共查询到20条相似文献，搜索用时 15 毫秒
1.
M. Rhodin C. B. Gómez Álvarez A. Byström C. Johnston P. R. Van Weeren L. Roepstorff M. A. Weishaupt 《Equine veterinary journal》2009,41(3):274-279
Reasons for performing study: Dressage involves training of the horse with the head and neck placed in a position defined by the rider. The best position for dressage training is currently under debate among riders and trainers, but there are few scientific data available to confirm or disprove the different views. Objective: To evaluate the kinematic effects of different head and neck positions (HNPs) in elite dressage horses ridden at trot. Methods: Seven high‐level dressage horses were subjected to kinetic and kinematic measurements when ridden on a treadmill with the head and neck in 5 different positions. Results: Compared to free trot on loose reins the HNP desired for collected trot at dressage competitions increased T6 vertical excursion, increased sacral flexion and decreased limb retraction after lift‐off. Further increasing head or head and neck flexion caused few additional changes while an extremely elevated neck position increased hindlimb flexion and lumbar back extension during stance, increased hindlimb flexion during swing and further increased trunk vertical excursion. Conclusions: The movements of the horse are significantly different when ridden on loose reins compared to the position used in collected trot. The exact degree of neck flexion is, however, not consistently correlated to the movements of the horse's limbs and trunk at collected trot. An extremely elevated neck position can produce some effects commonly associated with increased degree of collection, but the increased back extension observed with this position may place the horse at risk of injury if ridden in this position for a prolonged period. Potential relevance: Head and neck positions influence significantly the kinematics of the ridden horse. It is important for riders and trainers to be aware of these effects in dressage training. 相似文献
2.
P. de COCQ H. PRINSEN N. C. N. SPRINGER P. R. van WEEREN M. SCHREUDER M. MULLER J. L. van LEEUWEN 《Equine veterinary journal》2009,41(5):423-427
Reason for performing study: During trot, the rider can either rise from the saddle during every stride or remain seated. Rising trot is used frequently because it is widely assumed that it decreases the loading of the equine back. This has, however, not been demonstrated in an objective study. Objective: To determine the effects of rising and sitting trot on the movements of the horse. Hypothesis: Sitting trot has more extending effect on the horse's back than rising trot and also results in a higher head and neck position. Methods: Twelve horses and one rider were used. Kinematic data were captured at trot during over ground locomotion under 3 conditions: unloaded, rising trot and sitting trot. Back movements were calculated using a previously described method with a correction for trunk position. Head‐neck position was expressed as extension and flexion of C1, C3 and C6, and vertical displacement of C1 and the bit. Results: Sitting trot had an overall extending effect on the back of horses when compared to the unloaded situation. In rising trot: the maximal flexion of the back was similar to the unloaded situation, while the maximal extension was similar to sitting trot; lateral bending of the back was larger than during the unloaded situation and sitting trot; and the horses held their heads lower than in the other conditions. The angle of C6 was more flexed in rising than in sitting trot. Conclusions and clinical relevance: The back movement during rising trot showed characteristics of both sitting trot and the unloaded condition. As the same maximal extension of the back is reached during rising and sitting trot, there is no reason to believe that rising trot was less challenging for the back. 相似文献
3.
The objective was to evaluate the effects of gymnastic training on stride characteristics of walk and trot in therapy horses carrying riders of different weights. Eighteen horses used for therapeutic riding 5 days/week were randomly divided into 2 groups. Nine horses performed gymnastic (GYM) exercises after therapeutic riding on 4 days/week for 3 months, 9 horses did no additional exercises (SED). On days 0 and 90, an inertial sensor mounted to the girth on the ventral midline was used to evaluate stride characteristics when horses were ridden at walk (1.3 m/second) and trot (3.0 m/second) by able-bodied riders representing rider: horse body weight ratios (BWRs) 15%, 20%, and 25%. On day 0, the measured variables did not differ significantly between sedentary (SED) and GYM groups, but on day 90, the following statistically significant results were found: GYM-trained horses had higher regularity for all BWRs at walk and 15% and 20% BWRs at trot. Higher stride symmetry was found in GYM-trained horses carrying 25% BWRs at walk and all rider weights at trot. Dorsoventral displacement was higher in GYM-trained horses when carrying 20% and 25% BWRs at walk and 25% BWRs at trot. Dorsoventral power was lower in SED-trained versus GYM-trained horses carrying 15% BWR at walk and 20% BWR at trot. A more regular and symmetrical stride with a larger range of dorsoventral trunk motion is likely to provide a better therapeutic riding experience. 相似文献
4.
Gomez Alvarez CB Bobbert MF Lamers L Johnston C Back W van Weeren PR 《Equine veterinary journal》2008,40(2):147-152
REASON FOR PERFORMING STUDY: There are no detailed studies describing a relationship between hindlimb lameness and altered motion of the back. OBJECTIVES: To quantify the effect of induced subtle hindlimb lameness on thoracolumbar kinematics in the horse. METHODS: Kinematics of 6 riding horses were measured during walk and trot on a treadmill before and during application of pressure on the sole of the left hindlimb using a well-established sole pressure model. Reflective markers were located at anatomical landmarks on the limbs, back, head and neck for kinematic recordings. Ground reaction forces (GRF) in individual limbs were calculated from kinematics to detect changes in loading of the limbs. RESULTS: When pressure on the sole of the hindlimb was present, horses were judged as lame (grade 2 on the AAEP scale 1-5) by an experienced clinician. No significant unloading of this limb was found in the group of horses (unloading was observed in 4 animals, but was not detectable in the other 2), but statistically significant effects on back kinematics were detected. The overall flexion-extension (FE) range of motion (ROM) of the vertebral column was increased at walk, especially in the thoracic segments. Axial rotation (AR) ROM of the pelvis was also increased. At trot, the FE ROM was decreased only in the segment L3-L5-S3. During the stance phase of the lame limb, the segment T6-T10-T13 was more flexed and the neck was lowered at both gaits; the thoracolumbar segments were more extended at walk and trot. There were no significant changes in the stride length or protraction-retraction angles in any of the limbs. CONCLUSIONS: Subtle hindlimb lameness provoked slight but detectable changes in thoracolumbar kinematics. The subtle lameness induced in this study resulted in hyperextension and increased ROM of the thoracolumbar back, but also in decreased ROM of the lumbosacral segment and rotational motion changes of the pelvis. POTENTIAL RELEVANCE: Even subtle lameness can result in changes in back kinematics, which emphasises the intricate link between limb function and thoracolumbar motion. It may be surmised that, when chronically present, subtle lameness induces back dysfunction. 相似文献
5.
Wennerstrand J Johnston C Roethlisberger-Holm K Erichsen C Eksell P Drevemo S 《Equine veterinary journal》2004,36(8):707-711
REASONS FOR PERFORMING STUDY: Earlier studies have developed a clinical tool to evaluate objectively the function of the equine back. The ability to differentiate horses with back pain from asymptomatic, fully functioning horses using kinematic measures from this tool has not been evaluated. OBJECTIVES: To compare the kinematics of the back at walk and trot in riding horses with back dysfunction to the same parameters in asymptomatic sport horses. METHODS: The kinematics of the back in 12 horses with impaired performance and back pain were studied at walk and trot on a treadmill. Data were captured for 10 sees at 240 Hz. Range of movement (ROM) and intravertebral pattern symmetry of movement for flexion and extension (FE), lateral bending (LB) and axial rotation (AR) were derived from angular motion pattern data and the results compared to an earlier established database on asymptomatic riding horses. RESULTS: At walk, horses with back dysfunction had a ROM smaller for dorsoventral FE in the caudal thoracic region (T13 = 7.50 degrees, T17 = 7.71 degrees; P<0.05), greater for LB at T13 (8.13 degrees; P<0.001) and smaller for AR of the pelvis (10.97 degrees; P<0.05) compared to asymptomatic horses (FE-T13 = 8.28 degrees, FE-T17 = 8.49 degrees, LB-T13 = 6.34 degrees, AR-pelvis = 12.77 degrees). At trot, dysfunctional horses had a smaller (P<0.05) ROM for FE at the thoracic lumbar junction (T17 = 2.46 degrees, L1 = 2.60 degrees) compared to asymptomatic horses (FE-T17 = 3.07 degrees, FE-L1 = 3.12 degrees). CONCLUSIONS: The objective measurement technique can detect differences between back kinematics in riding horses with signs of back dysfunction and asymptomatic horses. The clinical manifestation of back pain results in diminished flexion/extension movement at or near the thoracic lumbar junction. However, before applying the method more extensively in practice it is necessary to evaluate it further, including measurements of patients whose diagnoses can be confirmed and long-term follow-ups of back patients after treatment. POTENTIAL RELEVANCE: Since the objective measurement technique can detect small movement differences in back kinematics, it should help to clinically describe and, importantly, objectively detect horses with back pain and dysfunction. 相似文献
6.
A recent epidemiological study indicated that various factors may be related to injury in dressage horses, but the mechanism by which these injuries occur has yet to be determined. The suspensory ligament (SL) is a frequent site of injury, and it is assumed that greatest strain is placed on this structure in collected trot; this has yet to be proved conclusively. The study aimed to investigate the effect of collected and extended trot on the hindlimb movement pattern. Four dressage horses were fitted with markers and inertial motion sensors (IMS). High‐speed video was obtained for 2 strides on each rein in collected and extended trot on 3 different surfaces: waxed outdoor; sand/plastic granules; and waxed indoor. Maximal tarsal flexion during stance and distal metatarsal coronary band ratio (MTCR), representing fetlock extension, were determined. Inertial motion sensor data determined stride duration, speed and stride length. Data were compared between collection and extension within horses on each surface, and compared between surfaces. Collected trot had significantly lower speed and stride length but longer stride duration than extended trot on all surfaces. All horses had less tarsal flexion and fetlock extension in collected compared with extended trot (P<0.05), which is likely to increase SL loading. The study findings indicate that extended trot may increase SL strain, providing a possible explanation for the high incidence of SL injury in horses trained for extravagant movement. It is possible that substantial use of extended trot could be a risk factor for development of suspensory desmitis, which might be one contributory factor in the prevalence of suspensory desmitis in young horses repeatedly undertaking extravagant movement. 相似文献
7.
Gómez Alvarez CB Wennerstrand J Bobbert MF Lamers L Johnston C Back W van Weeren PR 《Equine veterinary journal》2007,39(3):197-201
REASONS FOR PERFORMING STUDY: Lameness has often been suggested to result in altered movement of the back, but there are no detailed studies describing such a relationship in quantitative terms. OBJECTIVES: To quantify the effect of induced subtle forelimb lameness on thoracolumbar kinematics in the horse. METHODS: Kinematics of 6 riding horses was measured at walk and at trot on a treadmill before and after the induction of reversible forelimb lameness grade 2 (AAEP scale 1-5). Ground reaction forces (GRF) for individual limbs were calculated from kinematics. RESULTS: The horses significantly unloaded the painful limb by 11.5% at trot, while unloading at walk was not significant. The overall flexion-extension range of back motion decreased on average by 0.2 degrees at walk and increased by 3.3 degrees at trot (P<0.05). Changes in angular motion patterns of vertebral joints were noted only at trot, with an increase in flexion of 0.9 degrees at T10 (i.e. angle between T6, T10 and T13) during the stance phase of the sound diagonal and an increase in extension of the thoracolumbar area during stance of the lame diagonal (0.7degrees at T13, 0.8 degres at T17, 0.5 degres at L1, 0.4 degrees at L3 and 0.3 degrees at L5) (P<0.05). Lameness further caused a lateral bending of the cranial thoracic vertebral column towards the lame side (1.3 degrees at T10 and 0.9 degrees at T13) (P<0.05) during stance of the lame diagonal. CONCLUSIONS: Both range of motion and vertebral angular motion patterns are affected by subtle forelimb lameness. At walk, the effect is minimal, at trot the horses increased the vertebral range of motion and changed the pattern of thoracolumbar motion in the sagittal and horizontal planes, presumably in an attempt to move the centre of gravity away from the lame side and reduce the force on the affected limb. POTENTIAL RELEVANCE: Subtle forelimb lameness affects thoracolumbar kinematics. Future studies should aim at elucidating whether the altered movement patterns lead to back and/or neck dysfunction in the case of chronic lameness. 相似文献
8.
Reason for performing study: Saddle pads are widely used in riding sports but their influence on saddle pressures is poorly understood. Objective: To evaluate the forces acting on the horse's back, and the eventual pressure distribution by using different saddle pads underneath a fitting saddle. Methods: Sixteen sound horses of different breeds and ages were ridden on a treadmill at walk and sitting trot. The horses were wearing a dressage saddle with a fitting saddle tree and 4 different saddle pads (gel, leather, foam and reindeer fur) successively. For comparison, measurements were made without any saddle pad. Right forelimb motion was used to synchronise the pressure data with the stride cycles. A pressure mat was used under the saddle pad to collect the kinetic data. Maximum overall force (MOF) and the pressure distribution in longitudinal and transversal direction were calculated to identify differences between the measurements with and without saddle pads. Results: A significant decrease in MOF was interpreted as improved saddle fit, and a significant increase as worsened saddle fit. Only the reindeer fur pad significantly decreased the MOF from 1005 N to 796 N at walk and from 1650 N to 1437 N at trot compared to without pad measurements. None of the saddle pads increased the MOF significantly when compared to the data without saddle pad. The pressure distribution in longitudinal and transversal direction was also improved significantly only by the reindeer fur pad at trot compared to no pad. Conclusion: This study demonstrated that a well chosen saddle pad can reduce the load on the horse's back and therefore improve the suitability of a fitting saddle. 相似文献
9.
Trotting a horse in circles is a standard and important part of the subjective equine lameness examination, yet objective data on this form of locomotion are sparse. The aim of this study was to investigate the effect of trotting in a circle on head and trunk movement symmetry. Vertical movements of the head, withers, os sacrum and left and right tuber coxae were measured using inertial sensors as 12 sound horses were trotted on a hard surface in a straight line and in a circle on both reins. Seven asymmetry measures and hip hike were calculated for each horse for at least nine strides of comparable stride duration across the three conditions (deviation on horse level ≤3.7% stride duration). Trotting in a circle introduced systematic changes to the movement pattern of all five body landmarks, affecting most asymmetry measures. On average the asymmetry magnitude was comparable for midline locations between reins and for the tuber coxae on opposite reins with few exceptions, although individual horses showed unsystematic differences between the two reins. The results from this study showed that the thresholds for objective discrimination between lame and non-lame horses will need adjustment on the circle due to the observed asymmetry bias. 相似文献
10.
A. BYSTRÖM M. RHODIN K.
Von PEINEN M. A. WEISHAUPT L. ROEPSTORFF 《Equine veterinary journal》2010,42(4):340-345
Reasons for performing the study: The kinematics of the saddle and rider have not been thoroughly described at the walk. Objective: To describe saddle and rider movements during collected walk in a group of high‐level dressage horses and riders. Methods: Seven high‐level dressage horses and riders were subjected to kinematic measurements while performing collected walk on a treadmill. Movements of the saddle and rider's pelvis, upper body and head were analysed in a rigid body model. Projection angles were determined for the rider's arms and legs, and the neck and trunk of the horse. Distances between selected markers were used to describe rider position in relation to the horse and saddle. Results: During the first half of each hindlimb stance the saddle rotated cranially around the transverse axis, i.e. the front part was lowered in relation to the hind part and the rider's pelvis rotated caudally, i.e. in the opposite direction. The rider's seat moved forwards while the rider's neck and feet moved backwards. During the second half of hindlimb stance these movements were reversed. Conclusion: The saddles and riders of high‐level dressage horses follow a common movement pattern at collected walk. The movements of the saddle and rider are clearly related to the movements of the horse, both within and outside the sagittal plane. Potential relevance: The literature suggests that the rider's influence on the movement pattern of the horse is the strongest at walk. For assessment of the horse‐rider interaction in dressage horses presented for unsatisfactory performance, evaluations at walk may therefore be the most rewarding. Basic knowledge about rider and saddle movements in well‐performing horses is likely to be supportive to this task. 相似文献
11.
Akihiro MATSUURA Emiko OHTA Koichiro UEDA Hiroki NAKATSUJI Seiji KONDO 《Journal of Equine Science》2008,19(1):9-18
To obtain basic knowledge about selecting horses for therapeutic riding, the influence of
equine conformation on rider oscillation and relationships between these factors and the
evaluation on horses as the therapeutic riding were studied. Thirty-five riding horses
were used. Equine conformation was estimated by 24 indices. Rider oscillation was measured
by an accelerometer fixed at the rider’s waist. The spatial position of the oscillation
was estimated by a double integration of the acceleration. Horses were evaluated for
therapeutic riding by a Riding for the Disabled Association instructor as a rider.
Evaluations were on a scale of 1 to 5, with 5 being the highest score for 27 items. Horses
were classified into 4 groups: the short and narrow (SN), short and wide (SW), tall and
narrow (TN), and tall and wide (TW). The frequencies of rider oscillation both at walk and
trot were higher (P<0.01), and the vertical (P<0.01) and longitudinal (P<0.05)
amplitudes at trot were smaller, on short horses than on tall horses. The vertical
amplitude at walk was smaller (P<0.05) and the lateral amplitude at trot was larger
(P<0.01) on wide horses than on narrow horses. Short horses could be used for the rider
who requires side walkers. Wide horses could be used for relieving muscular tension and
for the rider who could not maintain good balance on the horse. Short and wide horses
should be suitable for therapeutic riding. 相似文献
12.
Mirjana Baban Ino Curik Boris Antunovic Mato Cacic Nidal Korabi Pero Mijic 《Journal of Equine Veterinary Science》2009
Besides being well known for their use in classical dressage, Lipizzaner horses are today becoming more and more popular for use in driving sport, with Croatia as the largest breeder in the world. To estimate their phenotypic predisposition for driving sport, this research analyzes the correlation between body measurements and traits of length and speed of walk and hand-led trot in 18 stallions (LS) and 53 mares (LM) by using a digital camera. Statistical analysis of the data concerning phenotypic correlations among the indicated traits has revealed the potential of documenting a large number of structural exterior body characteristics and quantitative measurements in Lipizzaner horses, and technical equipment has been found to be useful in research of stride traits. Higher withers height (WH) achieved through breeding was found to be negatively correlated with the number of strides per second during walk and trot, but positively correlated with walk stride length, especially in LS. Higher values for chest girth (CG) and cannon bone circumference (CBC) were found to be positively correlated with speed, as well as with stride length in LS, and negatively correlated with the number of strides per second during walk and trot in both LS and LM. Because for many years the goal of breeding Lipizzaners in Croatia has been to obtain a bigger body format and longer stride, leading to better results in a driving sport, these findings confirm breeding goals in selection work guided toward better stride length and extended stride as the most desirable traits for driving sport. 相似文献
13.
REASONS FOR PERFORMING STUDY: Diagnostic infiltration of local anaesthetic solution is commonly used in cases of equine back pain. Evaluation is subjective and it is not known how local analgesia of the back affects horses without clinical signs of back pain. OBJECTIVES: To evaluate the effect of infiltration of local anaesthetics on the movement of the back in horses without clinical signs of back pain, and to evaluate the usefulness of kinematic studies as an objective and quantitative tool in evaluating local analgesia in clinical practice. METHODS: The kinematics of the back in 10 clinically sound horses were measured on 2 occasions at walk and trot before and after injections with mepivacaine and sodium chloride around the interspinous spaces between T16 and L2. The kinematics were compared between the 2 occasions before injections and before and after each injection. RESULTS: The range of motion (ROM) for dorsoventral flexion-extension (FE) of the back was increased significantly in all measured segments other than T10 at walk, as was lateral bending (LB) at T10, L3 and L5 after injection of mepivacaine. For lateral excursion (LE), total movement increased at all measured segments. At trot the only affected segment was L3, where the injection with mepivacaine decreased the ROM for FE. After injection of sodium chloride the ROM for FE increased at T13 and T17 at walk. Lateral bending and LE were not affected at walk. At trot, LB increased at L3 and L5. CONCLUSIONS AND POTENTIAL RELEVANCE: Diagnostic infiltration of local anaesthetic solution affects the function of the back in clinically sound horses, which must be considered when interpreting the use of this clinical aid in assessing clinical cases of back dysfunction. Kinematics can qualitatively and quantitatively evaluate the effect of local analgesia of the back. 相似文献
14.
Reasons for performing study: Locomotion adaptation mechanisms have been observed in horses, but little information is available in relation to banked and nonbanked curve locomotion, which might be important to optimise training environments. Objectives: To determine if adaptation mechanisms in horses existed when moving on a banked compared to a flat curve and whether adaptation was similar in different gaits. Methods: Eight infrared cameras were positioned on the outside of a 10 m lungeing circle and calibrated. Retroreflective markers were used to define left and right metacarpus (McIII) and proximal phalanges (P1), metatarsus (MtIII), head and sacrum. Data were recorded at 308 Hz from 6 horses lunged at walk, trot and canter on a flat and 10° banked circle in a crossover design. Measurements extracted were speed, stride length, McIII inclination, MtIII inclination, relative body inclination and duty factor. Data were smoothed with a fourth order Butterworth filter with 30 Hz cut‐off. ANOVA was used to determine differences between conditions and limbs. Results: Adaptation mechanisms were influenced by gait. At canter inside forelimb duty factor was significantly longer (P<0.05) on a flat curve compared to a banked curve; at walk this was reversed. McIII inclination, MtIII inclination and relative body inclination were significantly greater (P<0.05) at trot and canter on a flat curve, so more inward tilt was found relative to the bearing surface. Conclusion: Adaptation to curved motion is gait specific. At faster gaits it appears that horses negotiate a banked curve with limb posture closer to body posture and probably with demands on the musculoskeletal system more similar to straight canter. 相似文献
15.
16.
M. A. Weishaupt A. Byström K. von Peinen T. Wiestner H. Meyer N. Waldern C. Johnston R. Van Weeren L. Roepstorff 《Equine veterinary journal》2009,41(3):263-267
Reasons for performing study: The load acting on the limbs and the load distribution between fore‐ and hindlimbs while performing specific dressage exercises lack objective assessment. Hypothesis: The greater a horse's level of collection, the more load is shifted to the rear and that during the passage the vertical load on the limbs increases in relation to the accentuated vertical movement of the centre of mass. Methods: Back and limb kinematics, vertical ground reaction force and time parameters of each limb were measured in 6 Grand Prix dressage horses performing on an instrumented treadmill at the trot and the passage. Horses were ridden by their own professional rider. Results: At the passage, horses moved at a slower speed (?43.2%), with a lower stride frequency (?23.6%) and, therefore, higher stride impulses (+31.0%). Relative stance duration of fore‐ and hindlimbs and suspension duration remained unchanged. While at the trot the diagonal limbs impacted almost simultaneously, the hindlimbs always impacted first at the passage; the time dissociation between landing and lift‐off remained unchanged. Because of the prolonged stride duration, stride impulse and consequently limb impulses were higher at the passage in the fore‐ as well as in the hindlimbs (+24.8% and +39.9%, respectively). Within the diagonal limb pair, load was shifted from the forehand to the hindquarters (percentage stride impulse carried by the forehand ?4.8%). Despite the higher impulses, peak vertical forces in the fore‐ and hindlimbs remained unchanged because of the prolonged absolute stance durations in fore‐ and hindlimbs (+28.1% and +32.2%, respectively). Conclusions: Based on the intralimb timing, the passage closely resembles the trot. Compared to other head‐neck positions, the higher degree of collection resulted in a pronounced shift in impulse towards the hindquarters. Despite the higher limb impulses, peak forces acting on the limbs were similar to those observed at the trot. Potential clinical relevance: An understanding of load distribution between fore‐ and hindlimbs in relation to different riding techniques is crucial to prevent wear‐and‐tear on the locomotor apparatus. 相似文献
17.
van Beek FE de Cocq P Timmerman M Muller M 《Veterinary journal (London, England : 1997)》2012,193(1):193-198
Injuries of horses might be related to the force the rider exerts on the horse. To better understand the loading of the horse by a rider, a sensor was developed to measure the force exerted by the rider on the stirrups. In the study, five horses and 23 riders participated. Stirrup forces measured in sitting trot and rising trot were synchronised with rider movements measured from digital films and made dimensionless by dividing them by the bodyweight (BW) of the rider. A Fourier transform of the stirrup force data showed that the signals of both sitting and rising trot contained 2.4 and 4.8 Hz frequencies. In addition, 1.1 and 3.7 Hz frequencies were also present at rising trot. Each stride cycle of trot showed two peaks in stirrup force. The heights of these peaks were 1.17±0.28 and 0.33±0.14 in rising and 0.45±0.24 and 0.38±0.22 (stirrup force (N)/BW of rider (N)) in sitting trot. A significant difference was found between the higher peaks of sitting and rising trot (P<0.001) and between the peaks within a single stride for both riding styles (P<0.001). The higher peak in rising trot occurred during the standing phase of the stride cycle. Riders imposed more force on the stirrups during rising than sitting trot. A combination of stirrup and saddle force data can provide additional information on the total loading of the horse by a rider. 相似文献
18.
Velocity-dependent changes in stride length and frequency were studied in 19 male foals, 6 to 8 months of age, and were related to body morphometrics. Eighteen distance and 8 angle measurements were digitized from 16-mm films of standing foals. The total mass and the percentage of total mass acting through the forelimbs were also recorded. Stride length and frequency data were extracted from 16-mm films of 239 strides of the walk, trot, and canter-gallop. Polynomial-regression analysis was used to determine the equation that best described the relationship between data of stride length or frequency vs velocity and stride length vs stride frequency for each foal, for the total population, and for the walk, trot, and canter-gallop data from the total population. Stepwise-regression analysis was done of stride length, or slope of the stride length-velocity line (frequency-1) vs distance, angle, and mass measurements. The stride length for each foal was calculated for a stride frequency of 2 strides/s. The maximum recorded velocity was 11.45 m/s. There was overlap in the velocity ranges at which gaits were used: the walk or trot were used at velocities between 1.7 to 2.0 m/s and a trot or canter were used over a wider velocity range of 3.2 to 5.8 m/s. Stride length did not exceed 4.72 m. The mean stride length at a frequency of 2 strides/s was 2.57 m and was significantly (P less than 0.05) correlated to total mass (r = 0.6335) and length of the metacarpus (r = -0.5115), but not to wither height.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
19.
K. von Peinen T. Wiestner S. Bogisch L. Roepstorff P. R. Van Weeren M. A. Weishaupt 《Equine veterinary journal》2009,41(3):285-291
Reasons for performing study: The exact relationship between the saddle pressure pattern during one stride cycle and the movements of horse and rider at the walk are poorly understood and have never been investigated in detail. Hypothesis: The movements of rider and horse account for the force distribution pattern under the saddle. Method: Vertical ground reaction forces (GRF), kinematics of horse and rider as well as saddle forces (FS) were measured synchronously in 7 high level dressage horses while being ridden on an instrumented treadmill at walk. Discrete values of the total saddle forces (FStot) were determined for each stride and related to kinematics and GRF. The pressure sensitive mat was divided into halves and sixths to assess the force distribution over the horse's back in more detail. Differences were tested using a one sample t test (P<0.05). Results: FStot of all the horses showed 3 peaks (P1‐P3) and 3 minima (M1‐M3) in each half‐cycle, which were systematically related to the footfall sequence of the walk. Looking at the halves of the mat, force curves were 50% phase‐shifted. The analysis of the FS of the 6 sections showed a clear association to the rider's and horse's movements. Conclusion: The saddle force distribution during an entire stride cycle has a distinct pattern although the force fluctuations of the FStot are small. The forces in the front thirds were clearly related to the movement of the front limbs, those in the mid part to the lateral flexion of the horse's spine and the loading of the hind part was mainly influenced by the axial rotation and lateral bending of the back. Potential relevance: These data can be used as a reference for comparing different types of saddle fit. 相似文献
20.
Flexion of the horse’s head and neck during dressage riding reduces the pharyngeal lumen with the risk of increased upper airway resistance and upper airway obstructions. According to the Fédération Equestre Internationale, hyperflexion is achieved through force, whereas the position low–deep–round is nonforced. The objectives of this study were to evaluate (1) applied rein tension and (2) dynamic structural disorders in the upper airways in dressage horses in different gaits and different head–neck positions (HNPs). Overground endoscopy (OGE) and rein tension were evaluated in 13 clinically healthy and high-performance Warmblood dressage horses while being ridden in a standardized program comprised of four different gaits (halt, walk, trot, and canter) and in four HNPs (unrestrained, competition frame, hyperflexion, and low–deep–round). All included horses were able to achieve the desired HNPs. The HNP low–deep–round showed significantly lower rein tension than competition frame (P < .001) and hyperflexion (P < .001). An association was found between dynamic structural disorders in the upper airway tract evaluated by OGE and head–neck flexion, but this association was not linked to the degree of flexion. The HNP hyperflexion was neither associated with greater rein tension nor severe dynamic structural disorders than the HNP competition frame. This study confirms that low–deep–round is a nonforced position, in contrast to hyperflexion. Further studies are needed to evaluate whether dynamic structural disorders are a result of flexion or if the degree of flexion has an impact. 相似文献