The effects of treadmill inclination and speed on the activity of two hindlimb muscles in the trotting horse

Abstract

Electromyographic activity (EMG) was used to determine how hindlimb muscle activation patterns vary with speed and incline in the horse. EMG was recorded using surface electrodes over the gluteus medius and tensor fasciae latae muscles during treadmill locomotion at trot for different combinations of speed (3.5 to 6 m/s) and inclination (0, 3 and 6%). Raw EMG signals were processed to determine stride duration, activity onset and end, and integrated EMG (IEMG). Stride and stance phase duration decreased linearly with increasing speed. Stride duration was not influenced by the slope. Onset and end of muscle activity came significantly earlier in the stride cycle when speed increased and later when inclination changed from 0 to 6%. The relative duration of the burst (percentage of stride duration) increased as running speed increased, but tended to decrease with increasing slope. The IEMG of the muscles increased with increasing speed and slope, the largest increase being observed in the tensorfasciae latae. It is concluded that both increases in speed and inclination lead to an increase in the integrated electromyographic activity and hence to a higher workload of the 2 hindlimb muscles investigated.

Effects of trotting speed on muscle activity and kinematics in saddlehorses

“…Self-adhesive Ag-AgCl surface electrodes 1 were fixed at a determined site for each muscle (Robert et al 2000(Robert et al , 2001a. A single reference electrode was placed over the right tuber sacrale.…”

Use of electromyography to detect muscle exhaustion in finishing barrows fed ractopamine HCl1

“…Fatigue in other livestock species has been measured via EMG (Girsch et al, 1995;Robert et al, 2000;Lee et al, 2013;Rajapaksha and Tucker, 2014), but these studies did not explore the biological characteristics of the muscle responsible for fatigue. Therefore, the objectives of this study were to use a RAC diet feeding model to induce muscle exhaustion in barrows, measure muscle fiber activity via EMG, and relate differences in exhaustion to muscle fiber type characteristic differences.…”

The metabolic cost of walking on gradients with a waddling gait

“…Ascending an incline should be more mechanically costly than locomotion on level ground, because of the requirement for additional work to increase the potential energy of the centre of mass (CoM) as it ascends the slope (Parsons et al, 2008). To produce this extra mechanical work, a greater volume of limb muscle may be recruited de Leon et al, 1994;Gardiner et al, 1982;Leroux et al, 1999;Pierotti et al, 1989;Robert et al, 2000;Roy et al, 1991) or muscle-shortening strains increased (Gillis and Biewener, 2002). Additional muscle activity means that whole-animal metabolic costs (rate of O 2 consumption, V O2 ) should also increase (Ellerby et al, 2003), assuming that additional costs are met aerobically.…”