Abstract: Oxygen consumption (VO2), ventilation (VE) and heart rate (HR) were studied in five recreational riders with a portable oxygen analyser (K2 Cosmed, Rome) telemetric system, during two different experimental riding sessions. The first one was a dressage session in which the rider successively rode four different horses at a walk, trot and canter. The second one was a jumping training session. Each rider rode two horses, one known and one unknown. The physiological parameters were measured during warm up at a canter in suspension and when jumping an isolated obstacle at a trot and canter. This session was concluded by a jumping course with 12 obstacles. The data show a progressive increase in VO2 during the dressage session from a mean value of 0.70 (0.18) l x min(-1) [mean (SD)] at a walk, to 1.47 (0.28) l x min(-1) at a trot, and 1.9 (0.3) l x min(-1) at a canter. During the jumping session, rider VO2 was 2 (0.33) l x min(-1) with a mean HR of 155 beats x min(-1) during canter in suspension, obstacle trot and obstacle canter. The jumping course significantly enhanced VO2 and HR up to mean values of 2.40 (0.35) l x min(-1) and 176 beats x min(-1), respectively. The comparison among horses and riders during the dressage session shows differences in energy expenditure according to the horse for the same rider and between riders. During the jumping session, there was no statistical difference between riders riding known and unknown horses. In conclusion these data confirm that riding induces a significant increase in energy expenditure. During jumping, a mean value of 75% VO2max was reached. Therefore, a good aerobic capacity seems to be a factor determining riding performance in competitions. Regular riding practice and additional physical training are recommended to enhance the physical fitness of competitive riders.

Abstract: REASONS FOR PERFORMING STUDY: Force transmission under an English saddle (ES) at walk, trot and canter is commonly evaluated, but the influence of a side saddle (SS) on the equine back has not been documented. HYPOTHESIS: Force transmission under a SS, with its asymmetric construction, is different from an ES in walk, trot and canter, expressed in maximum overall force (MOF), force in the quarters of the saddle mat, and centre of pressure (COP). The biomechanics of the equine back are different under a SS compared to ES. METHODS: Thirteen horses without clinical signs of back pain ridden in an indoor riding school with both saddles were measured using an electronic saddle sensor pad. Synchronous kinematic measurements were carried out with tracing markers placed along the back in front of (withers, W) and behind the saddle (4th lumbar vertebra, L4). At least 6 motion cycles at walk, trot and canter with both saddles (ES, SS) were measured. Out of the pressure distribution the maximum overall force (MOF) and the location of the centre of pressure (COP) were calculated. RESULTS: Under the SS the centre of pressure was located to the right of the median and slightly caudal compared to the COP under the ES in all gaits. The MOF was significantly different (P<0.01) between saddles. At walk, L4 showed significantly larger (P<0.01) vertical excursions under the ES. Under the SS relative horizontal movement of W was significantly reduced (P<0.01) at trot, and at canter the transversal movement was significantly reduced (P<0.01) . In both trot and canter, no significant differences in the movement of L4 were documented. CONCLUSIONS AND POTENTIAL RELEVANCE: The results demonstrate that the load under a SS creates asymmetric force transmission under the saddle, and also influences back movement. To change the load distribution on the back of horses with potential back pain and as a training variation, a combination of both riding styles is suitable.

Abstract: The objective was to evaluate the efficacy of gymnastic training (GYM) and dynamic mobilization exercises (DMEs) on stride length (SL) and epaxial muscle size in therapy horses. Nine cross-bred hippotherapy horses that performed three, 25-minute therapeutic riding sessions per week throughout the study period were randomly assigned to three experimental groups: a control group in which the horses were sedentary with no additional physical activity; a group that performed DMEs; and a group that performed both DMEs and additional GYM including pelvic tilting, backing, turning in small circles, and walking over a raised rail to strengthen the abdominal and pelvic stabilizer muscles. The exercises were performed 3 days per week for 3 months, with evaluations at the start and end of the study. Stride quality was assessed by measuring SL and tracking distance (TD). Epaxial muscle size was monitored by ultrasonographic measurement of m. longissimus dorsi (LD) thickness and m. multifidi (MM) cross-sectional area. Paired t tests were used to compare within groups across time, and between groups were detected using analysis of variance with Tukey post hoc test. When walking at 1.3 m/s, SL and TD at walk increased significantly (P < .05) in horses subjected to GYM. Thickness of LD did not change in any group, but cross-sectional area of MM increased significantly by 3.55 cm2 (DME) and 3.78 cm2 (GYM). It was concluded that GYM training improved stride quality and DME-stimulated MM hypertrophy which has been shown to improve intervertebral joint stability in other species.

Abstract: This article traces the history of scientific and empirical interval training. Scientific research has shed some light on the choice of intensity, work duration and rest periods in so-called 'interval training'. Interval training involves repeated short to long bouts of rather high intensity exercise (equal or superior to maximal lactate steady-state velocity) interspersed with recovery periods (light exercise or rest). Interval training was first described by Reindell and Roskamm and was popularised in the 1950s by the Olympic champion, Emil Zatopek. Since then middle- and long- distance runners have used this technique to train at velocities close to their own specific competition velocity. In fact, trainers have used specific velocities from 800 to 5000m to calibrate interval training without taking into account physiological markers. However, outside of the competition season it seems better to refer to the velocities associated with particular physiological responses in the range from maximal lactate steady state to the absolute maximal velocity. The range of velocities used in a race must be taken into consideration, since even world records are not run at a constant pace. Copyright 2001 Adis International

Abstract: 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.