Evaluation of measurement properties of the German Work Role Functioning Questionnaire.

OBJECTIVE: We assessed the measurement properties of the German Work Role Functioning Questionnaire (WRFQ) after its cross-cultural adaptation of the Dutch version. The WRFQ is a generic role-specific instrument that measures how a particular health status influences the ability to meet work demands. METHODS: We performed an observational study among German employees assessing the following measurement properties: 1) structural, 2) convergent and 3) discriminant validity, 4) floor and ceiling effects, 5) internal consistency, 6) reproducibility and 7) responsiveness. Participants were recruited from an online access panel sample aged 18 to 64 years having worked more than 12 hours in the last 4 weeks prior to study enrollment (n(T0) = 653, n(T1) = 66, n(T2) = 95). RESULTS: Measurement properties proved to be good except for structural validity and responsiveness. An exploratory factor analysis showed limited replicability of three of the four original subscales. CONCLUSION: With the WRFQ German version, the extent can be measured, to which employees with a certain health level experience problems can meet their work demands. This widely used health-related work outcome measurement tool, that helps to identify employees with decreasing work functioning, is now also available in German. This gives researchers and practitioners the opportunity to address work functioning in practice, e.g. in intervention studies in occupational health or rehabilitation. Further research to examine valid subscales is needed.

Opioid overprescription in adolescents and young adults undergoing hip arthroscopy.

Few studies have examined factors related to the increased consumption of opioids after hip arthroscopy in adolescents and young adults. This study sought to determine prescription patterns following hip arthroscopy in this population, and to determine clinical or surgical factors associated with increased post-operative opioid use. Daily post-operative opioid intake was obtained from pain-control logbooks of adolescents and young adults who underwent hip arthroscopy between January 2017 and 2020. Study outcomes were defined as the median total number of opioid tablets consumed, total days opioids were consumed, mean daily opioid consumption and the ratio of opioids prescribed post-operatively to consumed. Clinical and surgical factors were analyzed to determine any association with opioid consumption. Fifty-eight (20%) patients returned completed logbooks. Most patients (73%) were prescribed 30 oxycodone tablets. The median number of tablets consumed was 7 (range 0-41) over a median duration of 7 days (range 1-22). The median ratio of tablets consumed to prescribed was 20%. Increasing patient age at surgery was associated with increased total number of tablets consumed (r = 0.28, P = 0.04) and to the ratio of tablets consumed to prescribed (r = 0.30, P = 0.03). Patients who were prescribed more than 30 tablets consumed on average 7.8 more tablets than patients prescribed fewer (P = 0.003). Patients who underwent regional anesthesia consumed tablets for longer compared with those who did not (median, 10 versus 4 days; P = 0.03). After undergoing hip arthroscopy, adolescents and young adult patients are commonly overprescribed opioids, consuming on average only one-fifth of the tablets prescribed.

The effect of sampling density and study area size on landscape genetics inferences for the Mississippi slimy salamander (Plethodon mississippi).

In landscape genetics, it is largely unknown how choices regarding sampling density and study area size impact inferences upon which habitat features impede vs. facilitate gene flow. While it is recommended that sampling locations be spaced no further apart than the average individual's dispersal distance, for low-mobility species, this could lead to a challenging number of sampling locations, or an unrepresentative study area. We assessed the effects of sampling density and study area size on landscape genetic inferences for a dispersal-limited amphibian, Plethodon mississippi, via analysis of nested datasets. Microsatellite-based genetic distances among individuals were divided into three datasets representing sparse sampling across a large study area, dense sampling across a small study area, or sparse sampling across the same small study area. These datasets were a proxy for gene flow (i.e., the response variable) in maximum-likelihood population effects models that assessed the nature and strength of their relationship with each of five land-use classes (i.e., potential predictor variables). Comparisons of outcomes were based on the rank order of effect, sign of effect (i.e., gene flow resistance vs. facilitation), spatial scale of effect, and functional relationship with gene flow. The best-fit model for each dataset had the same sign of effect for hardwood forests, manmade structures, and pine forests, indicating the impacts of these land-use classes on dispersal and gene flow in P. mississippi are robust to sampling scheme. Contrasting sampling densities led to a different inferred functional relationship between agricultural areas and gene flow. Study area size appeared to influence the scale of effect of manmade structures and the sign of effect of pine forests. Our findings provided evidence for an influence of sampling density, study area size, and sampling effort upon inferences. Accordingly, we recommend iterative subsampling of empirical datasets and continued investigation into the sensitivities of landscape genetic analyses using simulations.

Mental Health Applications for Primary and Secondary Prevention of Common Mental Disorders: Attitudes of German Employees.

Background: Web-based and mobile mental health applications for the prevention and treatment of common mental disorders (CMDs) are on the rise. Under certain circumstances they have proved to be effective for a range of conditions (e.g., depression). Objective: There is not sufficient evidence regarding the benefits and barriers especially for mobile phone apps and for programs in the field of primary prevention. Studies on the acceptance of potential users of mental health apps yielded mixed outcomes. In a large survey we investigated the attitudes of employees toward mental health apps and various traditional mental health services. Our main research question in this contribution focuses on the acceptance of apps compared to other measures and the moderating influence of individual characteristics. Methods: The standardized survey was completed by members of an online access panel with different job types. A set of 33 self-developed items, including three questions on e-health, captured the perceived relevance of prevention at the (A) occupational, (B) individual, and (C) societal level. On the basis of an exploratory factor analysis, mean scores for mapping seven (sub-)dimensions were constructed and compared using the Wilcoxon test. The influence of potential predictors was analyzed in linear regression models. Results: The data of 610 respondents were analyzed (response rate 75%). Support from mental health applications was rated significantly less important compared to all other dimensions at the levels (A) to (C). Respondents were more likely to use mental health apps if they felt literate with electronic devices, perceived a high relevance of work-related demands as causal factors for CMDs, stated they would be ashamed of having a CMD, and would be willing to begin psychotherapy if recommended. Discussion and Conclusions: The results confirm the critical attitudes of potential mental health app users found in other studies. Since users with a negative attitude toward e-health might have a higher risk for dropout and non-adherence as well as lower intervention effects, well-designed educational strategies should be carried out beforehand.

Work-Related Psychosocial Stress in Small and Medium-Sized Enterprises: An Integrative Review.

Background: Work-related psychosocial stress can cause mental and physical illnesses resulting in high costs for the individual, the economy and society. Small and medium-sized enterprises (SMEs) employ the majority of the world's workforce and often have fewer financial and human resources compared to larger businesses. The aim of this review is to summarize current knowledge on work-related stress in SMEs according to well-established guidelines categorizing psychosocial factors at work. Methods: A systematic database search was carried out in PubMed, PsycINFO, PSYNDEX and Business Source Premiere from March to June 2019, updated in January 2020. Data of included studies were analyzed and mapped into five themes: "work content and task", "organization of work", "social relations", "working environment" and "new forms of work". Results: After full-text screening, 45 out of 116 studies were included for data extraction. Studies were very heterogeneous and of varying quality, mostly applying a cross-sectional study design. Psychosocial factors in SMEs have been researched with a focus on the work patterns "work organization" and "work content and task". Conclusions: This review underlines the need for more and better quality research of psychosocial factors in SMEs, particularly in relation to ongoing and new challenges in the workplace, including stressors related to the process of digitalization or the development of safe working conditions during the emerge of new infectious diseases.

Return-To-Play Decision Making in Team Sports Athletes. A Quasi-Naturalistic Scenario Study.

Competitive athletes act within cultures of risk in sports and often decide to return to sport despite having acute health problems. The outcomes of such risky return-to-play decisions can not only negatively affect their future health, but may also limit their sports performance or even upset their career paths. Following risk-management-decision theory with its focus on active risk defusing, we developed a model for understanding the process of return-to-play decision making from an athlete's perspective. Based on the method of active information search, a quasi-naturalistic return-to-play decision scenario was created in order to assess amateur team sport athletes' decision-making strategies. The main goals were to identify different information acquisition patterns and to analyze the influence of varying sporting consequences on decision making. A total of 72 competitive team sport athletes (36 females, 36 males, m = 25.7 years of age, 3rd to 6th league level) from three disciplines (volleyball, basketball, and handball) participated in the experimental study. Facing the same medical scenario (a partial tear of the supraspinatus tendon), athletes show different approaches to return-to-play decision making. The main focus is on the potential sporting consequences of withdrawal from competition due to injury, with only a few players favoring well-informed decisions based on thorough risk analysis. The athletes who chose the medically risky alternative to play hurt mostly employed strategies of active risk defusing, which got activated when severe sporting consequences were perceived. Those who chose to withdraw from competition primarily referred to maximin heuristic, particularly when social pressure to play was reduced. The findings can be used to improve rehabilitation-related communication and shared return-to-play decision making in sports.

The Effect of Exercise Training on Total Daily Energy Expenditure and Body Composition in Weight-Stable Adults: A Randomized, Controlled Trial.

BACKGROUND: The present study examined, among weight-stable overweight or obese adults, the effect of increasing doses of exercise energy expenditure (EEex) on changes in total daily energy expenditure (TDEE), total body energy stores, and body composition. METHODS: Healthy, sedentary overweight/obese young adults were randomized to one of 3 groups for a period of 26 weeks: moderate-exercise (EEex goal of 17.5 kcal/kg/wk), high-exercise (EEex goal of 35 kcal/kg/wk), or observation group. Individuals maintained body weight within 3% of baseline. Pre/postphysical activity between-group measurements included body composition, calculated energy intake, TDEE, energy stores, and resting metabolic rate. RESULTS: Sixty weight-stable individuals completed the protocols. Exercise groups increased EEex in a stepwise manner compared with the observation group (P < .001). There was no group effect on changes in TDEE, energy intake, fat-free mass, or resting metabolic rate. Fat mass and energy stores decreased among the females in the high-exercise group (P = .007). CONCLUSIONS: The increase in EEex did not result in an equivalent increase in TDEE. There was a sex difference in the relationship among energy balance components. These results suggest a weight-independent compensatory response to exercise training with potentially a sex-specific adjustment in body composition.

Common mental disorders through the eyes of German employees: attributed relevance of work-related causes and prevention measures assessed by a standardised survey.

PURPOSE: Common mental disorders (CMDs) are becoming increasingly relevant in the working world. Numbers of risk factors have been confirmed by mostly correlative cross-sectional studies. Comprehensive and effective prevention is urgently needed. There is little knowledge about employees' own perceptions on causes of CMDs and prevention measures. Therefore, a survey was conducted in 2016. METHODS: A standardised instrument was developed for an online survey in a commercial access panel, targeted employees in different job types. We assessed two outcomes: perceived relevance of (1) work-related demands to the development of CMDs, and (2) prevention approaches in the workplace and on individual and societal levels. Possible predictive aspects were analysed exploratively by multivariate linear regression analysis. RESULTS: The response rate was 75% (n = 610). Job types were categorised as "blue", "grey" and "white-collar" workers (n = 193, 169, 248). The majority of respondents rated both outcomes consistently as "quite" or "very relevant"; societal prevention strategies were more relevant for non-white-collar workers. Perceived relevance of individual predisposition to develop a CMD was the strongest predictor for both outcomes, indicating the perception that people with higher personal vulnerability might suffer a higher strain from work-related risk factors than others. CONCLUSION: We assume that participants in our survey judged the relevance of work-related causes of CMDs independently of their own workload. The perceived relevance of prevention measures in different areas is consistent with official guidelines. A possible selection bias due to characteristics of access panel collectives and own direct or indirect experiences with CMD should be critically questioned.

Relationships between chronotype, social jetlag, sleep, obesity and blood pressure in healthy young adults.

Sleep disturbances, chronotype and social jetlag (SJL) have been associated with increased risks for major chronic diseases that take decades to develop, such as obesity, metabolic syndrome and cardiovascular disease. Potential relationships between poor sleep, chronotype and SJL as they relate to metabolic risk factors for chronic disease have not been extensively investigated. This prospective study examined chronotype, SJL and poor sleep in relation to both obesity and elevated blood pressure among healthy young adults. SJL and objective sleep measures (total sleep time, sleep onset latency, wake after sleep onset and sleep efficiency) were derived from personal rest/activity monitoring (armband actigraphy) among 390 healthy adults 21-35 years old. Participants wore the device for 6-10 days at 6-month intervals over a 2-year period (n = 1431 repeated observations). Chronotypes were categorized into morning, intermediate and evening groups using repeated measures latent class analysis. Means of SJL and sleep measures among latent chronotype groups were compared using partial F-tests in generalized linear mixed models. Generalized linear mixed models also were used to generate odds ratios (ORs) with 95% confidence intervals (CIs) examining the relationship between repeated measures of chronotype, SJL, sleep and concurrent anthropometric outcome measures (body mass index, percentage of body fat, waist-to-hip ratio, waist-to-height ratio), systolic blood pressure and diastolic blood pressure. Sleep latency ≥12 min was associated with increased odds of a high waist-to-height ratio (OR = 1.37; CI: 1.03-1.84). Neither chronotype nor SJL was independently associated with anthropometric outcomes or with blood pressure. Relationships between poor sleep and anthropometric outcomes or blood pressure varied by chronotype. Morning types with total sleep time <6 h, sleep efficiency <85% or wake after sleep onset ≥60 min were more likely to have an increased percentage of body fat, waist-to-hip ratio and waist-to-height ratio relative to those with an intermediate chronotype. Similarly, sleep latency ≥12 min was associated with increased odds of elevated systolic blood pressure (OR = 1.90; CI: 1.15-3.16, pinteraction = 0.02) among morning versus intermediate chronotypes. No relationships between poor sleep and obesity or elevated blood pressure were observed among evening chronotypes. The results from this study among healthy young adults suggest that poor sleep among morning types may be more strongly associated with obesity and elevated blood pressure relative to those with an intermediate (neutral) chronotype. Sleep-related metabolic alterations among different chronotypes warrant further investigation.

Opioid Overprescription After Knee Arthroscopy and Related Surgery in Adolescents and Young Adults.

PURPOSE: The purpose of this study was to compare the number of opioids prescribed with the amount of pain medication required after knee arthroscopy and related surgery in adolescent and young adult patients to determine the effectiveness of current pain-control practices at a single institution. The secondary purpose was to determine what demographic or surgical factors are associated with increased opioid intake. METHODS: Adolescent and young adult patients who underwent knee arthroscopy and related surgery, including ligament reconstruction or tibial tubercle osteotomy, between May and August 2016 were provided pain-control logbooks in which they were asked to maintain a record of daily pain medication intake. The outcome of the study was defined as the total number of opioids consumed per patient. RESULTS: One hundred patients returned completed logbooks, 56% of whom were female patients. The average age was 17.54 years (standard deviation [SD], 3.51 years). Most patients underwent an open procedure concurrent with knee arthroscopy (60%), underwent nerve block placement (51%), and underwent injection of local anesthesia (91%). Use of both intravenous acetaminophen and ketorolac during the perioperative period was also common (41%). Patients were prescribed an average of 50.98 oxycodone pills (SD, 12.50 pills) and reported consuming an average of 16.52 pills (SD, 13.94 pills), approximately 32.4% of those prescribed. Eleven percent never consumed opioids, and only 1 patient requested a refill during the 21-day postoperative period. Multivariate analysis showed that increased weight, longer surgery time, and increased diazepam use were most closely associated with increased opioid consumption. CONCLUSIONS: After knee arthroscopy and related surgery, including ligament reconstruction or tibial tubercle osteotomy, adolescent and young adult patients are commonly overprescribed opioids, consuming on average only approximately one-third of those prescribed. LEVEL OF EVIDENCE: Level IV, case series.

Changes in sedentary time are associated with changes in mental wellbeing over 1 year in young adults.

Excessive sedentary time is related to poor mental health. However, much of the current literature uses cross-sectional data and/or self-reported sedentary time, and does not assess factors such as sedentary bout length. To address these limitations, the influence of objectively measured sedentary time including sedentary bout length (i.e. <30 min, ≥30 min) on mood, stress, and sleep, was assessed in 271 healthy adults (49% women; age 27.8 ±â€¯3.7) across a 1-year period between 2011 and 2013 in Columbia, SC. Participants completed the Profile of Mood States and the Perceived Stress Scale, and wore a Sensewear Armband to assess sedentary time, physical activity, and sleep for ten days at baseline and one year. A series of fixed-effects regressions was used to determine the influence of both baseline levels and changes in daily sedentary time (total and in bouts) and physical activity on changes in mood, stress, and sleep over one year. Results showed that across the year, decreases in total sedentary time, and time in both short and long bouts, were associated with improvements in mood, stress and sleep (p < 0.05). Increases in physical activity were only significantly predictive of increases in sleep duration (p < 0.05). Thus, reductions in sedentary time, regardless of bout length, positively influenced mental wellbeing. Specifically, these results suggest that decreasing daily sedentary time by 60 min may significantly attenuate the negative effects of high levels of pre-existing sedentary time on mental wellbeing. Interventions manipulating sedentary behavior are needed to determine a causal link with wellbeing and further inform recommendations.

The Influence of Life Events and Psychological Stress on Objectively Measured Physical Activity: A 12-Month Longitudinal Study.

BACKGROUND: This study examined how life event occurrences and stressfulness influence objectively measured light through vigorous physical activity (PA) among young adults. METHODS: Every 3 months over a 12-month period, 404 healthy young adults completed questionnaires on the occurrence and stress of 16 life events and wore an accelerometer for 10 days. RESULTS: A modest positive relationship was seen between cumulative life event occurrences [between effect: ß = 22.2 (9.7) min/d, P = .02] and cumulative stress [between effect: ß = 7.6 (2.9) min/d, P = .01] with light through vigorous PA among men. When considering events individually, job change, starting a first job, beginning a mortgage, and changes in a relationship influenced men's PA. For women, mortgage, starting a first job, job change, and engagement had significant associations. Life event stressfulness influenced PA in women more than in men. For men, stress from changes in a relationship or job positively influenced PA. Stress of a mortgage, quitting a job, changing jobs or a first job influenced women's PA. CONCLUSION: Considering each life event individually was more informative than the summation of life events or summation of stress. Specific life events substantially altered PA, and this change varied by gender, direction of association, and PA intensity and duration.

Persistence of social jetlag and sleep disruption in healthy young adults.

Sleep disruption has been associated with increased risks for several major chronic diseases that develop over decades. Differences in sleep/wake timing between work and free days can result in the development of social jetlag (SJL), a chronic misalignment between a person's preferred sleep/wake schedule and sleep/wake timing imposed by his/her work schedule. Only a few studies have examined the persistence of SJL or sleep disruption over time. This prospective investigation examined SJL and sleep characteristics over a 2-year period to evaluate whether SJL or poor sleep were chronic conditions during the study period. SJL and sleep measures (total sleep time [TST], sleep onset latency [SOL], wake after sleep onset [WASO]), and sleep efficiency [SE]), were derived from armband monitoring among 390 healthy men and women 21-35 years old. Participants wore the armband for periods of 4-10 days at 6-month intervals during the follow-up period (N = 1431 repeated observations). The consistency of SJL or sleep disruption over time was analyzed using generalized linear mixed models (GLMMs) for repeated measures. Repeated measures latent class analysis (RMLCA) was then used to identify subgroups among the study participants with different sleep trajectories over time. Individuals in each latent group were compared using GLMMs to identify personal characteristics that differed among the latent groups. Minor changes in mean SJL, chronotype, or TST were observed over time, whereas no statistically significant changes in SOL, WASO, or SE were observed during the study period. The RMLCA identified two groups of SJL that remained consistent throughout the study (low SJL, mean ± SE: 0.4 ± 0.04 h, 42% of the study population; and high SJL, 1.4 ± 0.03 h, 58%). Those in the SJL group with higher values tended to be employed and have an evening chronotype. Similarly, two distinct subgroups were observed for SOL, WASO, and SE; one group with a pattern suggesting disrupted sleep over time, and another with a consistently normal sleep pattern. Analyses of TST identified three latent groups with relatively short (5.6 ± 1.0 h, 21%), intermediate (6.5 ± 1.0 h, 44%), and long (7.3 ± 1.0 h, 36%) sleep durations, all with temporally stable, linear trajectories. The results from this study suggest that sleep disturbances among young adults can persist over a 2 year period. Latent groups with poor sleep tended to be male, African American, lower income, and have an evening chronotype relative to those with more normal sleep characteristics. Characterizing the persistence of sleep disruption over time and its contributing factors could be important for understanding the role of poor sleep as a chronic disease risk factor.

Cross-sectional and longitudinal associations between different exercise types and food cravings in free-living healthy young adults.

INTRODUCTION: An increase in energy intake due to alterations in hedonic appetite sensations may, at least in part, contribute to lower-than-expected weight loss in exercise interventions. The aim of this study was to examine cross-sectional and longitudinal associations between habitual exercise participation and food cravings in free-living young adults. METHODS: A total of 417 adults (49% male, 28 ± 4 years) reported frequency and duration of walking, aerobic exercise, resistance exercise and other exercise at baseline and every 3 months over a 12-month period. Food cravings were assessed via the Control of Eating Questionnaire at baseline and 12-month follow-up. RESULTS: Cross-sectional analyses revealed more frequent cravings for chocolate and a greater difficulty to resist food cravings in women compared to men (p < 0.01). Only with resistance exercise significant sex by exercise interaction effects were observed with favorable responses in men but not in women. Significant main effects were shown for walking and aerobic exercise with exercisers reporting more frequent food cravings for chocolate and fruits and greater difficulty to resist eating compared to non-exercisers (p < 0.05). Longitudinal analyses revealed significant interaction effects for other exercise (p < 0.05) with favorable results in men but not women. Furthermore, significant main effects were observed for aerobic exercise, resistance exercise and total exercise with an increase in exercise being associated with a reduced difficulty to resist food cravings (p < 0.05). DISCUSSION: The association between exercise participation and hedonic appetite sensations varies by exercise type and sex. Even though exercise was associated with more frequent and greater difficulty to food cravings in the cross-sectional analyses, which may be attributed to greater energy demands, longitudinal results indicate beneficial effects of increased exercise on appetite control, particularly in men.

The Association of Physical Activity during Weekdays and Weekend with Body Composition in Young Adults.

Physical activity (PA) is a key contributor in long-term weight management but there remains limited research on the association between weekly PA patterns and weight change. The purpose of the present study was to examine the prospective association between weekly PA patterns and weight change in generally healthy young adults. Anthropometric measurements, including dual X-ray absorptiometry, were obtained every 3 months over a period of one year in 338 adults (53% male). At each measurement time, participants wore a multisensor device for a minimum of 10 days to determine total daily energy expenditure and time spent sleeping, sedentary, in light PA (LPA), in moderate PA (MPA), and in vigorous PA (VPA). PA did not differ between weekdays and the weekend at baseline. Twenty-four-hour sleep time, however, was significantly longer during weekends compared to weekdays, which was associated with less time spent sedentary. Weight loss was associated with a significant increase in LPA at the expense of sedentary time during the weekend but not during weekdays. Regression analyses further revealed an inverse association between change in VPA during the weekend and body composition at 12-month follow-up. Taken together, these results suggest that weekend PA plays an important role in long-term weight management.

Subjective Estimation of Physical Activity Using the International Physical Activity Questionnaire Varies by Fitness Level.

BACKGROUND: Subjective measures of moderate and vigorous physical activity (MVPA) rely on relative intensity whereas objective measures capture absolute intensity; thus, fit individuals and unfit individuals may perceive the same activity differently. METHODS: Adults (N = 211) wore the SenseWear Armband (SWA) for 10 consecutive days to objectively assess sedentary time and MVPA. On day 8, participants completed the International Physical Activity Questionnaire (IPAQ) to subjectively assess sitting time and MVPA. Fitness was assessed via a maximal treadmill test, and participants were classified as unfit if the result was in the bottom tertile of the study population by sex or fit if in the upper 2 tertiles. RESULTS: Overall, estimates of MVPA between the IPAQ and SWA were not significantly different (IPAQ minus SWA, 67.4 ± 919.1 MVPA min/wk, P = .29). However, unfit participants overestimated MVPA using the IPAQ by 37.3% (P = .02), but fit participants did not (P = .99). This between-group difference was due to overestimation, using the IPAQ, of moderate activity by 93.8 min/wk among the unfit individuals, but underestimation of moderate activity among the fit participants by 149.4 min/wk. CONCLUSION: Subjective measures of MVPA using the IPAQ varied by fitness category; unfit participants overestimated their MVPA and fit participants accurately estimated their MVPA.

Hepatitis B virus seroconversion rates among health sciences students in the southeastern United States.

OBJECTIVE: To investigate the hepatitis B virus (HBV) seroconversion rate among health sciences students. PARTICIPANTS: The study included pharmacy, doctor of nursing, and medical students over 18 years of age enrolled at the University of South Carolina between 2007 and 2011. METHODS: The primary end point was HBV seroconversion rates among students at the initial reporting period. Seroconversion was defined as hepatitis B surface antibody (anti-HBs) level greater than or equal to 10 mIU/mL. Multivariate regression analysis was used to determine predictive factors of seroconversion. RESULTS: Of 777 records, data were available for 709 students. An 83.9% seroconversion rate was observed after a mean of 10 years between vaccine receipt and anti-HBs evaluation. Students with incomplete HBV vaccine series and longer time between initial series and evaluation were less likely to exhibit antibody response. CONCLUSIONS: These data highlight the importance of assessment and documentation of HBV vaccination series among health sciences students prior to direct patient care activities.

The association between sedentary behaviors during weekdays and weekend with change in body composition in young adults.

BACKGROUND: High sedentary time has been considered an important chronic disease risk factor but there is only limited information on the association of specific sedentary behaviors on weekdays and weekend-days with body composition. The present study examines the prospective association of total sedentary time and specific sedentary behaviors during weekdays and the weekend with body composition in young adults. METHODS: A total of 332 adults (50% male; 27.7 ± 3.7 years) were followed over a period of 1 year. Time spent sedentary, excluding sleep (SED), and in physical activity (PA) during weekdays and weekend-days was objectively assessed every 3 months with a multi-sensor device over a period of at least 8 days. In addition, participants reported sitting time, TV time and non-work related time spent at the computer separately for weekdays and the weekend. Fat mass and fat free mass were assessed via dual x-ray absorptiometry and used to calculate percent body fat (%BF). Energy intake was estimated based on TDEE and change in body composition. RESULTS: Cross-sectional analyses showed a significant correlation between SED and body composition (0.18 ≤ r ≤ 0.34). Associations between body weight and specific sedentary behaviors were less pronounced and significant during weekdays only (r ≤ 0.16). Nevertheless, decrease in SED during weekends, rather than during weekdays, was significantly associated with subsequent decrease in %BF (ß = 0.06, p <0.01). After adjusting for PA and energy intake, results for SED were no longer significant. Only the association between change in sitting time during weekends and subsequent %BF was independent from change in PA or energy intake (ß%BF = 0.04, p = 0.01), while there was no significant association between TV or computer time and subsequent body composition. CONCLUSIONS: The stronger prospective association between sedentary behavior during weekends with subsequent body composition emphasizes the importance of leisure time behavior in weight management.

The Prospective Association between Different Types of Exercise and Body Composition.

PURPOSE: Despite the widely accepted benefits of exercise on chronic disease risk, controversy remains on the role of exercise in weight loss. This study examined the effect of different exercise types on measures of adiposity across different fat categories. METHODS: A total of 348 young adults (49% male; 28 ± 4 yr), participating in an ongoing observational study provided valid data over a period of 12 months. Fat mass (FM) and lean mass (LM) were measured via dual x-ray absorptiometry every 3 months. Percent body fat was calculated and used to differentiate between normal-fat, "overfat," and obese participants. At each measurement time point, participants reported engagement (min·wk) in aerobic exercise, resistance exercise, and other forms of exercise. RESULTS: Most participants (93%) reported some exercise participation during the observation period. Total exercise or specific exercise types did not significantly affect subsequent body mass index after adjusting for sex, ethnicity, age, and baseline values of adiposity and exercise. Resistance exercise affected LM (P < 0.01) and FM (P < 0.01), whereas aerobic exercise only affected FM (P < 0.01). Any exercise type positively affected LM in normal-fat participants (P < 0.04). In overfat and obese participants, FM was reduced with increasing resistance exercise (P ≤ 0.02) but not with aerobic exercise (P ≥ 0.09). Additionally adjusting for objectively assessed total physical activity level did not change these results. CONCLUSIONS: Despite the limited effects on body mass index, exercise was associated with beneficial changes in body composition. Exercise increased LM in normal-fat participants and reduced FM in overfat and obese adults. Adults with excess body fat may benefit particularly from resistance exercise.