Effect of repeated plyometric jumping exercise on gait variables of horses without rider

Responsibles
José Lucio Nuniez, Raul Signorini, Katia de Oliveira, Arno Lindner

Duration
Done 2016. Data being evaluated

Introduction
There are few studies on the training of horses used for show jumping (SJ; Art et al 1990 a, b; Barrey and Valette 1993; Müller 1993; Lopez-Rivero and Letelier 2000; Hedegaard et al 2014). Munk et al (2013) only have done an experimental study examining the effect of horses trained with different types of jumping exercise. Plyometric exercise is used in man to increase jumping force and might be a training instrument for horses too.
This study was done to examine the acute effect of repeating during an exercise session and on several days plyometric in-out jumping exercise on gait variables of horses without a rider. It was hypothesized that the gait variables would change over time.

Material and Methods

  • Six horses schooled for more than one year to jump different types of obstacles put in front of them in a track once left free by the handler.
  • A fenced circular track was prepared on an area of 40 x 109 m2 of compacted sand. The outer diameter of the track had a length of 39.4 m. On both ends of the track was an area sufficiently large for the horses to turn around and run back the track.
  • Thirteen obstacles were placed within the 1.8 m wide track. The obstacles consisted of 4 firmly welded barrels each 0.6 m high and 0.9 m long making an obstacle with a width of 1.2 m, a height of 0.6 m and a length of 1.8 m. The outer distance between obstacles was 3.8 m and the inner distance 2.6 m.
  • Horses were lunged for 10 minutes in a circle of 18 m diameter at the trot or canter depending on their preference before the jumping exercise.
  • The exercise consisted of a run where horses jump the 13 obstacles voluntarily forth and back at their preferred speed. Thus, a run consisted of 2 legs: one down and one back the track with the obstacles.

Study design

  • The 1st day of the study horses jumped one time the 13 obstacles forth and back (26 jumps).
  • The day thereafter horses did the same routine as on the 1st day, were then kept walking for 10 minutes and repeated the routine once (52 jumps in total).
  • On the 3rd day horses stayed in their paddocks and were not exercised.
  • On the 4th day horses did the same routine as in the 2nd day, were walked thereafter for another 10 minutes and did the routine one more time (total of 78 jumps).

Gait analysis

  • The gait analysis was done with a commercial accelerometric equipment (EquimetrixTM, Centaure Metrix, Fontainebleau, France). The gait variables measured were stride frequency, stride regularity, dorsoventral displacement, dorsoventral power and propulsion power.

Blood lactate concentration LA

  • After warm-up, within 20 s and 10 minutes after each run, the jugular vein was punctured and blood collected into 1 ml heparin coated syringes. Blood LA was measured immediately with the hand-held LA measuring device AccusportTM, Roche, Mannheim, Germany.