Key Beliefs for Targeted Interventions to Increase Physical Activity in Children: Analyzing Data from an Extended Version of the Theory of Planned Behaviour

Given the high prevalence of overweight and low levels of physical activity among children, a better understanding of physical activity behaviour is an important step in intervention planning. This study, based on the theory of planned behaviour, was conducted among 313 fifth graders and their parents. Children completed a computer-based questionnaire to evaluate theoretical constructs and behaviour. Additional information was obtained from parents by means of a questionnaire. Correlates of children's physical activity were intention and self-identity. Determinants of intention were self-efficacy, self-identity, and attitude. Parental variables were mediated through cognitions. Among girls, practicing sedentary activities was an additional negative determinant of intention. Key beliefs of boys and girls were related to time management and difficulties associated with physical activity. For girls, social identification as an active girl was another important belief related to positive intention. This study provides theory-based information for the development of more effective interventions aimed at promoting physical activity among children

Les déterminants de l'intention de pratiquer régulièrement des activités physiques chez les élèves de cinquième année du primaire

Tableau d'honneur de la Faculté des études supérieures et postdoctorales, 2006-200

Analyse technico-économique d'un système hybride éolien-photovoltaïque en comparaison avec les systèmes photovoltaïque et éolien seuls

Vu la grande superficie du territoire québécois, de nombreuses habitations sont isolées ou à une distance importante du réseau électrique, donc les coûts de raccordement au réseau sont gonflés et souvent, le raccordement est tout simplement impossible. Les systèmes autonomes sont donc intéressants pour alimenter en électricité les habitants de ces régions. L’utilisation de génératrices carburant aux énergies fossiles est la solution actuelle. Les systèmes seuls, éolien ou photovoltaïque, nécessitent beaucoup d’accumulateurs pour pallier à l’intermittence des gisements. Les systèmes hybrides autonomes avec des panneaux solaires photovoltaïques et des éoliennes sont donc une solution potentielle limitant l’intermittence des ressources. L’analyse de diverses combinaisons de systèmes est réalisée en situation hors réseau et connectée au réseau. L’hypothèse principale de ce travail est que si un système photovoltaïque est joint à un système éolien hors réseau au Québec, cela permet de diminuer les moments sans apport d’énergie, donc on diminue les possibilités d’intermittence du système. Ainsi, la quantité d’accumulateurs nécessaires peut être diminuée. Cette diminution du nombre d’accumulateurs et de la taille des systèmes installés se traduit en économies pour l’ensemble du système. L’objectif était de comparer des systèmes hybrides éoliens-photovoltaïques avec des systèmes photovoltaïque ou éolien seuls pour un site hors réseau au Québec et par rapport à d'autres sites ailleurs dans le monde. Par une comparaison, la situation actuelle (diésel et connectée au réseau) a aussi été étudiée. Dans un premier temps, les systèmes seuls sont étudiés. L’analyse des différentes combinaisons de systèmes hybrides hors réseau et connectée au réseau est effectuée. L’originalité du projet provient dans l’addition d’un système photovoltaïque à un système éolien dans un contexte québécois et hors réseau. Globalement, les systèmes seuls, éoliens ou photovoltaïques, sont une option moins viable que l’option des systèmes combinés utilisant ces deux énergies. En général, pour le cas des systèmes autonomes, il est économiquement rentable d’ajouter des éoliennes aux systèmes avec génératrice diésel. Si les coûts des équipements ou du diésel évoluent, l’ajout de panneaux solaires à ces systèmes sera justifié. Quand les coûts d’électricité auront légèrement augmentés et que les coûts de rachat de l’électricité par le réseau seront intéressants, l’ajout de panneaux solaires, d’éoliennes et de génératrices diésel au système sera rentable pour le particulier dans le cas de systèmes connectés au réseau. ---------- Given Quebec’s vastness, numerous homes are located in remote areas or considerably far away from the electric grid. Tying these homes to the grid is often very expensive or even impossible. Stand-alone systems are thus prime candidates to provide the energy requirements for the inhabitants of isolated locations. Currently, fossil fuel generators are the most widespread solutions. Wind- or photovoltaic-only systems require large amounts of batteries to compensate for the intermittence of resource availability. Stand-alone hybrid systems that combine both wind turbines and photovoltaic solar panels address this issue. Various combinations of both standalone and grid-connected systems are analysed. The premise of this work is that the addition of photovoltaic panels to a stand-alone wind-turbine system (in Quebec) will increase the system’s robustness to resource intermittence thereby reducing the number of required accumulators. This reduction coupled with the resulting reduction in overall system size would lead to monetary savings. The objective was to compare hybrid wind and photovoltaic systems with wind- and photovoltaic-only systems for a number of off-grid sites in Quebec and abroad. The results are compared with the current -- diesel and gridconnected – situation. This work’s contribution lies in the study of the coupling of photovoltaic systems with wind turbine systems in off-grid Quebec areas. Overall, wind- or photovoltaic-only systems are less viable that hybrid systems that use both technologies. For stand-alone systems, it is usually cost effective to add wind-turbines to diesel generator systems. If equipment or fuel costs were to increase, it would then become costeffective to also add solar panels. When the grid power price will have increased and sellback prices become worthwhile, adding solar panels, wind turbines and diesel generators to even gridtied systems will become cost-effective

Impacts des barrages sur les débits annuels minimums en fonction des régimes hydrologiques artificialisés au Québec (Canada)

Les débits annuels minimums des rivières déterminent le volume d’habitat minimum disponible pour assurer la survie des espèces aquatiques en période d’étiage. Dans cette étude, nous comparons les impacts de barrages sur les caractéristiques (période d’occurrence, magnitude, amplitude de variation et asymétrie) de ces débits dans trois régimes hydrologiques artificialisés d’une part, et les débits annuels minimums mesurés en aval des barrages aux normes de débits réservés pour protéger les habitats du poisson au Québec, d’autre part. Nous avons analysé 72 stations appartenant aux régimes artificialisés d’Inversion (26 stations), d’Homogénéisation (18 stations) et de Type Naturel (28 stations). Toutes ces stations appartiennent au bassin versant du fleuve Saint-Laurent. La présente analyse est fondée sur la comparaison des débits mesurés en rivières naturelles (75 stations) à ceux mesurés en aval des barrages au moyen des méthodes de proportionnalité et graphique. Il ressort de ces comparaisons les principaux résultats suivants.En régime artificialisé d’Inversion caractérisé par les débits mensuels maximums en hiver et les débits mensuels minimums au printemps, les impacts des barrages se traduisent par une hausse significative de fréquence des débits annuels minimums au printemps au moment de la fonte des neiges mais une baisse en été, une diminution significative de la magnitude des débits pour les bassins versants de taille 10 000 km2.Annual minimum discharges represent a crucial hydrologic parameter for the health of aquatic ecosystems. They determine the volume of available habitat for aquatic species and influence the concentration of pollutant within the fluvial system during low flows. They are also of importance for instream infrastructures and for the regulation of fluvial transport. For these reasons, the minimum discharges constitute the main hydrologic parameters for which clear regulation have been defined in several countries. In the province of Québec, albeit the large amount of dams on several important fluvial systems, there seems to exist a lack of studies examining their effects on the annual minimum discharges. This paper is aiming at highlighting the effects of dams (1) by examining their effect on the characteristics of annual minimum discharges for artificialised flow regimes in Québec, and (2) by comparing those discharges with recommended instream flows to protect fish habitats.Firstly, the effect of dams on annual minimum discharges is examined for the three types of artificialised flow regimes found in Québec. From the analysis of seasonal and monthly discharges, ASSANI et al. (2004) documented the three types of artificialised hydrologic regime downstream from dams: the inversion, the homogenization, and the natural type flow regimes. The inversion flow regime presents high monthly discharge values in winter and low monthly discharge values during spring. This type of regime occurs solely on the north shore of the St-Lawrence River and pertains to rivers with large reservoirs feeding in hydropower stations. The homogenization flow regime presents small annual fluctuations of the monthly discharge. The maximum monthly discharges are recorded during spring where- as the minimum monthly discharges frequently occur during fall. This type of regime is often associated with reservoirs created on large streams for which the storage of spring water is less important. This regime is observed mainly on the north shore of the St-Lawrence river. In the natural type flow regime, the maximum monthly discharges take place during spring snowmelt while minimum monthly discharges occur either during summer or winter. The annual natural flow characteristics are thus conserved albeit the existence of the dam. This regime pertains to dams with small reservoirs and it is found on both side of the St-Lawrence River.Secondly, annual mimimum discharges are compared with minimum instream flows recommended by BELZILE et al. (1997). These ones defined the minimum instream flows based on the different species of fish and their life cycle. Downstream from dams, the instream flows (Qr) can be estimated using the following relation:Qr = ek.Sawhere S represents the drainage area upstream from the dam; a and k are respectively regional and seasonal parameters. These parameters are associated to the ecohydrological region, to the season as well as to the critical phases of life cycle for the fish species found within the ecohydrological regions.From the Historical Stream Flow Summary of Environmental Canada, the distribution of discharge from 107 stations were selected and analysed. From those, 72 were located on rivers with dams and 75 on rivers with no regulation. On regulated rivers, 26, 18 and 28 were identified as belonging to the inversed, homogeneous and natural type regimes, respectively. All stations were located in the St-Lawrence drainage area. To highlight the effect of dams, we performed a comparison between the annual minimum discharges for stations on artificialised rivers to those from stations belonging to rivers with no regulation. The comparison is performed according to the size of the drainage basins (proportionality method) and uses a set of parametric and non-parametric statistical tests depending on the type of data. The proportionality method was chosen because of the non-availability of the discharges for the pre-dam periods. According to RICHTER et al. (1996), river flows can be described using several parameters relating to the daily discharges: the magnitude, the frequency, the duration, the timing and the rate of change (amplitude of the variability). The daily discharges required to compute these parameters were not available. The date of occurrence of annual minimum discharges, their magnitude, the interannual variability of the magnitude and the skewness of the distribution could however be obtained from the Historical Stream Flow Summary of Environmental Canada.The analysis of annual minimum discharges for the three types of artificialised flow regimes highlights several key elements associated with the effect of dams. For the inversion flow regime, the presence of dams increases and decreases significantly the occurrence of annual minimum discharges during spring and summer, respectively. For drainage area smaller than 10 000 km2, the magnitude of the annual minimum discharge is decreased significantly. Finally, the between-year variability is increased and the distribution presents a strong skewness. For the natural type flow regime, an increase in annual minimum discharges during the period between November and January can be observed as well as a significant decrease in magnitude for the small fluvial systems (drainage area 10 000 km2

The effect of mere-measurement of cognitions on physical activity behavior: a randomized controlled trial among overweight and obese individuals

<p>Abstract</p> <p>Background</p> <p>The promotion of physical activity among an overweight/obese population is an important challenge for clinical practitioners and researchers. In this regard, completing a questionnaire on cognitions could be a simple and easy strategy to increase levels of physical activity. Thus, the aim of the present study was to test the effect of completing a questionnaire based on the Theory of Planned Behavior (TPB) on the level of physical activity.</p> <p>Methods</p> <p>Overall, 452 overweight/obese adults were recruited and randomized to the experimental or control group. At baseline, participants completed a questionnaire on cognitions regarding their participation in leisure-time physical activity (experimental condition) versus a questionnaire on fruit and vegetable consumption (control condition). The questionnaires assessed the TPB variables that are beliefs, attitude, norm, perception of control, intention and a few additional variables from other theories. At three-month follow-up, leisure-time physical activity was self-reported by means of a short questionnaire. An analysis of covariance with baseline physical activity level as covariate was used to verify the effect of the intervention.</p> <p>Results</p> <p>At follow-up, 373 participants completed the leisure-time physical activity questionnaire. The statistical analysis showed that physical activity participation was greater among participants in the experimental condition than those in the control condition (<it>F</it>(1,370) = 6.85, <it>p </it>= .009, <it>d </it>= 0.20).</p> <p>Conclusions</p> <p>Findings indicate that completing a TPB questionnaire has a significant positive impact on subsequent participation in physical activity. Consequently, asking individuals to complete such a questionnaire is a simple, inexpensive and easy strategy to increase the level of physical activity among overweight/obese adults.</p

Promoting healthy eating in early pregnancy in individuals at risk of gestational diabetes mellitus: does it improve glucose homeostasis? A study protocol for a randomized control trial

BackgroundHealthy eating during pregnancy has favorable effects on glycemic control and is associated with a lower risk of gestational diabetes mellitus (GDM). According to Diabetes Canada, there is a need for an effective and acceptable intervention that could improve glucose homeostasis and support pregnant individuals at risk for GDM.AimsThis unicentric randomized controlled trial (RCT) aims to evaluate the effects of a nutritional intervention initiated early in pregnancy, on glucose homeostasis in 150 pregnant individuals at risk for GDM, compared to usual care.MethodsPopulation: 150 pregnant individuals ≥18 years old, at ≤14 weeks of pregnancy, and presenting ≥1 risk factor for GDM according to Diabetes Canada guidelines. Intervention: The nutritional intervention initiated in the first trimester is based on the health behavior change theory during pregnancy and on Canada’s Food Guide recommendations. It includes (1) four individual counseling sessions with a registered dietitian using motivational interviewing (12, 18, 24, and 30 weeks), with post-interview phone call follow-ups, aiming to develop and achieve S.M.A.R.T. nutritional objectives (specific, measurable, attainable, relevant, and time-bound); (2) 10 informative video clips on healthy eating during pregnancy developed by our team and based on national guidelines, and (3) a virtual support community via a Facebook group. Control: Usual prenatal care. Protocol: This RCT includes three on-site visits (10–14, 24–26, and 34–36 weeks) during which a 2-h oral glucose tolerance test is done and blood samples are taken. At each trimester and 3 months postpartum, participants complete web-based questionnaires, including three validated 24-h dietary recalls to assess their diet quality using the Healthy Eating Food Index 2019. Primary outcome: Difference in the change in fasting blood glucose (from the first to the third trimester) between groups. This study has been approved by the Ethics Committee of the Centre de recherche du CHU de Québec-Université Laval.DiscussionThis RCT will determine whether a nutritional intervention initiated early in pregnancy can improve glucose homeostasis in individuals at risk for GDM and inform Canadian stakeholders on improving care trajectories and policies for pregnant individuals at risk for GDM.Clinical trial registrationhttps://clinicaltrials.gov/study/NCT05299502, NCT0529950

Randomized controlled study of the effect of a butter naturally enriched in trans fatty acids on blood lipids in healthy women123

Background: Whereas the negative effect of consuming trans fatty acids found in partially hydrogenated vegetable oils on cardiovascular disease (CVD) risk is well established, the effect of trans fatty acids from ruminant sources (rTFAs) on CVD risk factors has not yet been established, particularly among women

Theory-based interventions combining mental simulation and planning techniques to improve physical activity: Null results from two randomized controlled trials

Interventions to assist individuals in initiating and maintaining regular participation in physical activity are not always effective. Psychological and behavioral theories advocate the importance of both motivation and volition in interventions to change health behavior. Interventions adopting self-regulation strategies that foster motivational and volitional components may, therefore, have utility in promoting regular physical activity participation. We tested the efficacy of an intervention adopting motivational (mental simulation) and volitional (implementation intentions) components to promote a regular physical activity in two studies. Study 1 adopted a cluster randomized design in which participants (n = 92) were allocated to one of three conditions: mental simulation plus implementation intention, implementation intention only, or control. Study 2 adopted a 2 (mental simulation vs. no mental simulation) × 2 (implementation intention vs. no implementation intention) randomized controlled design in which fitness center attendees (n = 184) were randomly allocated one of four conditions: mental simulation only, implementation intention only, combined, or control.Physical activity behavior was measured by self-report (Study 1) or fitness center attendance (Study 2) at 4- (Studies 1 and 2) and 19- (Study 2 only) week follow-up periods. Findings revealed no statistically significant main or interactive effects of the mental simulation and implementation intention conditions on physical activity outcomes in either study. Findings are in contrast to previous research which has found pervasive effects for both intervention strategies. Findings are discussed in light of study limitations including the relatively small sample sizes, particularly for Study 1, deviations in the operationalization of the intervention components from previous research and the lack of a prompt for a goal intention. Future research should focus on ensuring uniformity in the format of the intervention components, test the effects of each component alone and in combination using standardized measures across multiple samples, and systematically explore effects of candidate moderators

Are physical activity interventions for healthy inactive adults effective in promoting behavior change and maintenance, and which behavior change techniques are effective? A systematic review and meta-analysis

© The Author(s) 2018. Published by Oxford University Press on behalf of the Society of Behavioral Medicine. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected] inactivity and sedentary behavior relate to poor health outcomes independently. Healthy inactive adults are a key target population for prevention. This systematic review and meta-analysis aimed to evaluate the effectiveness of physical activity and/or sedentary behavior interventions, measured postintervention (behavior change) and at follow-up (behavior change maintenance), to identify behavior change techniques (BCT) within, and report on fidelity. Included studies were randomized controlled trials, targeting healthy inactive adults, aiming to change physical activity and/or sedentary behavior, with a minimum postintervention follow-up of 6 months, using 16 databases from 1990. Two reviewers independently coded risk of bias, the "Template for Intervention Description and Replication" (TIDieR) checklist, and BCTs. Twenty-six studies were included; 16 pooled for meta-analysis. Physical activity interventions were effective at changing behavior (d = 0.32, 95% confidence intervals = 0.16-0.48, n = 2,346) and maintaining behavior change after 6 months or more (d = 0.21, 95% confidence intervals = 0.12-0.30, n = 2,190). Sedentary behavior interventions (n = 2) were not effective. At postintervention, physical activity intervention effectiveness was associated with the BCTs "Biofeedback," "Demonstration of the behavior," "Behavior practice/rehearsal," and "Graded tasks." At follow-up, effectiveness was associated with using "Action planning," "Instruction on how to perform the behavior," "Prompts/cues," "Behavior practice/rehearsal," "Graded tasks," and "Self-reward." Fidelity was only documented in one study. Good evidence was found for behavior change maintenance effects in healthy inactive adults, and underlying BCTs. This review provides translational evidence to improve research, intervention design, and service delivery in physical activity interventions, while highlighting the lack of fidelity measurement.Peer reviewe