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Fisheries that target sedentary shellfish present several challenges for deriving management reference points. Stock-recruit relationships often function at a relatively large spatial scale, with planktonic dispersal of eggs and larvae connecting discrete settlement areas, but postsettlement demographics are heterogeneous among local settlement areas. Another challenge is that information on age composition is not available for many invertebrates. Case studies of sedentary shellfish fisheries demonstrate a series of methods for estimating reference points. Biomass dynamics models may be an option for some data-limited fisheries, but inferences of metapopulation productivity can be confounded by serial depletion, so fishery and survey data should be explored for spatial patterns. Yield-per-recruit and eggs-per- recruit models can be size-based and spatially stratified. Demographic models of the full life cycle can integrate regional recruitment processes and postrecruitment processes at smaller spatial scales. Although metapopulation dynamics and spatial heterogeneity in postsettlement demographics can be accounted for in reference points, achieving the optimum yield of sedentary shellfish is largely conditional on managing spatial fishing patterns. KEY WORDS: benthic, shellfish, fisheries, management, reference points, INTRODUCTION Shellfish fisheries are valuable and substantially contribute to global fishery production (e.g., 25% of global consumption, FAO 2022). Worldwide landings of bivalves gradually increased from 0.8 million tons in [...]

Carbohydrates and lipids provide the majority of substrates to fuel mitochondrial oxidative phosphorylation. Metabolic inflexibility, defined as an impaired ability to switch between these fuels, is implicated in a number of metabolic diseases. Here, we explore the mechanism by which physical inactivity promotes metabolic inflexibility in skeletal muscle. We developed a mouse model of sedentariness, small mouse cage (SMC), that, unlike other classic models of disuse in mice, faithfully recapitulated metabolic responses that occur in humans. Bioenergetic phenotyping of skeletal muscle mitochondria displayed metabolic inflexibility induced by physical inactivity, demonstrated by a reduction in pyruvate- stimulated respiration ([JO.sub.2]) in the absence of a change in palmitate-stimulated [JO.sub.2]. Pyruvate resistance in these mitochondria was likely driven by a decrease in phosphatidylethanolamine (PE) abundance in the mitochondrial membrane. Reduction in mitochondrial PE by heterozygous deletion of phosphatidylserine decarboxylase (PSD) was sufficient to induce metabolic inflexibility measured at the whole-body level, as well as at the level of skeletal muscle mitochondria. Low mitochondrial PE in C2C12 myotubes was sufficient to increase glucose flux toward lactate. We further implicate that resistance to pyruvate metabolism is due to attenuated mitochondrial entry via mitochondrial pyruvate carrier (MPC). These findings suggest a mechanism by which mitochondrial PE directly regulates MPC activity to modulate metabolic flexibility in mice., Introduction Chronic physical inactivity increases all-cause mortality by 30%, accounting for one death every 44 seconds (1-4). Sedentary behavior exacerbates the risk for many chronic diseases, such as type 2 [...]

To reduce the number of sedentary people, an improved understanding of effects of exercise in this specific group is needed. The present project investigates the impact of regular aerobic exercise uptake on body image, and how this effect is associated with differences in interoceptive abilities and affective response to exercise. Participants were 29 sedentary adults who underwent a 12-week aerobic physical activity intervention comprised of 30-36 sessions. Body image was improved with large effect sizes. Correlations were observed between affective response to physical activity and body image improvement, but not with interoceptive abilities. Explorative mediation models suggest a neglectable role of a priori interoceptive abilities. Instead, body image improvement was achieved when positive valence was assigned to interoceptive cues experienced during exercise., Author(s): Duangkamol Srismith [sup.1] [sup.2] [sup.3] , Katja Dierkes [sup.4] , Stephan Zipfel [sup.1] , Ansgar Thiel [sup.4] , Gorden Sudeck [sup.4] , Katrin E. Giel [sup.1] , Simone C. [...]

Objectives Patterns of physical behaviors including physical activity, sedentary time, and sleep are unknown during pregnancy, but are likely to influence health outcomes. The purpose was to first identify 'physical behavior phenotypes' from accelerometer-measured physical behaviors in pregnant women during the first trimester and secondly, to explore the associations between the identified phenotypes with demographic variables and body-mass-index (BMI). Methods Data were from the Glowing Study (gov ID: NCT01131117), collected between 2011 and 2017 with accelerometer-measured physical behaviors of women in their 12th week of pregnancy. Latent class analysis was used to identify patterns of total physical activity, sleep time, sedentary time, and variation in physical activity. Maternal Body-Mass-Index (BMI). BMI and sociodemographic characteristics were compared between physical behavior phenotypes. Results A total of 212 pregnant women were included in the study (mean age 30.2 years (range 22.1 to 42.4), mean days wear 4.3 (SD 0.7)). Three physical behavior phenotypes were identified from the four physical behavior constructs: low sedentary and stable activity (n = 136, 64%), variable activity (n = 39, 18%), high sedentary and low sleep (n = 37, 17%). BMI, race, and education were significantly different between the three phenotypes, with the low sedentary and stable activity phenotype having the lowest BMI and a higher percentage of white and college educated women. Conclusions for Practice Total physical activity and physical behavior phenotypes during the first trimester were associated with early-pregnancy BMI, race, and education. Future research should examine whether these physical behavior phenotypes are associated with maternal and child health outcomes., Author(s): Erin K. Howie [sup.1] [sup.2] , Alexander Nelson [sup.3] , Joanne A. McVeigh [sup.2] [sup.4] , Aline Andres [sup.5] [sup.6] Author Affiliations: (1) https://ror.org/05jbt9m15, grid.411017.2, 0000 0001 2151 0999, [...]

This cross-sectional study aimed to explore the characteristics of cellphone use in Chinese early adolescents and the moderating and mediating role of self-control in the relationships among sedentary behavior, physical exercise, and cellphone use time. Using convenience sampling, we selected eight middle schools in Guangzhou, China. Two classes in the first grade of each middle school were randomly selected as the survey subjects. A total of 715 early adolescents (ages 11-13) completed surveys about the purpose of using cellphones (i.e., learning, entertainment, and others), cellphone use scenarios (i.e., sitting, standing, and moving), sedentary behavior, physical exercise, cellphone use time, and self-control. The results showed that the mean total daily cellphone use was 36.44 ± 37.42 min/day in early adolescents, who used cellphones mainly for studying, and 91.7% of them were seated when using cellphones. Cellphone use time was positively correlated with sedentary behavior, not correlated with physical exercise, and negatively correlated with self-control. Self-control played a moderating (not mediating) role not only between sedentary behavior and cellphone use time but also between physical exercise and cellphone use time. This study revealed the complex relationships among sedentary behavior, physical exercise, self-control, and cellphone use time. Our findings have significance for preventing the overuse of cellphones among early adolescents., Author(s): Ming-Qiang Xiang [sup.1] , Zi-Rong Wang [sup.2] , Zebo Xu [sup.1] , Peizhen Sun [sup.3] , Lanlan Zhang [sup.4] Author Affiliations: (1) grid.443378.f, 0000 0001 0483 836X, School of [...]

Study objective Different behaviors are considered important factors that may influence a healthy lifestyle. Given this fact, we aim to analyze the relationship between moderate-vigorous physical activity (MVPA), sleep time, and sedentary time, with cardiometabolic outcomes in adolescents. Methods Cross-sectional study, with 152 eutrophic and healthy adolescents. The behavioral variables were collected objectively and the arterial thickness was measured through ultrasound. Blood variables (LDL, TG, HDL, glucose, and insulin) were collected in a private laboratory. To analyze the data, the Student t test and Kruskal-Wallis test were used to compare the groups. All analyses adopted p < 0.05. Results Girls who demonstrated better combined behaviors, presented significant results for TG (p = 0.045), BP (p = 0.016), and cardiovascular score (p = 0.049) when compared to their peers. Furthermore, the practice of physical activity combined with sufficient sleep time was associated with lower values of arterial thickening (p = 0.017). Conclusions In view of the results presented, it is possible to state that the aggregation of behaviors was more consistent in females and that the practice of physical activity and adequate sleep time can reflect on cardiovascular health., Author(s): Andrea Wigna [sup.1] , Jacqueline B Urban [sup.1] , Wésley Torres [sup.1] , Lucas G Moraes-Chagas [sup.1] , Jefferson S Dias [sup.1] , David S Nunes [sup.1] , Veronica [...]

Understanding associations between mothers' and children's physical activity and sedentary behavior on more fine-grained timescales can provide insights into real-time intervention opportunities. This study examined the extent to which mothers' and their children's device-measured moderate-to-vigorous physical activity (MVPA) and sedentary time (SDT) were associated at the day level during non-school time. Mother-child dyads (N = 193; baseline Mean ages = 40.69 ± 6.11 [mother] and 9.57 ± 0.89 [child] years) provided 3,135 paired days of accelerometry data from six bi-annual waves across three years. Controlling for covariates, multilevel models revealed that mothers' and their children's MVPA and SDT were positively associated at the day level during non-school time, both on weekdays and weekends. During weekdays, the day-level association for SDT was stronger for older than younger children, and the day-level association for MVPA was stronger for boys than girls. Designing family-based interventions targeting school-age children and their mothers during non-school time across the week may be useful for promoting active lifestyles., Author(s): Chih-Hsiang Yang [sup.1] , Shirlene Wang [sup.2] , Wei-Lin Wang [sup.2] , Britni R. Belcher [sup.2] , Genevieve F. Dunton [sup.2] [sup.3] Author Affiliations: (1) grid.254567.7, 0000 0000 9075 [...]

Older children with Autism Spectrum Disorder (ASD) have high levels of motor impairment, however we are unsure if similar patterns exist in young children. This study aimed to investigate motor competence in four-to-seven-year-old children with (n = 17) and without (n = 17) ASD. A series of ANOVAS indicated children with ASD performed significantly poorer on all measures of motor competence, except MABC-2 manual dexterity and ball skills subscales. Results indicate that moderate-to-vigorous physical activity (PA) and sedentary behaviour (SB) may influence motor competence, regardless of diagnosis. Establishing appropriate levels of engagement in moderate-to-vigorous PA and SB during early school years is important for the development of all children and may be an important early intervention avenue for motor impairment in children with ASD., Author(s): S. Thomas [sup.1] , L. M. Barnett [sup.2] [sup.3] , N. Papadopoulos [sup.1] , N. Lander [sup.4] , J. McGillivray [sup.1] , N. Rinehart [sup.5] Author Affiliations: (1) grid.1021.2, [...]

Previous studies among adolescents conceptualize behavioral cognitions [e.g., intentions and perceived behavioral control (PBC)] as stable trait-like factors despite evidence suggesting they vary momentarily. We examined whether intentions and PBC momentarily relate to subsequent sedentary time during non-school periods. Healthy adolescents (N = 15, ages 11-15) reported their intentions and PBC regarding sedentary leisure behaviors via ecological momentary assessment (EMA) up to seven times/day for 14 days. Sedentary time in the two hours following each EMA prompt was measured by ActivPAL accelerometers. When participants reported greater sedentary intentions (within-person [beta] = 1.1, 95% CI 0.2, 2.1, p = 0.0213) and sedentary PBC (within-person [beta] = 1.7, 95% CI 0.6, 2.8, p = 0.0029), they accumulated greater sedentary time. This demonstrates that sedentary intentions and PBC are acutely associated with sedentary time among adolescents. Our findings highlight the potential for implementing just-in-time activity interventions among adolescents during at-risk periods within the day, characterized by deviations from one's usual intentions and PBC levels., Author(s): Shayan Ebrahimian [sup.1] , Jennifer Zink [sup.1] , Chih-Hsiang Yang [sup.2] , Qihan Yu [sup.1] , Kellie Imm [sup.1] , Michele Nicolo [sup.1] , Genevieve F. Dunton [sup.1] [sup.3] [...]

In Ghana, more than four in ten deaths in 2016 resulted from non-communicable diseases (NCDs). Physical inactivity and sedentary behaviours are important risk factors for NCDs. No previous systematic reviews examining physical activity and sedentary behaviour among Ghanaians were identified. Therefore, this rapid scoping review was conducted to find and synthesise what is known about the epidemiology of physical activity and sedentary behaviour of children and adults in Ghana. MEDLINE was searched for eligible studies and a narrative synthesis was conducted based on 17 identified papers as well as the 2008 Demographic and Health Survey report. Little recent high-quality data on prevalence of physical activity or sedentary behaviour in Ghana was found. Existing nationally representative data is now more than ten years old. The data identified suggest that the majority of Ghanaian adults, aged 18+ years, are physically active, achieving or exceeding World Health Organisation (WHO) recommendations (84.3% according to data collected in 2007-2008). Studies reporting sedentary behaviour in adults further suggest that the majority of Ghanaians are minimally sedentary. The most consistent associations with physical activity were by gender (men achieved more than women), employment (the employed, particularly in skilled manual jobs, achieved more than the unemployed), urban or rural residence (rural inhabitants achieved more than urban inhabitants) and socio-economic status (lower physical activity with increasing socio-economic status). Meanwhile, the few existing studies of physical activity in children (all of which investigated children aged 12+ years) suggest that the proportion of children achieving WHO recommendations on physical activity may be lower than for adults. A similar gender trend exists for children as in the adult data, with boys achieving more physical activity than girls. Physical activity is accrued most frequently through active travel, and active occupations, while leisure time physical activity is low. This means that the Ghanaian population may be vulnerable to becoming increasingly inactive as work and travel become more frequently mechanised and sedentary. Key words: Ghana, review, non-communicable disease, Epidemiology, Physical activity, behaviour, INTRODUCTION Globally non-communicable diseases (NCDs) like cancers and cardiovascular diseases (CVDs) are the leading cause of death [1]. According to the World Health Organisation (WHO), low-and-middle-income countries (LMICs) are disproportionately [...]