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1.
Psychol Health ; : 1-22, 2023 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-37592811

RESUMEN

Self-monitoring weight is commonly recommended for higher-weight women with a history of breast cancer, despite evidence demonstrating potentially negative psychological consequences of frequent self-weighing. The extent to which higher-weight women with breast cancer experience emotional and behavioral consequences in response to daily self-weighing is unknown. In this pilot study, women (n = 51) with a history of breast cancer in a behavioral weight management program completed a weeklong daily diary protocol. Participants were asked to self-weigh every morning and report on subsequent weight-related shame and guilt, and end-of-day engagement in compensatory exercise, diet, and purging behaviors. Women reported higher levels of guilt on days when their body weight was higher than usual, and when there was more discrepancy between their current vs. goal weight. Additionally, women engaged in higher levels of compensatory diet behavior on days when they experienced more weight-related guilt than usual. Based on these preliminary findings, daily self-weighing may be associated with harmful emotional and behavioral consequences among higher-weight women with a history of breast cancer.

2.
J Sports Sci ; 40(7): 733-741, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34930103

RESUMEN

This study explored how athletes' symptoms of mental disorders changed over the course of pandemic year. Predictors of baseline levels and changes in symptoms of mental disorders were also examined. Surveys were completed four times throughout a year by Canadian athletes training for the 2020 Olympics/Paralympics (ntime1 = 186, ntime2 = 142, ntime3 = 123, ntime4 = 108). Surveys included demographics questions, measures of perceived stress, training load, social support, coping, self-esteem, depression, anxiety, and disordered eating. Data were analysed using descriptive statistics and latent growth modelling. The prevalence of mental disorder symptoms was high at baseline and there was no significant change over time. Scores for the three disorders were significantly correlated. Female athletes had higher scores for disordered eating at baseline. Higher levels of perceived stress predicted higher scores on mental disorder measures. Longitudinal tracking of symptoms of mental disorders among elite athletes is important because it allows researchers to explore whether disorder symptomologies change; rates of mental disorder symptoms were high at baseline and stayed high over the course of a year. More research is needed to explore possible gender differences in rates of disorder symptoms, and to understand how those symptoms change over time.


Asunto(s)
Depresión , Salud Mental , Ansiedad/epidemiología , Atletas/psicología , Canadá/epidemiología , Depresión/epidemiología , Femenino , Humanos
3.
Brain Behav Immun Health ; 10: 100180, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34589720

RESUMEN

BACKGROUND: Breast cancer survivors (BCS) can exhibit a dysregulation of cortisol and elevated C-reactive protein (CRP) levels post-treatment, which increase the risk of diverse health outcomes. Certain behavioural, physical, and psychological variables may help to predict cortisol and CRP levels post-treatment. The aims of this study were to: (1) describe naturally occurring changes in absolute diurnal cortisol and CRP levels over a period of 1.5 years post-treatment among BCS, (2) assess if absolute diurnal cortisol and CRP levels change in tandem, and (3) assess behavioural, physical, and psychological variables as predictors of absolute diurnal cortisol levels and CRP levels. METHODS: Capillary blood and saliva samples were collected from 201 BCS, on average, 3.5 months post-treatment (T1) and again 3, 6, 9, and 12 months later (T2-T5). At each time point, five saliva samples were collected on two nonconsecutive days: at awakening, 30 â€‹min after awakening, 2:00 p.m., 4:00 p.m., and at bedtime. At each time point, participants also completed self-report questionnaires and wore an accelerometer for seven consecutive days. Data were analyzed using multilevel modeling. RESULTS: Absolute diurnal cortisol levels did not change significantly over time. CRP levels decreased across time points (B linear â€‹= â€‹-0.31, p â€‹= â€‹.01), though the rate of decrease slowed over time (B quadratic â€‹= â€‹0.05, p â€‹= â€‹.03). Generally, greater sedentary time predicted higher overall absolute diurnal cortisol levels (B â€‹< â€‹0.01, p â€‹= â€‹.01); whereas higher physical activity (B â€‹= â€‹-0.004, p â€‹< â€‹.01), lower body mass index (B â€‹= â€‹0.10, p â€‹< â€‹.01), and lower health- and cancer-related stress (B â€‹= â€‹0.24, p â€‹= â€‹.04) predicted lower overall CRP levels. Also, lower absolute diurnal cortisol levels were evident when participants engaged in more sedentary time, as compared to their own average sedentary time (B â€‹= â€‹-0.01, p â€‹< â€‹.01). CONCLUSIONS: Results offer insight into the nature of change in diurnal cortisol and CRP levels among BCS from treatment completion onwards and offer clinical implications. Helping BCS manage their weight, reduce stress, increase physical activity participation, and decrease sedentary time as soon as possible after treatment may help to reduce physiological dysregulations, thereby lowering the risk of adverse health outcomes in this population. Further research investigating specific intervention parameters such as type, context, frequency, and intensity are warranted for the development of the most optimal interventions.

4.
Obes Sci Pract ; 6(4): 365-372, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32874671

RESUMEN

INTRODUCTION: A substantial proportion of individuals with overweight or obesity perceive themselves as 'too heavy' relative to 'about right'. Perceiving one's weight as 'too heavy' is associated with lower levels of physical activity and higher levels of sedentary behaviour. However, the mechanisms underpinning the associations between weight perception and lifestyle behaviours have not been identified. Based on theoretical tenets and empirical evidence, the self-conscious emotions of shame and guilt may mediate these associations. METHODS: Participants were young adults (n = 618, Mage = 24.0 ± .6 years) who provided data on weight, weight perception, body-related shame and guilt, physical activity and screen time. RESULTS: Mediation analyses using the PROCESS macro indicated that shame and guilt significantly mediated the relationships between weight perception and physical activity and shame significantly mediated the relationship between weight perception and screen time. CONCLUSIONS: These findings provide preliminary evidence that self-conscious emotions may be mechanisms by which weight perception influences physical activity and sedentary behaviour in young adults. However, longitudinal investigations of this mechanism are needed.

5.
Breast Cancer ; 27(6): 1096-1106, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32488733

RESUMEN

BACKGROUND: Breast cancer survivors (BCS) may exhibit dysregulated patterns of cortisol and C-reactive protein (CRP). The aims of this study were to describe BCS' cortisol and CRP levels over a 1-year period after treatment, and assess how levels relate to socio-demographic- (age, education level, marital status), health- (body mass index [BMI] category, menopausal status), and cancer-related factors (cancer stage, chemotherapy exposure, time since diagnosis). METHODS: Participants (N = 201) provided data at 3 months post-treatment (T1) and again 3, 6, 9, and 12 months later (T2-T5). At T1, participants completed self-report questionnaires and had their weight and height measured by a trained technician. At T1-T5, they provided five saliva samples at awakening, 30 min after awakening, 2:00 pm, 4:00 pm, and before bedtime on two nonconsecutive days to measure diurnal cortisol, and provided capillary whole blood to measure CRP. Data were analyzed using repeated-measure analyses of variance (ANOVAs) and mixed-design ANOVAs. RESULTS: Diurnal cortisol and CRP levels fluctuated over time. In univariate models, older age and post-menopausal status were associated with higher cortisol and CRP levels, higher cancer stage and chemotherapy were associated with lower cortisol levels, and higher BMI category was associated with higher CRP levels. In adjusted models, age was no longer associated with CRP levels and shorter time since diagnosis was significantly associated with higher CRP levels. CONCLUSIONS: Socio-demographic-, health-, and cancer-related factors may help identify BCS at risk of physiological dysregulation who need intervention. Identifying modifiable factors associated with cortisol and CRP will inform cancer care interventions.


Asunto(s)
Neoplasias de la Mama/psicología , Proteína C-Reactiva/análisis , Supervivientes de Cáncer/psicología , Hidrocortisona/análisis , Estrés Psicológico/diagnóstico , Adulto , Factores de Edad , Anciano , Índice de Masa Corporal , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/terapia , Quimioterapia Adyuvante , Femenino , Humanos , Estudios Longitudinales , Mastectomía/psicología , Persona de Mediana Edad , Estadificación de Neoplasias , Factores de Riesgo , Saliva/química , Factores Socioeconómicos , Estrés Psicológico/inmunología , Estrés Psicológico/psicología , Estrés Psicológico/orina , Supervivencia , Factores de Tiempo
6.
Body Image ; 32: 24-33, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31734408

RESUMEN

The current study explored change in body-related self-conscious emotions (e.g., shame, guilt, authentic pride, hubristic pride) over three years, and tested body surveillance, age, weight status, years in sport, and competitive status as baseline predictors of change. Adolescent females engaged in organized sport (N = 518 at baseline, Mage = 14.02, SD = 1.38 years) completed a self-report survey once a year for three years (n = 293 and n = 215 in Years 2 and 3, respectively). Based on the unconditional latent growth model, body-related shame and guilt increased over time, and authentic and hubristic pride decreased over time. There was substantial between-person variability in the intercepts for all emotions and slopes for shame, guilt, and hubristic pride. In the conditional parallel process latent growth model, body surveillance predicted shallower change in shame and guilt over time. Female athletes high in body surveillance also reported higher body-related shame and guilt and lower authentic and hubristic pride at baseline. These findings highlight the importance of studying changes in self-conscious emotions over time in sport, and demonstrate that body surveillance may be an important factor to explore in interventions early in development.


Asunto(s)
Atletas/psicología , Imagen Corporal/psicología , Emociones , Deportes Juveniles/psicología , Adolescente , Femenino , Humanos , Estudios Longitudinales , Autoinforme
7.
J Sports Sci ; 37(21): 2459-2466, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31288678

RESUMEN

Perceptions of physical self-concept are critical to physical activity participation. In line with the reciprocal effects model of causal ordering (REM), higher perceptions of physical self-concept can function as a facilitator to physical activity, and can arise as a result of engaging in physical activity. While this relationship has been predominantly tested in physical activity contexts, directional tests between physical self-concept and sport specific outcomes are limited. The current study aimed to evaluate the generalizability of the REM to sport commitment and physical self-concept in youth athletes. Over 24 months, adolescent females (N = 215) completed self-report questionnaires at Time 1 (T1) and two years later (Time 2; T2). Using structural equation modeling, the reciprocal effects model demonstrated that the path leading from T1 physical self-concept to T2 sport commitment was significant (p = .02), whereas the path leading from T1 sport commitment to T2 physical self-concept was not significant (p = .23). The results suggest a unidirectional relationship and may underscore the importance of focusing on the physical self-concept in the development of strategies geared towards improving adolescent female's sport participation.


Asunto(s)
Autoimagen , Deportes/psicología , Adolescente , Niño , Ejercicio Físico/psicología , Femenino , Humanos , Estudios Longitudinales , Estudios Prospectivos , Autoinforme , Encuestas y Cuestionarios
8.
Curr Oncol ; 25(5): e365-e372, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30464686

RESUMEN

Background: Up to 90% of breast cancer survivors report low levels of physical activity (pa) and spend approximately 70% of the day in sedentary behaviour. Survivors might not be receiving information about the health benefits of pa and the consequences of sedentary behaviour in the context of their cancer. The primary purpose of the present study was to evaluate cancer centres for pa and sedentary behaviour information and infrastructure. A secondary aim was to evaluate the quality of the information that is accessible to breast cancer survivors in cancer centres. Methods: A built-environment scan of the 14 regional cancer centres in Ontario and an evaluation of the text materials about pa available at the cancer centres were completed. Data analyses included descriptive statistics, proportions, and inter-rater reliability. Results: The infrastructure of the cancer centres provided few opportunities for dissemination of information related to pa through signs and printed notices. Televisions were present in all waiting rooms, which could provide a unique opportunity for dissemination of information about pa and sedentary behaviour. Text materials were rated as trustworthy, used some behaviour change techniques (for example, information about the consequences of lack of pa, barrier identification, and setting graded tasks), and were aesthetically pleasing. Conclusions: These findings represent areas for knowledge dissemination both for the centre and for resources that could be further improved.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Ejercicio Físico , Educación del Paciente como Asunto , Conducta Sedentaria , Instituciones Oncológicas , Femenino , Conductas Relacionadas con la Salud , Humanos , Difusión de la Información , Ontario
9.
Curr Oncol ; 25(2): 149-162, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29719431

RESUMEN

Recent guidelines concerning exercise for people with cancer provide evidence-based direction for exercise assessment and prescription for clinicians and their patients. Although the guidelines promote exercise integration into clinical care for people with cancer, they do not support strategies for bridging the guidelines with related resources or programs. Exercise program accessibility remains a challenge in implementing the guidelines, but that challenge might be mitigated with conceptual frameworks ("pathways") that connect patients with exercise-related resources. In the present paper, we describe a pathway model and related resources that were developed by an expert panel of practitioners and researchers in the field of exercise and rehabilitation in oncology and that support the transition from health care practitioner to exercise programs or services for people with cancer. The model acknowledges the nuanced distinctions between research and exercise programming, as well as physical activity promotion, that, depending on the available programming in the local community or region, might influence practitioner use. Furthermore, the pathway identifies and provides examples of processes for referral, screening, medical clearance, and programming for people after a cancer diagnosis. The pathway supports the implementation of exercise guidelines and should serve as a model of enhanced care delivery to increase the health and well-being of people with cancer.


Asunto(s)
Vías Clínicas/organización & administración , Terapia por Ejercicio/organización & administración , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Neoplasias/rehabilitación , Alberta , Continuidad de la Atención al Paciente/organización & administración , Ejercicio Físico , Terapia por Ejercicio/estadística & datos numéricos , Humanos
10.
Curr Oncol ; 24(6): e477-e485, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29270056

RESUMEN

BACKGROUND: Cancer centre Web sites can be a useful tool for distributing information about the benefits of physical activity for breast cancer (bca) survivors, and they hold potential for supporting health behaviour change. However, the extent to which cancer centre Web sites use evidence-based behaviour change techniques to foster physical activity behaviour among bca survivors is currently unknown. The aim of our study was to evaluate the presentation of behaviour-change techniques on Canadian cancer centre Web sites to promote physical activity behaviour for bca survivors. METHODS: All Canadian cancer centre Web sites (n = 39) were evaluated by two raters using the Coventry, Aberdeen, and London-Refined (calo-re) taxonomy of behaviour change techniques and the eEurope 2002 Quality Criteria for Health Related Websites. Descriptive statistics were calculated. RESULTS: The most common behaviour change techniques used on Web sites were providing information about consequences in general (80%), suggesting goal-setting behaviour (56%), and planning social support or social change (46%). Overall, Canadian cancer centre Web sites presented an average of M = 6.31 behaviour change techniques (of 40 that were coded) to help bca survivors increase their physical activity behaviour. Evidence of quality factors ranged from 90% (sites that provided evidence of readability) to 0% (sites that provided an editorial policy). CONCLUSIONS: Our results provide preliminary evidence that, of 40 behaviour-change techniques that were coded, fewer than 20% were used to promote physical activity behaviour to bca survivors on cancer centre Web sites, and that the most effective techniques were inconsistently used. On cancer centre Web sites, health promotion specialists could focus on emphasizing knowledge mobilization efforts using available research into behaviour-change techniques to help bca survivors increase their physical activity.

13.
J Cancer Surviv ; 6(4): 359-71, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22777364

RESUMEN

PURPOSE: The impact of cancer and cancer treatment on the long-term health and quality of life of survivors is substantial, leading to questions about the most appropriate configuration of services and models of care for follow-up of post-primary treatment survivors. METHODS: A systematic review and quality appraisal of the health literature for structure of services and models of follow-up care for post-treatment survivors was identified through a search of guideline sources and empirical databases including MEDLINE, EMBASE, PsycINFO, the Cochrane Library, CINAHL, and EBSCO from 1999 through December 2009. RESULTS: Ten practice guidelines and nine randomized controlled trials comprised the evidence base for models of care for adult cancer survivors. Although the evidence base was rated as low quality, nurse-led and primary care physician models of follow-up care were equivalent for detecting recurrence. Consensus also suggests that cancer survivors may benefit from coordinated transition planning that includes the provision of survivorship care plans as part of standard care. CONCLUSIONS: Realignment of models of care is identified as a health system priority to meet the supportive care and surveillance needs of a burgeoning survivor population. Further research is needed to evaluate the efficacy of models of care in a broader population of cancer survivors with differing needs and risks. While the evidence is limited, there is research that may be used to guide the configuration of health care services and planning.


Asunto(s)
Continuidad de la Atención al Paciente/organización & administración , Modelos Organizacionales , Neoplasias/terapia , Proyectos de Investigación , Sobrevivientes , Adulto , Atención a la Salud/organización & administración , Estudios de Seguimiento , Necesidades y Demandas de Servicios de Salud , Humanos , Neoplasias/mortalidad , Proyectos de Investigación/estadística & datos numéricos , Apoyo Social , Sobrevivientes/estadística & datos numéricos
14.
Pediatr Obes ; 7(1): 73-81, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22434741

RESUMEN

OBJECTIVE: The objective of the study was to test the hypothesis that greater fluctuations in physical activity lead to greater increases in body fat during adolescence. METHODS: Seven hundred fifty-six adolescents in Montreal, Canada, aged 12-13 years at baseline, completed a 7-d physical activity recall questionnaire every 3 months over 5 years. Body mass index (BMI), waist circumference, and triceps and subscapular skinfold thickness were measured at baseline and at the end of follow-up. Subject-specific linear regressions, expressing physical activity as a function of time, were fitted and physical activity fluctuation scores were obtained by averaging the absolute values of regression residuals. The association between body fat after 5 years and the physical activity fluctuation score was assessed in linear regressions adjusting for baseline body fat, average number of physical activity sessions per week, diet and sociodemographic variables. RESULTS: Among boys, there were statistically significant positive associations between physical activity fluctuation and BMI (ß, 95% confidence interval: 0.12, 0.02-0.21) and triceps skinfold (0.40, 0.17-0.63). The associations with waist circumference or subscapular skinfold were not statistically significant (0.22, -0.04-0.49; 0.13, -0.05-0.32, respectively). In girls, there were statistically significant negative associations between physical activity fluctuation and BMI (-0.12, -0.20 to -0.03), waist circumference (-0.54, -0.91 to -0.17), subscapular skinfold (-0.41, -0.56 to -0.26) and triceps skinfold (-0.22, -0.38 to -0.05). CONCLUSION: Physical activity fluctuations appear to affect body fat during adolescence. Sex-specific interventions may be needed given that greater physical activity fluctuations seem unfavourable for boys and beneficial for girls.


Asunto(s)
Tejido Adiposo/metabolismo , Índice de Masa Corporal , Ejercicio Físico/fisiología , Tejido Adiposo/crecimiento & desarrollo , Adolescente , Composición Corporal/fisiología , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Modelos Lineales , Estudios Longitudinales , Masculino , Factores Sexuales , Grosor de los Pliegues Cutáneos , Circunferencia de la Cintura
15.
Eur Addict Res ; 18(2): 76-82, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22189160

RESUMEN

BACKGROUND/AIMS: We investigated the psychometric properties of a German translation of the 12-item Autonomy over Tobacco Scale (AUTOS) among 1,195 eighth-grade students. METHODS: Data for this study were collected as part of the fourth wave of data collection of the Smokefree Class Competition intervention in the Saxony-Anhalt region of Germany. Students from the control arm of the Smokefree Class Competition study who indicated that they had ever smoked 'at least a few puffs' on a cigarette were classified as ever-smokers. They self-completed questionnaires distributed by teachers. RESULTS: AUTOS scores ranged from 0 to 36 with a distribution highly skewed toward lower-response categories. Inter-item correlations ranged from 0.65 to 0.89 (mean = 0.79, SD = 0.06). Composite reliability for the AUTOS was high (Ω = 0.96) and 3 lower-order factors were also reliable (withdrawal: 0.89, psychological dependence: 0.91, cue-induced cravings: 0.87). Concurrent validity was supported by strong relationships between the AUTOS and both lifetime cigarette consumption and current smoking frequency. Youths were 18 times more likely to be current smokers (95% CI = 11.9-27.2, p < 0.001) if they endorsed any AUTOS item. CONCLUSION: The German AUTOS is reliable and valid, and the results are consistent with the English AUTOS for use with adolescents.


Asunto(s)
Fumar/psicología , Adolescente , Análisis Factorial , Femenino , Alemania/epidemiología , Humanos , Masculino , Autonomía Personal , Escalas de Valoración Psiquiátrica/normas , Psicometría , Reproducibilidad de los Resultados , Fumar/epidemiología , Encuestas y Cuestionarios
16.
Curr Oncol ; 18(6): e265-81, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22184494

RESUMEN

OBJECTIVE: Our goal was to develop evidence-based recommendations for the organization and structure of cancer survivorship services, and best-care practices to optimize the health and well-being of post-primary treatment survivors. This review sought to determine the optimal organization and care delivery structure for cancer survivorship services, and the specific clinical practices and interventions that would improve or maximize the psychosocial health and overall well-being of adult cancer survivors. DATA SOURCES: We conducted a systematic search of the Inventory of Cancer Guidelines at the Canadian Partnership Against Cancer, the U.S. National Guideline Clearinghouse, the Canadian Medical Association InfoBase, medline (ovid: 1999 through November 2009), embase (ovid: 1999 through November 2009), Psychinfo (ovid: 1999 through November 2009), the Cochrane Library (ovid; Issue 1, 2009), and cinahl (ebsco: 1999 through December 2009). Reference lists of related papers and recent review articles were scanned for additional citations. METHODS: Articles were selected for inclusion as evidence in the systematic review if they reported on organizational system components for survivors of cancer, or on psychosocial or supportive care interventions HOWELL et al. designed for survivors of cancer. Articles were excluded from the systematic review if they focused only on pediatric cancer survivor populations or on populations that transitioned from pediatric cancer to adult services; if they addressed only pharmacologic interventions or diagnostic testing and follow-up of cancer survivors; if they were systematic reviews with inadequately described methods; if they were qualitative or descriptive studies; and if they were opinion papers, letters, or editorials. DATA EXTRACTION AND SYNTHESIS: Evidence was selected and reviewed by three members of the Cancer Journey Survivorship Expert Panel (SM, TC, TKO). The resulting summary of the evidence was guided further and reviewed by the members of Cancer Journey Survivorship Expert Panel. Fourteen practice guidelines, eight systematic reviews, and sixty-thee randomized controlled trials form the evidence base for this guidance document. These publications demonstrate that survivors benefit from coordinated post-treatment care, including interventions to address specific psychosocial, supportive care, and rehabilitative concerns. CONCLUSIONS: Ongoing high-quality research is essential to optimize services for cancer survivors. Interventions that promote healthy lifestyle behaviours or that address psychosocial concerns and distress appear to improve physical functioning, psychosocial well-being, and quality of life for survivors.

17.
Health Educ Res ; 22(6): 782-93, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16987941

RESUMEN

The purpose of this study was to comprehensively assess the impact of school tobacco policy intention, implementation and students' perceptions of policy enforcement on smoking rates and location of tobacco use during the school day. Data were obtained from all students in Grades 10-11 (n = 22,318) in 81 randomly selected schools from five Canadian provinces. Policy intention was assessed by coding written school tobacco policies. School administrators most familiar with the tobacco policy completed a survey to assess policy implementation. Results revealed policy intention and implementation subscales did not significantly predict school smoking prevalence but resulted in moderate prediction of tobacco use on school property (R(2) = 0.21-0.27). Students' perceptions of policy enforcement significantly predicted school smoking prevalence (R(2) = 0.36) and location of tobacco use (R(2) = 0.23-0.63). The research findings emphasize: (i) the need to consider both written policy intention and actual policy implementation and (ii) the existence of a policy is not effective in controlling tobacco use unless the policy is implemented and is perceived to be strongly enforced.


Asunto(s)
Conducta del Adolescente/psicología , Instituciones Académicas/normas , Prevención del Hábito de Fumar , Políticas de Control Social , Estudiantes/psicología , Adolescente , Adulto , Canadá , Estudios Transversales , Humanos , Intención , Política Organizacional , Prevalencia , Desarrollo de Programa , Evaluación de Programas y Proyectos de Salud , Análisis de Regresión , Fumar/epidemiología , Fumar/tendencias , Encuestas y Cuestionarios
18.
Aviat Space Environ Med ; 70(6): 583-8, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10373050

RESUMEN

BACKGROUND: Ingesting a combination of caffeine and ephedrine (C+E) has been shown to raise metabolic heat production and body temperature. This side effect of C+E ingestion may be positive during a cold stress scenario, however, during heat stress it could prove to be detrimental. Thus, the purpose of this study was to clarify the effect of C+E ingestion on body temperature regulation during moderate exercise in a hot dry environment. METHODS: Ten, healthy, non heat acclimated, males exercised at 50% VO2peak in a 40 degrees C and 30% RH environment until rectal temperature reached 39.3 degrees C; heart rate (HR) remained at 95% of peak value or greater for 3 min, dizziness or nausea precluded further exercise, or 3 h had elapsed. They did this four times at weekly intervals: familiarization (Fam), control (Cont), placebo, and C+E (5 mg . kg(-1) caffeine + 1 mg . kg(-1) ephedrine) trials. The Fam and Cont treatments were done first and sequentially while the placebo and C+E treatments were balanced and double-blind. Tolerance times, mean skin temperature (Tsk), rectal temperature (Tre), Vo2, Vco2, VE, sweat rate (SR), HR, and sensation of thermal comfort were measured. RESULTS: Tolerance times (mean+/-SD in minutes) were similar for the placebo (120.0+/-28.4) and C+E (121.3+/-33.9) trials and both times were significantly longer than Cont (106.6+/-24.0) trial. C+E did not affect Tsk, initial TrC, delta Tre, SR or the sensation of thermal comfort. VO2 and VF, were significantly increased by C+E. HR was elevated by C+E compared with the other trials, but only during the initial 20 min of exercise. CONCLUSION: Although the metabolic rate was slightly increased with C+E treatment, it was sufficiently offset by increased heat loss mechanisms so that internal body temperature was not increased during moderate exercise in a hot, dry environment.


Asunto(s)
Regulación de la Temperatura Corporal/efectos de los fármacos , Cafeína/efectos adversos , Estimulantes del Sistema Nervioso Central/efectos adversos , Efedrina/efectos adversos , Ejercicio Físico/fisiología , Trastornos de Estrés por Calor/metabolismo , Trastornos de Estrés por Calor/fisiopatología , Resistencia Física/efectos de los fármacos , Adulto , Temperatura Corporal/efectos de los fármacos , Canadá , Método Doble Ciego , Quimioterapia Combinada , Prueba de Esfuerzo , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Personal Militar , Consumo de Oxígeno/efectos de los fármacos , Resistencia Física/fisiología , Factores de Tiempo
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