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Stuttgart, Germany

Lindner A.E.,Arbeitsgruppe Pferd
Journal of Animal Science | Year: 2010

The speed producing the maximal lactate steady state (maxLASS) is supposed to be the optimal speed to condition for endurance. The maxLASS was defined as the maximal speed at which the blood lactate concentration ([LA]) between the 5th and the 25th min of continuous exercise did not increase by more than 1 mmol/L. According to the aerobic-anaerobic lactate threshold concept determined in humans, maxLASS corresponds to v4 [speed in a standardized exercise test (SET) shown to produce an [LA] of 4 mmol/L; generalized to vi for the speed producing an [LA] of i mmol/L]. Four Thoroughbreds were submitted to a treadmill-based SET to determine their blood lactate-running speed (BLRS) relationship and calculate the individual v1.5, v2, v2.5, v3, and v4 values (velocities run under defined conditions inducing 1.5, 2, 2.5, 3, and 4 mmol/L of blood LA). Afterward, horses ran on the treadmill for 40 min at their v1.5, v2, and v2.5 every 3 d. Another 14 horses were submitted to SET in the field to determine their BLRS relationships and to calculate their v2. The day after the SET, these horses ran once between 15 and 30 min at their v2. In the horses that ran on the treadmill, maxLASS only occurred when running at their v1.5. Blood [LA] did not increase by more than 1 mmol/L between the 10th min and the end of exercise for all the horses that ran in the field at their v2. These data indicate that maxLASS of horses is not greater than v2 and therefore less than in running humans. ©2010 American Society of Animal Science.

Lindner A.E.,Arbeitsgruppe Pferd
Journal of Animal Science | Year: 2010

The objective of the study was to examine the validity of v4 [velocity run under the defined conditions inducing 4 mmol/L of blood lactate concentration ([LA])] and v200 (velocity run under the defined conditions inducing a heart rate of 200 beats/min) to differentiate performance level among Standardbred racehorses. For this purpose, 19 Standardbred trotting racehorses with differing racing time records in 2 training yards were submitted to a standardized exercise test to determine their v4 and v200 (6 horses of one yard only). The test consisted of 4 or more consecutive intervals depending on when the blood [LA] of a horse increased above 4 mmol/L. Speed and time trotted in each interval as well as time between consecutive intervals were the same for horses of a training yard. The blood [LA] measured after each interval was plotted exponentially against running speed to derive v4 from the blood lactate-running speed relationship, and the mean heart rate during the intervals was plotted linearly against running speed to derive v200 from the heart rate-running speed relationship. The correlation coefficient between v4 and the racing time record was 0.77 and 0.75 for horses in racing yard A and B, respectively. There was no correlation between v200 and the racing time record. Therefore, v4 is a valid indicator of performance level of Standardbred trotting racehorses; however, v200 may not be or to a lesser extent. © 2010 American Society of Animal Science.

Lindner A.,Arbeitsgruppe Pferd | Lopez R.A.,National University of La Plata | Durante E.,National University of La Plata | Hernandez H.,National University of La Plata | And 3 more authors.
Journal of Animal Physiology and Animal Nutrition | Year: 2011

This study examined the effect of exercising horses five times per fortnight with two bouts of 5min duration at their v10 with 2days between consecutive exercise sessions. Five Anglo-Arabian horses were treadmill-conditioned for 6weeks. A standardized exercise test (SET) was performed at the beginning of the conditioning period (CP) to determine the blood lactate-running speed (BLRS) and the heart rate-running speed (HRRS) relationship and the SET was repeated every 2weeks. After each SET, the BLRS relation was used to calculate the horse's speed (v = velocity), which produced a blood lactate concentration (LA) of 10mmol/l (v10) and 4mmol/l (v4). From the HRRS was calculated the speed at which the horses had a heart rate of 180 b/min (v180). Each horse was then conditioned for the next 2weeks five times at its individual v10 for two 5-min bouts. Exercise speed was individually adapted to the new v10 every 2weeks. In addition, horses were submitted to another SET prescription to determine the peak oxygen consumption (VO2peak) before, after 3weeks and at the end of CP. The v4 of horses increased during the CP (p<0.05). v180 did not change (p>0.05). VO2peak increased in the first 3weeks of CP (p<0.05) and levelled off afterwards (p>0.05). The conclusion drawn was that exercising horses five times per fortnight at their v10 for two 5-min bouts with 2days between consecutive exercise sessions improved v4 and VO2peak but not v180. © 2010 Blackwell Verlag GmbH.

Lindner A.,Arbeitsgruppe Pferd | Waschle S.,Arbeitsgruppe Pferd | Sasse H.H.L.,Justus Liebig University
Journal of Animal Physiology and Animal Nutrition | Year: 2012

The blood lactate concentration (LA) and heart rate (HR) of 10 horses exercising in water on a treadmill were examined. With the water at 10 and 50% of the withers height (WH), the blood LA increased up to mean values around 1.9mm during the standardized exercise test (SET) until after step 3 of 5 (each step lasted 5min, speed increasing step by step). Thereafter, blood LA of horses remained constant, while with the water at 80% of WH, the blood LA decreased from the mean peak of 2.16±0.62mm after the 4th step. The HR of the horses increased to 132±14beats/min until the 3rd step of SET with the water at 10% of WH, up to the 2nd step with the water at 50% (134±10beats/min) and up to the 1st step only with the water at 80% of WH (134±10beats/min). In another SET, horses were exercised five times for 5min at the maximal attainable speed of 5.5m/s in water at 20% of the withers height in step 1, 35% in step 2, 49% in step 3, 63% in step 4 and 77% in step 5. On using this SET, blood LA increased to 1.91±0.25mm until after the 2nd step and decreased after the 3rd step. The HR increased between before commencing SET and the 1st step (143±13beats/min) and remained constant thereafter. In conclusion, increasing water height and speed of exercise does not augment continuously blood LA and HR of horses exercising in water treadmills. © 2011 Blackwell Verlag GmbH.

Lindner A.,Arbeitsgruppe Pferd | Dag Erginsoy S.,Kafkas University | Kissenbeck S.,Arbeitsgruppe Pferd | Mosen H.,Arbeitsgruppe Pferd | And 4 more authors.
Journal of Animal Physiology and Animal Nutrition | Year: 2013

Summary: The effects of three different blood-guided conditioning programmes on ultrastructural and histochemical features of the gluteus medius muscle of 2-year-old sport horses were examined. Six non-trained Haflinger horses performed three consecutive conditioning programmes of varying lactate-guided intensities [velocities eliciting blood lactate concentrations of 1.5 (v1.5), 2.5 (v2.5) and 4 (v4)mm respectively] and durations (25 and 45min). Each conditioning programme lasted 6weeks and was followed by a 5-week resting period. Pre-, post- and deconditioning muscle biopsies were analysed. Although training and detraining adaptations were similar in nature, they varied significantly in magnitude among the three different conditioning programmes. Overall, the adaptations consisted in significant increases in size of mitochondria and myofibrils, as well as a hypertrophy of myofibrillar ATPase type IIA muscle fibres and a reduction in number of type IIx low-oxidative fibres. Together, these changes are compatible with a significant improvement in both muscle aerobic capacity and muscle strength. The use of v1.5 and v2.5 as the exercise intensities for 45min elicited more significant adaptations in muscle, whereas conditioning horses at v4 for 25min evoked minimal changes. Most of these muscular adaptations returned towards the pre-conditioning status after 5weeks of inactivity. It is concluded that exercises of low or moderate intensities (in the range between v1.5 and v2.5) and long duration (45min) are more effective for improving muscle features associated with stamina and power in sport horses than exercises of higher intensity (equivalent to v4) and shorter duration (25min). © 2012 Blackwell Verlag GmbH.

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