Warm-up

Exercises done before kumdo practice to bring the body from rest to a state of exercise and to help prevent injury. They combine stretching, general movements and movements used in the art itself.

Junbi undong (준비운동, "warm-up") is the set of exercises done at the start of kumdo practice, before the main training.

Purpose: the All Japan Kendo Federation, the source that explains this, says the aim is to lead the body's functions from rest to a state of exercise, so very intense exercise is not needed. A Korean Q&A answer also stresses that warming up is necessary to prevent injury.
Content: stretching, general calisthenics and movements used in the art itself.
Duration: the same source gives about 10 to 15 minutes, combining stretching with moderate joint bending, extending and rotating.
Order: a Korean forum answer (Daum) recommends starting with the parts farthest from the heart and moving toward the nearest. It names the wrists, neck, waist and ankles and singles out the Achilles tendon. This is one forum opinion, not an official rule.
Stretching: a Korean university kumdo club text gives these reasons to stretch before and after training: lower muscle tension, ease joint movement, avoid injury during exercise, signal the muscles that exercise is starting, relax mental tension and increase blood flow.
Link to basic drills: the Korea Kumdo Association (Daehan Geomdohoe) describes the three-movement drill (3동작치기) as a method used in the basic course or the warm-up stage. It splits the action into raising, striking and the middle guard (jungdanse, 중단세) to check posture.

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