A three-loop serpentine is a series of three, equal-sized half circles which form an ‘S’ shape across the arena.
Start this exercise in walk, to allow you more time to perfect your aids and your horse’s flexion (and build their muscles) before riding a three-loop serpentine in a working trot, and finally in canter.
Begin riding the serpentine at either A or C, and know the markers you are riding to before you begin. It can be a good idea to place markers on the centre line to help get your ‘eye’ in and ensure you are riding three equal loops.
To create the first loop ride a half circle, making sure that your horse is bending through his body around your inside leg. Do not ride into the corners of the arena as you are riding a half-circle.
Keep your outside leg on your horse, slightly behind the girth to control the quarters and to stop them from swinging out.
Your inside rein should be used to create a small amount of flexion to the bend through the horse’s neck. Maintain a soft, supportive outside rein to ensure his shoulder does not drift out.
At the centre line, your horse should be straight for approximately one horse’s length. Aim for your horse to be completely straight directly on the centre line.
Then, reverse your aids to change the flexion (if you’re riding the exercise in trot, don’t forget to change your diagonal). Ride a second half-circle of the same size and come back across the centre line straight before completing your third half-circle.
As with any exercise, it is important to practise this on both reins. Remember your horse will usually find one rein easier than the other and it may take time for them to get supple on both reins.
In lower level dressage tests three or four loop serpentines are usually ridden in trot. At more advanced levels these are ridden in collected canter with simple or flying changes each time you cross the centre line.