991 resultados para body cortisol


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Body image refers to an individual's internal representation ofhis/her outer self (Cash, 1994; Thompson, Heinberg, Altabe, & Tantleff-Dunn, 1999). It is a multidimensional construct which includes an individual's attitudes towards hislher own physical characteristics (Bane & McAuley, 1998; Cash, 1994; Cash, 2004; Davison & McCabe, 2005; Muth & Cash, 1997; Sabiston, Crocker, & Munroe-Chandler, 2005). Social comparison is the process of thinking about the self in relation to others in order to determine if one's opinions and abilities are adequate and to assess one's social status (Festinger, 1954; Wood, 1996). Research investigating the role of social comparisons on body image has provided some information on the types and nature of the comparisons that are made. The act of making social comparisons may have a negative impact on body image (van den Berg et ai., 2007). Although exercise may improve body image, the impact of social comparisons in exercise settings may be less positive, and there may be differences in the social comparison tendencies between non or infrequent exercisers and exercisers. The present study examined the nature of social comparisons that female collegeaged non or infrequent exercisers and exercisers made with respect to their bodies, and the relationship of these social comparisons to body image attitudes. Specifically, the frequency and direction of comparisons on specific tal-gets and body dimensions were examined in both non or infrequent exercisers and exercisers. Finally, the relationship between body-image attitudes and the frequency and direction with which body-related social comparisons were made for non or infrequent exercisers and exercisers were examined. One hundred and fifty-two participants completed the study (n = 70 non or ill infrequent exercisers; n = 82 exercisers). Participants completed measures of social physique anxiety (SPA), body dissatisfaction, body esteem, body image cognitions, leisure time physical activity, and social comparisons. Results suggested that both groups (non or infrequent exercisers and exercisers) generally made social comparisons and most frequently made comparisons with same-sex friends, and least frequently with same-sex parents. Also, both groups made more appearance-related comparisons than non-appearance-related comparisons. Further, both groups made more negative comparisons with almost all targets. However, non or infrequent exercisers generally made more negative comparisons on all body dimensions, while exercisers made negative comparisons only on weight and body shape dimensions. MANOV As were conducted to examine if any differences on social comparisons between the two groups existed. Results of the MANOVAs indicated that frequency of comparisons with targets, the frequency of comparisons on body dimensions, and direction of comparisons with targets did not differ based on exercise status. However, the direction of comparison of specific body dimensions revealed a significant (F (7, 144) = 3.26,p < .05; 1]2 = .132) difference based on exercise status. Follow-up ANOVAs showed significant differences on five variables: physical attractiveness (F (1, 150) = 6.33,p < .05; 1]2 = .041); fitness (F(l, 150) = 11.89,p < .05; 1]2 = .073); co-ordination (F(I, 150) = 5.61,p < .05; 1]2 = .036); strength (F(I, dO) = 12.83,p < .05; 1]2 = .079); muscle mass or tone (F(l, 150) = 17.34,p < .05; 1]2 = 1.04), with exercisers making more positive comparisons than non or infrequent exercisers. The results from the regression analyses for non or infrequent exercisers showed appearance orientation was a significant predictor of the frequency of social comparisons N (B = .429, SEB = .154, /3 = .312,p < .01). Also, trait body image measures accounted for significant variance in the direction of social comparisons (F(9, 57) = 13.43,p < .001, R2adj = .68). Specifically, SPA (B = -.583, SEB = .186, /3 = -.446,p < .01) and body esteem-weight concerns (B = .522, SEB = .207, /3 = .432,p < .01) were significant predictors of the direction of comparisons. For exercisers, regressions revealed that specific trait measures of body image significantly predicted the frequency of comparisons (F(9, 71) = 8.67,p < .001, R2adj = .463). Specifically, SPA (B = .508, SEB = .147, /3 = .497,p < .01) and appearance orientation (B = .457, SEB = .134, /3 = .335,p < .01) were significant predictors of the frequency of social comparisons. Lastly, for exercisers, the results for the regression of body image measures on the direction of social comparisons were also significant (F(9, 70) = 14.65,p < .001, R2adj = .609) with body dissatisfaction (B = .368, SEB = .143, /3 = .362,p < .05), appearan.ce orientation (B = .256, SEB = .123, /3 = .175,p < .05), and fitness orientation (B = .423, SEB = .194, /3 = .266,p < .05) significant predictors of the direction of social comparison. The results indicated that young women made frequent social comparisons regardless of exercise status. However, exercisers m,a de more positive comparisons on all the body dimensions than non or infrequent exercisers. Also, certain trait body image measures may be good predictors of one's body comp~son tendencies. However, the measures which predict comparison tendencies may be different for non or infrequent exercisers and exercisers. Future research should examine the effects of social comparisons in different populations (i.e., males, the obese, older adults, etc.). Implications for practice and research were discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The purpose of this study was to examine the associations between bone speed of sound (SOS) and body composition, osteoporosis-related health behaviours, and socioeconomic status (SES) in adolescent females. A total of 442 adolescent females in grades 9-11 participated. Anthropometric measures of height, body mass, and percent body fat were taken, and osteo-protective behaviours such as oral contraceptive use (OC), physical activity and daily calcium intake were evaluated using self-report questionnaires. Bone SOS was measured by transaxial quantitative ultrasound (QUS) at the distal radius and mid-tibia. The results suggest that fat mass is a significant negative predictor of tibial SOS, while lean mass is positively associated with radial SOS scores and calcium intake was positively associated with tibial SOS scores (p

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The current study investigated body image differences in post-menopausal women who self-reported having (SRO) or not having (SRN) osteoporosis and the impact of a 16-week exercise program on body image in these groups. Participants completed a measure of body image, and were randomly assigned to a 16-week exercise program or control group, stratified by self-reported osteoporosis status. After 16 weeks, they completed the same body image measure. There were no differences in body image between the two osteoporosis groups. The exercise intervention had a positive impact on body image for both the SRO and SRN groups. The exercise groups showed increases in fitness and health orientation and body areas satisfaction from baseline to 16-weeks, while the non-exercise group showed decreases in appearance and health evaluation, health orientation and body areas satisfaction. The results suggest an exercise program for post-menopausal women can lead to improvements in body image, regardless of osteoporosis status.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Although family eating practices (FEPs) playa role in the formation of eating practices in children, there is a lack of evidence regarding the role of FEPs on obesity (DB) risk. The purpose of this thesis was to assess the role of child, mother 'and father eating practices (CEPs; MEPS; FaEPs) on nutrient intakes, dietary patterns and body composition. Data were collected on approximately 2,400 peri-adolescents (s250 with complete covariate data). Dietary patterns were assessed using scores that reflected how closely participants followed DASH and Health Canada (HC) recommendations. In girls, poor CEPs, MEPs and FaEPs were associated with increased BMI and risk of overweight and poor dietary patterns according to DASH, and DASH and HC, respectively. In boys, poor CEPs and FaEPs were associated with increased monounsaturated and trans fat, and Vitamin C intakes, respectively. These findings suggest FEPs are associated with DB risk, particularly in girls.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Neuropeptides are the largest group of signalling chemicals that can convey the information from the brain to the cells of all tissues. DPKQDFMRFamide, a member of one of the largest families of neuropeptides, FMRFamide-like peptides, has modulatory effects on nerve-evoked contractions of Drosophila body wall muscles (Hewes et aI.,1998) which are at least in part mediated by the ability of the peptide to enhance neurotransmitter release from the presynaptic terminal (Hewes et aI., 1998, Dunn & Mercier., 2005). However, DPKQDFMRFamide is also able to act directly on Drosophila body wall muscles by inducing contractions which require the influx of extracellular Ca 2+ (Clark et aI., 2008). The present study was aimed at identifying which proteins, including the membrane-bound receptor and second messenger molecules, are involved in mechanisms mediating this myotropic effect of the peptide. DPKQDFMRFamide induced contractions were reduced by 70% and 90%, respectively, in larvae in which FMRFamide G-protein coupled receptor gene (CG2114) was silenced either ubiquitously or specifically in muscle tissue, when compared to the response of the control larvae in which the expression of the same gene was not manipulated. Using an enzyme immunoassay (EIA) method, it was determined that at concentrations of 1 ~M- 0.01 ~M, the peptide failed to increase cAMP and cGMP levels in Drosophila body wall muscles. In addition, the physiological effect of DPKQDFMRFamide at a threshold dose was not potentiated by 3-lsobutyl-1-methylxanthine, a phosphodiesterase inhibitor, nor was the response to 1 ~M peptide blocked or reduced by inhibitors of cAMP-dependent or cGMP-dependent protein kinases. The response to DPKQDFMRFamide was not affected in the mutants of the phosholipase C-~ (PLC~) gene (norpA larvae) or IP3 receptor mutants, which suggested that the PLC-IP3 pathway is not involved in mediat ing the peptide's effects. Alatransgenic flies lacking activity of calcium/calmodul in-dependent protein kinase (CamKII showed an increase in muscle tonus following the application of 1 JlM DPKQDFMRFamide similar to the control larvae. Heat shock treatment potentiated the response to DPKQDFMRFamide in both ala1 and control flies by approximately 150 and 100 % from a non heat-shocked larvae, respectively. Furthermore, a CaMKII inhibitor, KN-93, did not affect the ability of peptide to increase muscle tonus. Thus, al though DPKQDFMRFamide acts through a G-protein coupled FMRFamide receptor, it does not appear to act via cAMP, cGMP, IP3, PLC or CaMKl1. The mechanism through which the FMRFamide receptor acts remains to be determined.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of this study was to describe the nonlinear association between body mass index (BMI) and breast cancer outcomes and to determine whether BMI improves prediction of outcomes. A cohort of906 breast cancer patients diagnosed at Henry Ford Health System, Detroit (1985-1990) were studied. The median follow-up was 10 years. Multivariate logistic regression was used to model breast cancer recurrence/progression and breast cancer-specific death. Restricted cubic splines were used to model nonlinear effects. Receiver operator characteristic areas under the curves (ROC AUC) were used to evaluate prediction. BMI was nonlinearly associated with recurrence/progression and death (p= 0.0230 and 0.0101). Probability of outcomes increased with increase or decrease ofBMI away from 25. BMI splines were suggestive of improved prediction of death. The ROC AUCs for nested models with and without BMI were 0.8424 and 0.8331 (p= 0.08). I f causally associated, modifying patients BMI towards 25 may improve outcomes.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The current study examined the effect of two types of acute exercise (resistance and mind-body yoga) on state body image attitudes, to see which, was most effective at reducing body image concerns. I t was hypothesized that both types of exercise would lead to improvements in body image, with yoga showing the biggest benefits. Collegeaged female non/infrequent exercisers (n = 40) completed state measures of body satisfaction, social physique anxiety (SPA), and appearance orientation prior to and following participation in a single yoga and resistance class. Participation in the yoga class was associated with decreases in SPA and increases in body satisfaction. However, participation in the resistance class was associated with no changes in any of the study variables. These findings indicate participation in a single yoga class may have positive effects on body image attitudes, which may encourage non-exercisers to become more active.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Cardiovascular disease is a leading cause of mortality in the spinal cord injured (SCI) population. Reduced arterial compliance is a cardiovascular risk factor and whole body vibration (WBV) has be en shown to improve arterial compliance in able-bodied individuals. The study investigated the effect of an acute session ofWBV on arterial compliance as measured by pulse wave velocity (PWV). On separate days, arm, leg and aortic PWV were measured pre- and post- a 45 minute session of passive stance (PS) and WBV. The WBV was intermittent with a set frequency of 45Hz and amplitude of O.6mm. There was no condition by time effect when comparing PWV after WBV and PS. Following WBV, aortic (928.6±127.7 vs. 901.1±96.6cm/sec), leg (1035.2±113.8 vs.l099.8±114.2cm/sec) and arm PWV (1118.9±119.8 vs. 1181.1±124.4cm/s) did not change. As such, WBV did not reduce arterial compliance, however future research with protocol modifications is recommended.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

(A) Solid phase synthesis of oligonucleotides are well documented and are extensively studied as the demands continue to rise with the development of antisense, anti-gene, RNA interference, and aptamers. Although synthesis of RNA sequences faces many challenges, most notably the choice of the 2' -hydroxy protecting group, modified 2' -O-Cpep protected ribonucleotides were synthesized as alternitive building blocks. Altering phosphitylation procedures to incorporate 3' -N,N-diethyl phosphoramidites enhanced the overall reactivity, thus, increased the coupling efficiency without loss of integrety. Furthermore, technical optimizations of solid phase synthesis cycles were carried out to allow for successful synthesis of a homo UIO sequences with a stepwise coupling efficiency reaching 99% and a final yield of 91 %. (B) Over the past few decades, dipyrrometheneboron difluoride (BODIPY) has gained recognition as one of the most versatile fluorophores. Currently, BODIPY labeling of oligonucleotides are carried out post-synthetically and to date, there lacks a method that allows for direct incorporation of BODIPY into oligonucleotides during solid phase synthesis. Therefore, synthesis of BODIPY derived phosphoramidites will provide an alternative method in obtaining fluorescently labelled oligonucleotides. A method for the synthesis and incorporation of the BODIPY analogues into oligonucleotides by phosphoramidite chemistry-based solid phase DNA synthesis is reported here. Using this approach, BODIPY-labeled TlO homopolymer and ISIS 5132 were successfully synthesized.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The present set of experiments was designed to investigate the development of children's sensitivity of facial expressions observed within emotional contexts. Past research investigating both adults' and children's perception of facial expressions has been limited primarily to the presentation of isolated faces. During daily social interactions, however, facial expressions are encountered within contexts conveying emotions (e.g., background scenes, body postures, gestures). Recently, research has shown that adults' perception of facial expressions is influenced by these contexts. When emotional faces are shown in incongruent contexts (e.g., when an angry face is presented in a context depicting fear) adults' accuracy decreases and their reaction times increase (e.g., Meeren et a1. 2005). To examine the influence of emotional body postures on children's perception of facial expressions, in each of the experiments in the current study adults and 8-year-old children made two-alternative forced choice decisions about facial expressions presented in congruent (e.g., a face displayed sadness on a body displaying sadness) and incongruent (e.g., a face displaying fear on a body displaying sadness) contexts. Consistent with previous studies, a congruency effect (better performance on congruent than incongruent trials) was found for both adults and 8-year-olds when the emotions displayed by the face and body were similar to each other (e.g., fear and sad, Experiment l a ) ; the influence of context was greater for 8-year-olds than adults for these similar expressions. To further investigate why the congruency effect was larger for children than adults in Experiment 1 a, Experiment 1 b was conducted to examine if increased task difficulty would increase the magnitude of adults' congruency effects. Adults were presented with subtle facial and despite successfully increasing task difficulty the magnitude of the. congruency effect did not increase suggesting that the difference between children's and adults' congruency effects in Experiment l a cannot be explained by 8-year-olds finding the task difficult. In contrast, congruency effects were not found when the expressions displayed by the face and body were dissimilar (e.g., sad and happy, see Experiment 2). The results of the current set of studies are examined with respect to the Dimensional theory and the Emotional Seed model and the developmental timeline of children's sensitivity to facial expressions. A secondary aim of the series of studies was to examine one possible mechanism underlying congruency effe cts-holistic processing. To examine the influence of holistic processing, participants completed both aligned trials and misaligned trials in which the faces were detached from the body (designed to disrupt holistic processing). Based on the principles of holistic face processing we predicted that participants would benefit from misalignment of the face and body stimuli on incongruent trials but not on congruent trials. Collectively, our results provide some evidence that both adults and children may process emotional faces and bodies holistically. Consistent with the pattern of results for congruency effects, the magnitude of the effect of misalignment varied with the similarity between emotions. Future research is required to further investigate whether or not facial expressions and emotions conveyed by the body are perceived holistically.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study attempted to manipulate self-presentational efficacy to examine the effect on social anxiety, social physique anxiety, drive for muscularity, and maximal strength performance during a one-repetition maximum (1-RM) chest press and leg press test. Ninety-nine college men with a minimum of six months of previous weight training experience were randomly assigned to complete a 1-RM protocol with either a muscular male trainer described as an expert or a lean male trainer described as a novice. Participants completed measures of self-presentation and body image prior to meeting their respective trainer, and following the completion of the 1-RM tests. Although the self-presentational efficacy manipulation was not successful, the trainers were perceived significantly differently on musculature and expertise. The group with the muscular, expert trainer reported higher social anxiety and attained higher 1-RM scores for the chest and leg press. Thus, trainer characteristics can affect strength performance and self-presentational concerns in this population.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Anti-Black racism continues to be a widespread problem, and as such deserves investigation and elimination. As Jackson (2006) says; “There is a hyperawareness…of the negative inscriptions associated with the Black masculine body as criminal, angry and incapacitated.” (2) To continue the study of the changing face of racism, the researcher must be well equipped with a contemporary methodology which is adaptable and exploratory. Due to the malleability of racism, research into its elimination must make inroads to areas that have heretofore been neglected and overlooked by traditional academic study. This project achieves a unique perspective by undertaking a theoretical exploration of racist stereotypes and motifs in the world of mass produced superhero comic books, a genre of comics which has neither yet been thoroughly investigated for the use of racist stereotypes nor been the focus of anti-racist scholarship.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This mixed methods investigation examined the nutritional knowledge and habits of adolescent girls in grades 9 through 12 at a secondary school in southern Ontario. Through questionnaires, interviews, and the use of teaching and curriculum documents, this study attempted to understand whether the current nutrition curriculum is influential in developing students' nutritional knowledge, healthy eating habits, and a favourable body image. Data collection occurred over a 2-month period, involving 90 female participants, and the data analysis program SPSS was used for analysis of the quantitative questionnaire data. Interview data were organized into categories, and analysis of any emerging themes occurred. Teaching and curriculum documents were examined to determine any overlap and develop an understanding of the participants' exposure and experience within nutrition within the classroom setting. The findings of this study suggest that the current nutrition education did have an impact on the participants' nutrition knowledge. However, the impact on their eating habits and body image was limited in the context it was measured and tested. The knowledge learned within the classroom may not always be applied outside of the classroom. This study suggests that improvement in the current nutrition curriculum may be needed to have a bigger impact on adolescent females. The findings from the study shine light on areas of improvements for educators as well as development of future curriculum. Changes may need to be made not only in the specific curriculum content and expectations but also the delivery of it by the classroom teacher.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

There has been an increasing concern among researchers and the general population of our culture's increasing emphasis on "ideal" physical attractiveness-for both females and males. Despite this growing concern, research on body image has focused primarily on women and girls, with little research aimed specifically for males. Prior research (Grogan & Richards, 2002; Hargreaves & Tiggemann, 2006) stated that body image was a "feminine" or a "gay" issue, according to men and boys. The present study investigates this issue, particularly within the theoretical framework of multiple selves and gender theories. This exploratory case study involved semi-structured interviews with six male adolescents between the ages of 13 and 18 years. Researcher's fieldnotes were taken after the interviews. Content analysis of the interviews and fieldnotes revealed that for these six male adolescents, body image is not relevant to them, as they think about and discuss their issues of physical appearance with family and close peers. Traditional stereotypic notions of masculinity and what it means to be an adolescent male for the participants are discussed within the context of developmentally appropriate and gender-inclusive curriculum.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Previously, studies investigating emotional face perception - regardless of whether they involved adults or children - presented participants with static photos of faces in isolation. In the natural world, faces are rarely encountered in isolation. In the few studies that have presented faces in context, the perception of emotional facial expressions is altered when paired with an incongruent context. For both adults and 8- year-old children, reaction times increase and accuracy decreases when facial expressions are presented in an incongruent context depicting a similar emotion (e.g., sad face on a fear body) compared to when presented in a congruent context (e.g., sad face on a sad body; Meeren, van Heijnsbergen, & de Gelder, 2005; Mondloch, 2012). This effect is called a congruency effect and does not exist for dissimilar emotions (e.g., happy and sad; Mondloch, 2012). Two models characterize similarity between emotional expressions differently; the emotional seed model bases similarity on physical features, whereas the dimensional model bases similarity on underlying dimensions of valence an . arousal. Study 1 investigated the emergence of an adult-like pattern of congruency effects in pre-school aged children. Using a child-friendly sorting task, we identified the youngest age at which children could accurately sort isolated facial expressions and body postures and then measured whether an incongruent context disrupted the perception of emotional facial expressions. Six-year-old children showed congruency effects for sad/fear but 4-year-old children did not for sad/happy. This pattern of congruency effects is consistent with both models and indicates that an adult-like pattern exists at the youngest age children can reliably sort emotional expressions in isolation. In Study 2, we compared the two models to determine their predictive abilities. The two models make different predictions about the size of congruency effects for three emotions: sad, anger, and fear. The emotional seed model predicts larger congruency effects when sad is paired with either anger or fear compared to when anger and fear are paired with each other. The dimensional model predicts larger congruency effects when anger and fear are paired together compared to when either is paired with sad. In both a speeded and unspeeded task the results failed to support either model, but the pattern of results indicated fearful bodies have a special effect. Fearful bodies reduced accuracy, increased reaction times more than any other posture, and shifted the pattern of errors. To determine whether the results were specific to bodies, we ran the reverse task to determine if faces could disrupt the perception of body postures. This experiment did not produce congruency effects, meaning faces do not influence the perception of body postures. In the final experiment, participants performed a flanker task to determine whether the effect of fearful bodies was specific to faces or whether fearful bodies would also produce a larger effect in an unrelated task in which faces were absent. Reaction times did not differ across trials, meaning fearful bodies' large effect is specific to situations with faces. Collectively, these studies provide novel insights, both developmentally and theoretically, into how emotional faces are perceived in context.