There is evidence indicating that an individual can learn a motor skill by observing a model practising it. In the present study we wanted to determine whether observation would permit one to learn the relative timing pattern required to perform a new motor skill. Also, we wanted to determine the joint effects of observation and of physical practice on the learning of that relative timing pattern. Finally, we were interested in finding whether there was an optimal type of model, advanced or beginner, which would lead better to observational learning. Data from two experiments indicated that observation of either a beginner or an advanced model resulted in modest learning of a constrained relative timing pattern. Observation also resulted in significant parameterization learning. However, a combination of observation followed by physical practice resulted in significant learning of the constrained relative timing pattern. These results suggest that observation engages one in cognitive processes similar to those occurring during physical practice.

The aim was to determine in what extent physical activity influences postural control when visual, vestibular, and/or proprioceptive systems are disrupted. Two groups of healthy older women: an active group (74.0 ± 3.8 years) who practiced physical activities and a sedentary group (74.7 ± 6.3 years) who did not, underwent 12 postural conditions consisted in altering information emanating from sensory systems by means of sensory manipulations (i.e., eyes closed, cervical collar, tendon vibration, electromyostimulation, galvanic vestibular stimulation, foam surface). The center of foot pressure velocity was recorded on a force platform. Results indicate that the sensory manipulations altered postural control. The sedentary group was more disturbed than the active group by the use of tendon vibration. There was no clear difference between the two groups in the other conditions. This study suggests that the practice of physical activities is beneficial as a means of limiting the effects of tendon vibration on postural control through a better use of the not manipulated sensory systems and/or a more efficient reweighting to proprioceptive information from regions unaffected by the tendon vibration.

The aim of this study was to analyze the effect of epoch length on intensity classification during continuous and intermittent activities. Methods Ten active students exercised under controlled conditions on a treadmill for four 5-min bouts by combining two effort intensities (running and walking) and two physical activity (PA) patterns (continuous or intermittent). The testing session was designed to generate a known level of moderate to vigorous PA (MVPA) for each condition. These PA levels were used as criterion measures to compare with the accelerometer measures. Data obtained from the accelerometer were reintegrated into 1-sec, 10-sec, 30-sec and 60-sec epochs. Equivalence testing was used to examine measurement agreements between MVPA values obtained with the different epochs and the reference values. Mean absolute percent errors (MAPE) were also calculated to provide an indicator of overall measurement error. Results During the intermittent conditions, only the value obtained with the 1-sec epoch was significantly equivalent to the reference value. With longer epochs the difference increased for both intermittent conditions but in an opposite way: with longer epochs, MVPA decreased during walking but increased during running. Regarding the measurement accuracy, the pattern of variations according to the epoch length selected during the intermittent conditions was identical between walking and running: MAPE increased with the increase in epoch length. MAPE remained low only for the 1-sec epoch (7.6% and 2.7% for walking and running, respectively), increased at 31.3% and 34% for the 10-sec epoch and until near 100% with the 30-and 60-sec epoch lengths.

Background: There is an alarming and constant worldwide progression of physical inactivity and sedentary behaviors in children and adolescents. The present paper summarizes findings from France’s 2020 Report Card on physical activity for children and youth, comparing its results to its 2 previous editions (2016 and 2018). Methods: France’s 2020 Report Card follows the standardized methodology established by the Active Healthy Kids Global Matrix, grading 10 common physical activity indicators using the best available evidence. The grades were informed by national surveys, peer-reviewed literature, government and nongovernment reports, and online information. Results: The expert panel awarded the following grades: Overall Physical Activity: D; Organized Sport Participation and Physical Activity: C−; Active Play: INC; Active Transportation: C−; Sedentary Behaviors: D−; Family and Peers: D−; Physical Fitness: D; School: B−; Community and the Built Environment: F; Government: C. Conclusions: This 2020 edition of France’s Report Card again highlights the alarming levels of physical activity and sedentary behaviors among French children and adolescents, calling for the development of effective national action. It also draws attention to the particular deleterious effects of the COVID-19 confinement on youth’s movement behaviors, which significantly worsened the situation.

The goal of the present study was to determine for children and adults whether practice of a manual aiming task performed on a vertical computer display by moving a mouse facilitates performance of the same task but with a different display orientation. Children (6, 7-8, and 9-10 year olds) and adults practiced a video aiming task using a vertical display. Prior to and after this practice phase, they performed the same task but this time using a horizontal display simulating aiming performance in a normal environment. For all age groups, the results indicated that, on the amplitude component of the task, what has been learned with a vertical display transferred positively to performance of the same task with a horizontal display. No transfer, either positive or negative, was noted on the direction component of the task. A kinematic analysis of the participants' aiming movements revealed that the positive transfer noted on the amplitude component of the task resulted from positive transfer occurring for both the response planning and the motor control processes. Also differences in aiming performance noted between the children and the adults were caused by both more efficient movement planning and online control processes. Finally, the kinematic analysis revealed that both children and adults were able to modulate online their initial movement impulse, providing evidence of continuous or pseudo-continuous movement control based on visual afferent information.