among rural teachers

BACKGROUND

Few studies have evaluated the causes of physical inactivity in rural teachers from South America. Determining the causes and effects of physical inactivity in rural teachers could be the base for future intervention studies aiming to improve physical activity (PA) engagement in this population.

OBJECTIVES

To examine the levels of PA in rural teachers and evaluate the associations between their jobs, interest in PA, body composition and practice of PA.

METHODS

Body mass index (BMI) and body fat % (BF) of rural teachers from the Valparaiso Region in Chile were measured; interviews regarding PA habits, interests and PA practice were conducted. The relationship between BF% and interest in PA and the practice of sports was analysed stratifying by sex.

RESULTS

Around 71% were overweight/obese and 80% of the teachers reported not practicing any PA. These figures are higher than the Chilean national average for adults (64.5% overweight/obese). Moreover, females presented a higher BF% than male teachers (35.98% vs. 26.44%, p < 0.05). The main causes of not performing PA were: firstly, the lack of time (51.8%), and secondly, fatigue after work and/or finishing work late. In addition, rural teachers claim that in their free time they continue to finish tasks that they were not able to complete during their working hours.

CONCLUSIONS

Rural Chilean teachers show a high prevalence of obesity and low PA levels. Moreover, rural teachers have a work overload stemming from their jobs, and this could be an important link to an overall sedentary lifestyle. Further studies should focus on the relationship between teacher obesity, physical activity, nutrition and work overload.

The Health Benefits of Dietary Fibre

Background: Dietary fibre consists of non-digestible forms of carbohydrate, usually as polysaccharides that originate from plant-based foods. Over recent decades, our diet within Westernised societies has changed radically from that of our hominid ancestors, with implications for our co-evolved gut microbiota. This includes increased ingestion of ultra-processed foods that are typically impoverished of dietary fibre, and associated reduction in the intake of fibre-replete plant-based foods. Over recent decades, there has been a transformation in our understanding of the health benefits of dietary fibre. Objective: To explore the current medical literature on the health benefits of dietary fibre, with a focus on overall metabolic health. Data Sources: We performed a narrative review, based on relevant articles written in English from a PubMed search, using the terms ‘dietary fibre and metabolic health’. Results: In the Western world, our diets are impoverished of fibre. Dietary fibre intake associates with overall metabolic health (through key pathways that include insulin sensitivity) and a variety of other pathologies that include cardiovascular disease, colonic health, gut motility and risk for colorectal carcinoma. Dietary fibre intake also correlates with mortality. The gut microflora functions as an important mediator of the beneficial effects of dietary fibre, including the regulation of appetite, metabolic processes and chronic inflammatory pathways. Conclusions: Multiple factors contribute to our fibre-impoverished modern diet. Given the plethora of scientific evidence that corroborate the multiple and varied health benefits of dietary fibre, and the risks associated with a diet that lacks fibre, the optimization of fibre within our diets represents an important public health strategy to improve both metabolic and overall health. If implemented successfully, this strategy would likely result in substantial future health benefits for the population.

Analyzing the effect of social interaction on job demands and health in the example of flexible shiftwork

In the literature, shiftwork-related stress is often connected with health complaints. However, it has been shown that these are not equally distributed. Further reasons must exist as to why stress resulting from shiftwork only affects health in some cases. In a study with 653 employees working in highly flexible shiftwork conditions, an examination was made of the factors affecting the relationship between job demands and health status. The results show that satisfaction with leadership influences whether unevenly distributed work and time pressure have a significant impact on health. The factor of other people living in the household significantly influences whether time pressure and emotional stress lead to health complaints. The study concluded that the impact of social interaction as a resource is not limited to the workplace. Social interaction, as a personal resource, can be helpful in both the professional and private spheres.

The Impact of Heat on Health and Productivity among Maize Farmers in a Tropical Climate Area

Background

Heat stress disorders may cause negative health outcome and subsequent productivity reduction especially in those who work under direct sunlight for an extended number of hours.

Objective

This study assessed the impact of heat on the health and productivity among maize farmers in a hot tropical country.

Methods

A cross-sectional study was conducted among 396 maize farmers, randomly selected across Gombe province, Nigeria. The wet bulb globe temperature monitor (WBGT) Model QuesTemp⁰36 was used in determining the heat index. Health was determined using a validated questionnaire, while productivity was determined by recording work output based on the number of ridges cultivated during the working hours.

Results

The farms recorded mean heat index with standard deviation (SD) of 31.56 (2.19) and 34.08 (1.54) in the hours of 9 am to 12 pm and 12–3 pm respectively, which exceeded the threshold level set by the ACGIH. Heavy sweating (93.2%), tiredness (48.5%), dizziness (34.1%), and headache (40.4%) were experienced by the respondents almost on daily basis. The finding further showed a significant difference in the farmers' productivity during the three time duration of the work day (p < 0.001). The productivity was significantly higher between the hours of 6–9 am (p < 0.001) and 12–3 pm (p < 0.001), compared to the hours of 9 am to 12 pm (p < 0.001). The factors that significantly predict the productivity outcome include temperature (p < 0.001), gender (p < 0.001), age (p=0.033), and BMI (p=0.008).

Conclusion

The farmers were frequently experiencing heat exhaustion which decreased their productivity.

Obesity effects on muscular activity during lifting and lowering tasks

Obesity is an emerging health problem and its incidence has been increasing throughout the workforce. In industrial workstations, vertical handling tasks (VHT), including lifting and lowering, are very common and can cause a significant muscular overload for the involved workers. During these tasks, muscular activity may be considerably affected by workers' body conditions. This study aims to analyze and compare the muscular activity in subjects with different obesity levels, using surface electromyography (EMG), during predefined VHT. Six different VHT (combining 5, 10 and 15-kg loads with two task styles) were performed. EMG data normalization was based on the percentage of maximum contraction during each task (MCT%). The results show that obesity influences the MCT%, which in turn increases the muscular effort during VHT. The current investigation demonstrates that obesity is a relevant musculoskeletal risk factor regarding VHT. The engineering analysis and design implications of this work can thus be perceived.

Determinants of sleepiness at work among railway control workers

In the last two decades the control of the Portuguese railway network has become much more centralized in three centres, there integrating the functions of route flow management, electrical control and signalling. This study aimed to investigate the influence of work and individual determinants in sleepiness among railway control workers, namely socio-demographic factors, work ability, psychosocial factors, shiftwork characteristics, fatigue perception, and sleep. Sleepiness by shift was associated with quality of sleep, job satisfaction, fatigue perception, quantitative demands, and age. The results indicate a high prevalence of sleepiness during the night shift and show the relevance of the quality of sleep as a predictor in the three models of sleepiness for morning, afternoon and night shifts. This study, done at the major Portuguese railway control centre, alerted managers to the importance of schedule planning as well as sleepiness prevention plans and makes these results a reference for future research.