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Dressage is one of the Olympic equestrian sports practiced in several countries using different horse breeds. Specific characteristics of the walk, trot and canter are required for dressage. It has been assumed that some of these traits could be selected for genetically and contribute to dressage performance. The purpose of this study was to compare the walk, trot and conformation characteristics in young horses of different breeds used for dressage. A total of 142 horses age 3 years were classified into 3 groups of breeds (German, French and Spanish saddle horses) and tested using the same procedure. The skeletal conformation measurements were made by image analysis. Gait variables of the walk and trot were measured by the accelerometric gait analysis system Equimetrix. Discriminant analysis could explain the variability between the groups by taking into account the walk (P<0.0003), trot (P<0.0001) and conformation variables (P<0.0001). Many gait and conformation variables were significantly different between the breeds. In summary, the German horses had gait characteristics more adapted for dressage competition, and the results of this group could be used as a reference for early evaluation in dressage. Purebred Spanish horses could be considered as a reference for collected gaits used for farm work and old academic dressage. The gait and conformation tests could be applied in a breeding or crossing plan to detect more accurately young horses with good dressage ability.

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Maintaining equilibrium while riding a horse is a challenging task that involves complex sensorimotor processes. We evaluated the relative contribution of visual information (static or dynamic) to horseback riders' postural stability (measured from the variability of segment position in space) and the coordination modes they adopted to regulate balance according to their level of expertise. Riders' perceptual typologies and their possible relation to postural stability were also assessed. Our main assumption was that the contribution of visual information to postural control would be reduced among expert riders in favor of vestibular and somesthetic reliance. Twelve Professional riders and 13 Club riders rode an equestrian simulator at a gallop under four visual conditions: (1) with the projection of a simulated scene reproducing what a rider sees in the real context of a ride in an outdoor arena, (2) under stroboscopic illumination, preventing access to dynamic visual cues, (3) in normal lighting but without the projected scene (i.e., without the visual consequences of displacement) and (4) with no visual cues. The variability of the position of the head, upper trunk and lower trunk was measured along the anteroposterior (AP), mediolateral (ML), and vertical (V) axes. We computed discrete relative phase to assess the coordination between pairs of segments in the anteroposterior axis. Visual field dependence-independence was evaluated using the Rod and Frame Test (RFT). The results showed that the Professional riders exhibited greater overall postural stability than the Club riders, revealed mainly in the AP axis. In particular, head variability was lower in the Professional riders than in the Club riders in visually altered conditions, suggesting a greater ability to use vestibular and somesthetic information according to task constraints with expertise. In accordance with this result, RFT perceptual scores revealed that the Professional riders were less dependent on the visual field than were the Club riders. Finally, the Professional riders exhibited specific coordination modes that, unlike the Club riders, departed from pure in-phase and anti-phase patterns and depended on visual conditions. The present findings provide evidence of major differences in the sensorimotor processes contributing to postural control with expertise in horseback riding.

The aims of this study were 1) to assess the ergonomic physical risk factors from practitioner’s viewpoint in a truck assembly plant with an in-house observational method and the NIOSH lifting equation, and 2) to compare the results of both methods and their differences. The in-house ergonomic observational method for truck assembly i.e. the SCANIA Ergonomics Standard (SES) and the NIOSH lifting equation were applied to evaluate physical risk factors and lifting of loads by operators. Both risk assessment approaches revealed various levels of risk, ranging from low to high. Two workstations were identified by the SES method as high risk. The NIOSH lifting index (LI) was greater than two for four lifting tasks. The results of the SES method disagreed with the NIOSH lifting equation for lifting tasks. Moreover, meaningful variations in ergonomic risk patterns were found for various truck models at each workstation. These results provide a better understanding of the physical ergonomic exposure from practitioner’s point of view in the automotive assembly plant.

SummaryThe purpose of this study was to describe the relationship between the scores of dressage horses in competition and gait characteristics. During twenty five dressage tests, eighteen horses were tested with a gait analysis system. According to the level of the dressage test, two groups of horses were used : a group of ten young horses (4, 5 and 6 year old) and a group of eight experienced horses (7, 8, 9, 11 and 13 year old). An accelerometric device fixed at the sternum measured the dorsoventral and longitudinal accelerations. Stride frequency, symmetry, regularity, dorsoventral displacement, longitudinal activity, dorsoventral activity, vector of propulsion and vector of braking were calculated from horse accelerations for each figure of dressage test. At the same time, the judges marked all the figures. Judges' sheets were collected to calculate correlations between marks, total score, and gait variables measured during the test. The results showed that specific characteristics of the walk and trot were required in young horses. The trot should be slow with a large dorsoventral displacement and a large longitudinal activity. The walk should be slow, regular, symmetric, with a large dorsoventral activity and dorsoventral displacement. A good movement performed at the canter was indicated by high longitudinal and dorsoventral activities. Few correlations for the group of experienced horses were observed.Keywords: kinetics; dressage; judge; marks; test Korrelation zwischen kinetischen Gangcharakteristika und der Benotung von DressuraufgabenZiel der Arbeit war die Untersuchung von Korrelationen zwischen der sportrichterlichen Benotung von Dressuraufgaben im Wettkampf und den entsprechenden Gangcharakteristika. Während fünfundzwanzig Dressuraufgaben wurden achtzehn junge Pferde mit einem Ganganalysesystem untersucht. Diese Pferde wurden je nach Wettkampf in zwei Gruppen eingeteilt: 4, 5 und 6 jährige Pferde sowie ältere, erfahrene Pferde. Ein im Bereich des Brustbeins fixierter Beschleunigungsmesser maß die dorsoventralen und longitudinalen Beschleunigungen. Schrittfrequenz , Symmetrie, Regelmäßigkeit, dorsoventrale Bewegung, longitudinale und dorsoventrale Aktivität, Beschleunigung und Verzögerung wurden für jede Dressuraufgabe berechnet.Gleichzeitig bewerteten die Dressurrichter die Aufgaben. Die Benotungen wurden gesammelt, um die Zusammenhänge zwischen der Bewertung der Dressuraufgaben und der Gangart, dem Gesamtergebnis und den kinetisch gemessenen Gangkomponenten zu berechnen. Die Ergebnisse zeigen, dass bei jungen Pferden spezifischen Merkmale von Schritt und Trab gefordert werden. Der Trab sollte langsam sein mit ausgeprägter dorsoventraler Bewegung und deutlicher longitudinaler Aktivität. Der Schritt sollte langsam, regelmäßig und symmetrisch sein, mit deutlicher dorsoventraler Bewegung und Aktivität. Der Galopp war durch ausgeprägte longitudinale und dorsoventrale Aktivitäten charakterisiert. Für die Gruppe der erfahrenen Pferde wurden allerdings nur wenige Zusammenhänge beobachtet.

SummaryThe equestrian literature and reports of experienced riders indicated that attitude of a horse's head and neck is related to the equine locomotion characteristics. The purpose of this study was to quantify the effects of 3 types of reins on locomotion at walk and trot. Eight saddle horses were tested in an automatic walker without reins, with rubber bands, Chambons and Back lift 1 , using the same procedure. The rubber bands closed the head-neck angle, whereas the Chambons and the Back lift opened it. The gait characteristics were measured with the Equimetrix 2 gait analysis system. Two accelerometric devices were fixed on the sternum and sacrum to measure the kinetic characteristics of the fore-and hindlimbs at walk and trot. Analysis of variance was used to test the effects of reins on the fore-and hindlimbs. All 3 types of reins significantly (P<0.05) modified walk and trot, with increased forelimb propulsion at the trot (P<0.05). Chambons increased the dorsoventral activity of the hindlimbs at the trot and hindlimb propulsion at the walk (P<0.05). Back lift increased forelimb dorsoventral activity both at the trot and walk (P<0.05). It was concluded that the Chambons increased the activity of the hindlimbs while Back lift increased that of the forelimbs.The use of reins modified the head placement and the foreand hindlimbs activity. The specific effect of each type of rein can be used for training, rehabilitation or management of locomotor's injury.

This study compared the results of three risk assessment tools (self-reported questionnaire, observational tool, direct measurement method) for the upper limbs and back in a truck assembly plant at two cycle times (11 and 8 min). The weighted Kappa factor showed fair agreement between the observational and direct measurement method for the arm (0.39) and back (0.47). The weighted Kappa factor for these methods was poor for the neck (0) and wrist (0) but the observed proportional agreement (P) was 0.78 for the neck and 0.83 for the wrist. The weighted Kappa factor between questionnaire and direct measurement showed poor or slight agreement (0) for different body segments in both cycle times. The results revealed moderate agreement between the observational tool and the direct measurement method, and poor agreement between the self-reported questionnaire and direct measurement. Practitioner Summary: This study provides risk exposure measurement by different common ergonomic methods in the field. The results help to develop valid measurements and improve exposure evaluation. Hence, the ergonomist/practitioners should apply the methods with caution, or at least knowing what the issues/errors are.