Effects of Time of Day and Sleep Deprivation on Motorcycle-Driving Performance

The aim of this study was to investigate whether motorcycle handling capabilities – measured by means of the efficiency of emergency manoeuvres – were dependent on prior sleep deprivation and time of day. Twelve male participants voluntarily took part in four test sessions, starting at 6 a.m., 10 a.m., 2 p.m., and 6 p.m., following a night either with or without sleep. Each test session comprised temperature and sleepiness measurements, before three different types of motorcycling tests were initiated: (1) stability in straight ahead riding at low speed (in “slow motion” mode and in “brakes and clutch” mode), (2) emergency braking and (3) crash avoidance tasks performed at 20 kph and 40 kph. The results indicate that motorcycle control at low speed depends on time of day, with an improvement in performance throughout the day. Emergency braking performance is affected at both speeds by time of day, with poorer performance (longer total stopping distance, reaction time and braking distance) in the morning, and also by sleep deprivation, from measurements obtained at 40 kph (incorrect initial speed). Except for a tendency observed after the sleepless night to deviate from the initial speed, it seems that crash avoidance capabilities are quite unaffected by the two disturbance factors. Consequently, some motorcycle handling capabilities (stability at low speed and emergency braking) change in the same way as the diurnal fluctuation observed in body temperature and sleepiness, whereas for others (crash avoidance) the participants were able to maintain their initial performance level despite the high levels of sleepiness recorded after a sleepless night. Motorcycle riders have to be aware that their handling capabilities are limited in the early morning and/or after sleep deprivation. Both these situations can increase the risk of falls and of being involved in a road accident

Progresser à velo : cyclisme au cycle 3

Fiche : séance d'un module d'apprentissage du vélo à l'école primaire

Cyclisme : les fondamentaux de l'apprentissage

Pratique scolaire du cyclisme : développement des compétences relatives à 6 fondamentaux : propulsion, équilibration, direction, maitrise de la bicyclette, gestion de l'effort, prise d'informations et anticipation

Rythmicité circadienne de la fréquence de pédalage spontanée, de la cinématique du mouvement et des variables cardio-respiratoires au cours d'exercices de type aérobie

CAEN-BU Sciences et STAPS (141182103) / SudocSudocFranceF

Faire avec et pour les acteurs de terrain : enjeux méthodologiques des théories de l'activité pour agir sur la temporalité longue d'une démarche ethnographique

International audienc

Faire de la recherche fondamentale de terrain dans les établissements scolaires : orientations épistémologiques et implications méthodologiques

International audienceDans le présent article, l’objectif est de décrire la recherche fondamentale de terrain (Clot, 2008a, 2008b ; Wisner, 1995) telle que nous la concevons dans nos programmes de recherche et telle que nous la mettons en œuvre, dans les établissements scolaires avec les professionnels de l’enseignement. Sont présentés les orientations épistémologiques et théoriques ainsi que les choix méthodologiques que nos études à visées transformative et épistémique adoptent pour mener une recherche fondamentale de terrain. Dans ce contexte, l’article développe la problématique des relations chercheur(s) et professionnel(s) en décrivant les processus de co-construction de l’objet d’étude et d’élaboration collective des transformations de l’activité que la méthode d’entretien d’autoconfrontation permet de faire émerger au cours de la recherche. Trois études illustrent cette démarche de recherche fondamentale de terrain menée avec des enseignants en milieu scolaire. Une mise en discussion de ces trois études à propos des conditions du développement de l’activité des enseignants permet de souligner des points d’accord et de débat avec d’autres travaux qui se réclament d’une recherche fondamentale de terrain

The effects of sleep deprivation and time of day on cognitive performance

The extent to which the diurnal fluctuations of different cognitive processes could be affected by sleep loss may be explored to predict performance decrements observed in the real world. Twenty healthy male subjects voluntarily took part in 8 test sessions at 06:00, 10:00, 14:00, and 18:00 h, following either a night with or without sleep in random order. Measurements included oral temperature, simple reaction time, sign cancelation, Go/NoGo, and the Purdue pegboard test. The results indicate that simple reaction time and motor coordination had morning-afternoon variations closely following the rhythms of temperature and vigilance. Inhibitory attention (Go/NoGo) presented no morning-afternoon variations. Sleep deprivation may affect the profiles of cognitive performance depending on the processes solicited. Sustained and inhibitory attention are particularly affected in the morning (after 24 and 28 waking hours), while a complex task (visuo-motor coordination) would be affected after 32 waking hours only

A developmental research-based teacher education: designing and implementing a new program for preservice teachers in France

International audienceIn many countries, preservice teachers’ (PTs) education programs neglect the importance of connecting research and practice. Reconciling training and research remains problematic for PTs, who often encounter difficulties in making connections between the academic knowledge acquired in university and their experiences in the classroom. This context inhibits the development of their professional skills. Taking this observation as our starting point, the aim of this article is to conceptualize and to illustrate an alternative approach in order to establish a reciprocal link between training and research, sketching the outlines of a developmental research-based program of teacher education. We begin by studying different training-based approaches to research and their respective limitations, identifying the key principles and steps of a developmental research-based approach to teacher education. Then, we illustrate these principles using data from empirical studies. Finally, we discuss the conditions required for the implementation of such an approach to the teacher education of PTs in France

Activité physique à domicile pour les seniors : revue de la question et proposition d’une pratique optimisée

International audiencePhysiological and functional alterations caused by aging can lead to a loss of autonomy for daily living activities. In order to prevent these deleterious effects, it is recommended to practice physical activity regularly. Because exercise is not always accessible to older adults, this review reports the state of the art in home-based training research. It appeared that without supervision, physical training effects are lower or even non-existent compared to traditional exercise. It is also associated with high drop-out rates Semi-supervised home-based training could lead to higher health benefits but these benefits remain lower than supervised exercises. Remote contribution by a professional through a videoconferencing system could be an interesting solution that would lower the price and allow better accessibility to exercise training in the aging population. In the second part of this article, we present an optimized solution answering the problems identified in this review. The implementation of this innovating system is promising because of the high adherence, compliance and a level of satisfaction of the participants.Les altérations physiologiques et fonctionnelles liées au vieillissement peuvent avoir un impact sur l’autonomie des personnes dans les activités de la vie quotidienne. Afin de prévenir et de limiter ces effets délétères, il est recommandé d’avoir une activité physique adaptée régulière. Cependant, l’accès à un entraînement efficace n’est pas toujours possible pour les seniors. Dans une première partie, nous examinons donc l’état des connaissances scientifiques sur les différentes modalités d’entraînement au domicile d’un public âgé. En l’absence de supervision, il apparaît que les bénéfices associés à la pratique sont moindres et que l’adhésion au programme est réduite. Dans le cadre d’entraînements à domicile semi-supervisés, il semble que les bénéfices sur la santé soient encore une fois faibles. Lors d’entraînements à domicile avec supervision à distance, l’adhésion et les effets sur la santé semblent cette fois plus importants. Ainsi, afin de répondre aux problématiques relevées par cette revue, dans la seconde partie de ce travail nous présentons un projet novateur d’accompagnement à distance par un professionnel au moyen d’un système de visioconférence collectif. La mise en place de ce projet est prometteuse puisque les résultats préliminaires montrent des taux d’adhésion, d’observance et un niveau de satisfaction très élevés

Effects of Waking Time and Breakfast Intake Prior to Evaluation of Psychomotor Performance in the Early Morning

Many studies conducted in the field of chronobiology report diurnal fluctuation incognitive and physical performance that occurs in phase with the body temperaturecircadian rhythm. Waking time and whether or not breakfast is consumed arecurrently considered to influence the diurnal fluctuation in data collected in themorning at 06:00 h and evening at 18:00 h. Nineteen male subjects participated infour test sessions to examine if wake-up time (04:00 h or 05:00 h) and eating or not eating breakfast influence psychomotor performance capacity at 06:00 h. All four sessions were separated by 36 h and were completed in a counterbalanced order. Each test session comprised sign cancellation, Epworth Sleepiness Scale, simple reaction time, and manual dexterity tests. Most of the results indicate that psychomotor performance when evaluated at 06:00 h under each of the four different study situations (two waking times and two breakfast conditions) is not statistically significantly different. Consequently, previous results that documented diurnal fluctuations in morning and evening performance capacities, with test sessions at 06:00 h, are confirmed. Being less efficient in the early morning than in the afternoon potentially exposes people to elevated risk of accident and injury at this time of the day. Prior waking time and/or consumption of a light meal, plus other countermeasures mentioned in the literature, are insufficient to prevent this risk