BackgroundWe are developing since 2010 with Thales and the Fédération Française de Rugby (FFR) M-Rex, a new kind of rugby scrum simulator. The study questioned whether it could improve safety and protect players from injury by using it as a tool for training/coaching the packs.AimTo explore the anticipatory postural adjustments (APAs) during the engagement of the ruck, because these predictive neck and back muscles contractions protect the spinal cord at the time of impacts, which is crucial to prevent injuries.MethodsWe quantified the kinematics and the EMG activities in high-level front row players during their initial engagement, when scrummaging with M-Rex. All studies were performed with one player interacting with the robot, at first, and then with the three players acting together.ResultsFor most of the tested high-level players, the APA latencies were highly variable from trial to trial even though the engagement resulted in similar impacts. At time, the onset of the electromyography activity in the neck and back muscles showed latencies inferior to 50 ms or even close to zero prior to the impact, which rendered muscle contractions inefficient as APAs. We were also unable to identify clear muscular synergies underlying the APAs because of their great variability on a trial-to-trial basis. Finally, the APAs were not related to the amplitude of the ensuing impact and were asymmetric in most trials. All these characteristics held true, whether the player was playing alone or with two other frontline players.ConclusionOur result suggest that APAs should be systematically tested in high-level rugby players as well as in any high-level sport men at risk of neck and back injuries. Because APAs can be efficiently trained, our study paves the way to design individual position-specific injury prevention programme.

AimUsing M-Rex, a rugby scrum simulator, we developed tools to describe scrummaging forces and to prevent accident.MethodsWe tested three groups of frontliners at national level. The simulator was passive or responded to the player(s) to simulate the reaction of opposite players. Sensors in the beam measured the force exerted by each of the players. Their movements were recorded with a Codamotion system.ResultsThe force signals exhibited two phases: a transient phase, similar to a damped sinusoid with a dominant frequency around 5 Hz when the players scrummaged alone and with a wider range when playing together; then, a sustained phase could be decomposed in two components: a DC component remained stable whether frontliners played alone or together. In contrast, its variability decreased when the frontliners played together compared with when they played alone. As for the oscillations, the frontliners exhibited a large variability in their ability to synchronise their efforts during the sustained phase. The synchronisation between the hooker and the props was quite efficient, while it was always missing between two props. Finally, we were able to study postural readjustments and their synchronisation among players during the sustained phase.ConclusionThis study shows that by using adequate methods, it is possible to assess the frontline collective intelligence. These findings may pave the way for innovative methods of training to improve players’ collective behaviour.

Climate change is becoming one of the biggest environmental challenges in the 21st century. New-energy vehicle produce less greenhouse gases as compared to the traditional vehicles with internal combustion engines. New energy vehicles have great potential to successfully address the issue of climate change. Additionally, new energy materials can also be used in automotive lightweight technology. This paper discussed the currently lightweight materials including high-strength low-alloy steel (HSLA), carbon fiber composite material, and modified plastics. According to the discussion in this paper, high-strength low-alloy steel can be used in automotive safety parts, chassis, and body. Carbon fiber composite materials can be used in car bodies, chassis, roofs, doors, head covers, hoods, rear wings, center consoles, trim strips, drive shafts, leaf springs, frames, brake pads, interior and exterior accessories. Modified plastics can be mainly used in exterior decorative parts, interior decorative parts, functional parts, and structural parts. However, three are still many drawbacks of application of new energy materials in new-energy vehicle. The current new energy materials used in automotive lightweight technology are usually costly and time-consuming. Moreover, the characteristics of the new energy materials are still not clear. It could have a negative impact on the environment. Before this technology can be widely used in new-energy vehicles, more research is needed regarding the new energy materials.