(See Part 1)
The 20-meter circle is one of the most important training figures in dressage, first seen in the most simple tests possible, and continued on through Grand Prix. It is one of the first ring figures taught to beginner riders and young or green horses. Due to its size, it does not require that the horse or rider have incredible skills to ride moderately well, but circle-work should increase in quality as the horse and rider become more adept. This circle is a great test of the horse's suppleness and the rider's ability to keep the horse on the aids. Incorrect position or application of the aids, such as overuse of the inside rein, will often become apparent on the 20-meter circle.
The 20-meter circle fits very well into both the small (20 x 40 meter) and standard (20 x 60 meter) arenas, allowing the rider to use points on the wall to determine if the circle is the correct size and shape.
The 20-meter circle should be round, not egg or pear-shaped. This means that each side of the arena that touches the circle should only be met at a single point, and should not be ridden along for any period of time. Many novice riders go too deep into the corners of the arena, causing their circle to bulge out. Bulging or falling in both indicate that the horse is not correctly bent on the circle, or that he is leaning against the rider's leg and falling in or out.
The 20-meter circle can be used in all steps of training. Variations may include shoulder-in or haunches-in on the circle, transitions between and within gaits, extension and collection, and eventually something as advanced as flying changes, including tempi changes, on the circle
End of Part 2 - more to come ...