Spontaneous change from seated to standing cycling position with increasing power is associated with a minimization of cost functions     

Antony Costes  Nicolas A Turpin  David Villeger  Pierre Moretto  Bruno Watier 《Journal of sports sciences》2018,36(8):907-913

Spontaneous changes of movement patterns may allow to elucidate which criteria influence movement pattern preferences. However, the factors explaining the sit-stand transition in cycling are unclear. This study investigated if biomechanical and/or muscle activation cost functions could predict the power at which the spontaneous sit-stand transition occurs. Twenty-five participants performed an incremental test leading to the sit-to-stand transition, and subsequent randomized pedaling trials at 20 to 120% of the transition power in seated and standing position. A Moment Cost Function based on lower limbs net joint moments and two Electromyographic Cost Functions based on EMG data were defined. All cost functions increased with increasing crank power (p < 0.001) but at different rates in the seated and standing positions. They had lower values in the seated position below the transition power and lower values in the standing position above the transition power (p < 0.05). These results suggest that spontaneous change of position observed in cycling with increasing crank power represents an optimal choice to minimize muscular efforts. These results support the use of simple cost functions to define optimal settings in cycling and to assess the cost of cycling during short-term efforts.  相似文献   

Spatiotemporal analysis of 3D kinematic asymmetry in professional cycling during an incremental test to exhaustion     

Camille Pouliquen  Guillaume Nicolas  Benoit Bideau  Gérard Garo  Armand Megret  Paul Delamarche 《Journal of sports sciences》2018,36(19):2155-2163

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Reviews     

Jason Owen-Smith  John Gascoigne  Alan Chalmers  Audra J. Wolfe  Ivan Crozier  Jan Crosthwaite  Jonathan Simon  Peter Anstey  William Clower  Mark Parascandola  Robert L. Campbell  Charlotte Bigg  R. J. Hankinson  Nicolas Rasmussen  Christer Nordlund  Nessy Allen  Craig Sean McConnell  David Oldroyd  Edward Wisniewski  Jessie Saul  Stephanie H. Kenen  Ina Roy  Bradley Monton  Dianah Leigh Jackson 《Metascience》2001,10(2):232-319

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Fine Motor Control Underlies the Association Between Response Inhibition and Drawing Skill in Early Development     

Andrew Simpson  Reshaa Al Ruwaili  Richard Jolley  Hayley Leonard  Nicolas Geeraert  Kevin J. Riggs 《Child development》2019,90(3):911-923

Previous research shows that the development of response inhibition and drawing skill are linked. The current research investigated whether this association reflects a more fundamental link between response inhibition and motor control. In Experiment 1, 3- and 4-year-olds (n = 100) were tested on measures of inhibition, fine motor control, and drawing skill. Data revealed an association between inhibition and fine motor control, which was responsible for most of the association observed with drawing skill. Experiment 2 (n = 100) provided evidence that, unlike fine motor control, gross motor control and inhibition were not associated (after controlling for IQ). Alternative explanations for the link between inhibition and fine motor control are outlined, including a consideration of how these cognitive processes may interact during development.  相似文献   

The promise and peril of the state in neoliberal times: implications for the critical environmental education movement in Brazil     

Nicolas Stahelin  Inny Accioly  Celso Sánchez 《Environmental Education Research》2015,21(3):433-446

Neoliberal ideology has made an impact on environmental education (EE) policies and practices in Brazil. The EE in Family Agriculture Program, of national scope and administered by the Ministry of the Environment, seeks to promote sustainable development in rural areas, specifically through strategies focused on adult education and non-formal education aimed at small producers (family agriculture). This program reveals profound ideological contradictions between the critical and transformative rhetoric of public policy and the actual program structures and practices administered by the state in a dependent economy, which primarily serve to reinforce a capitalist mode of production marked by high environmental impact and deeply stratified class relations. In the neoliberal era, states intending to protect the environment through critical EE strategies suffer serious limitations due to their role as stewards of a globalized economy based on the supply of raw materials, high-impact land-use, and a cheap labor force.  相似文献   

Does research organization influence academic production?: Laboratory level evidence from a large European university     

Nicolas Carayol  Mireille Matt 《Research Policy》2004,33(8):1081-1102

The paper analyses scientific research production at the laboratory level. The evidence on which the study is based describes precisely the research activity over the period 1993-2000 of more than eighty labs belonging to Louis Pasteur University, a large and well-ranked European research university. The research organization of the labs is analysed by focusing on the characteristics of the research personnel in relation with the scores in two outcomes that are publications and patents. The paper proposes a five-classes typology of laboratories that highlights different styles of research organization and productivity at the laboratory level. It also studies the determinants of the publication performances of labs. We show how appropriate combinations of inputs in academic labs may be strongly associated to high publication performances. We find that combining full-time researchers and university professors in labs tend to preserve incentives. Highly publishing labs also patent. The size of the labs, the individual promotions, and the role of non-permanent researchers and of non-researchers are also underlined.  相似文献   

The advantage of distributed practice in a blended learning setting     

Jost  Nathanael S.  Jossen  Sina L.  Rothen  Nicolas  Martarelli  Corinna S. 《Education and Information Technologies》2021,26(3):3097-3113

Education and Information Technologies - Ongoing digital transformations facilitate the conduct of online courses and distance learning. In this study, it was aimed to investigate the role of...  相似文献   

Aging and tennis playing in a coincidence-timing task with an accelerating object: the role of visuomotor delay     

Lobjois R  Benguigui N  Bertsch J 《Research quarterly for exercise and sport》2005,76(4):398-406

The purpose of the present study was to determine whether playing a specific ball sport, such as tennis, could maintain the coincidence-timing (CT) performance of older adults at a similar level to that of younger ones. To address this question, tennis players and nonplayers of three different age ranges (ages 20-30, 60-70, and 70-80 years) performed a simple CT task consisting of timing their response (pressing a button) to coincide with the arrival of a stimulus at a target. The stimulus moved at either an accelerating, constant, or decelerating velocity. As expected, all participants were affected by the velocity manipulation, which led to late and early responses to accelerating and decelerating stimuli, respectively. Whereas this response bias was increasingly pronounced with advancing age in nonplayers, no difference was found among player groups of different ages. Finally, we showed that the length of the visuomotor delay could explain the effect of nonconstant velocities.  相似文献   

The complex route to success: complex problem-solving skills in the prediction of university success     

Matthias J. Stadler  Nicolas Becker  Samuel Greiff  Frank M. Spinath 《高等教育研究与发展》2016,35(2):365-379

Successful completion of a university degree is a complex matter. Based on considerations regarding the demands of acquiring a university degree, the aim of this paper was to investigate the utility of complex problem-solving (CPS) skills in the prediction of objective and subjective university success (SUS). The key finding of this study was that CPS was not only strongly correlated to objective university success but also explained university grade point averages (GPA) of N?=?78 German business students even after intelligence and high-school GPA were controlled for. In addition, priority setting while working on a complex problem explained self-rated SUS. Given this incremental validity over the most established predictors of objective university success and its versatility, we argue that CPS may be a valuable addition to existing predictors in university applicant selection.  相似文献   

Increased exhaled breath condensate 8-isoprostane after a swimming session in competitive swimmers     

Mathieu C. Morissette  Nicolas Murray  Julie Turmel  Julie Milot  Louis-Philippe Boulet 《European Journal of Sport Science》2016,16(5):569-576

Objectives: This study aimed to evaluate the levels of 8-isoprostane (8-IsoP) in the airways of competitive swimmers at baseline and after a swimming session according to their airway responsiveness. Methods: Twenty-three swimmers and six lifeguards had a baseline spirometry and bronchoprovocative challenges. During a second visit, swimmers performed a usual swimming session while lifeguards stayed in the same pool environment for the same time period. Forced expiratory volume in one second (FEV₁) was measured before and 5 min after the end of the session. Exhaled breath condensate (EBC) was sampled before and 10 min after the session and EBC 8-IsoP levels were analysed by enzyme immunoassay. Change in EBC 8-IsoP from baseline to post-swimming session was calculated. Results: We observed no relationships between airway hyper-responsiveness and 8-IsoP values before or after swimming in swimmers. The levels of 8-IsoP were significantly higher after the training session (mean value 2.9, s?=?0.5 pg?mL^?1) than at baseline (mean value 1.9, s?=?0.4 pg?mL^?1) in swimmers only (p?=?.012). EBC 8-IsoP levels after the swimming session significantly correlated with the percent change in FEV₁ after swimming. Conclusions: EBC 8-IsoP levels were increased after training in swimmers but not in lifeguards, suggesting that exercise-induced hyperpnoea in a chlorinated pool environment increases airways oxidative stress.  相似文献