As with NaeGa ShinJang, the key functions of DaeDoh (big step) are natural abdominal breathing of each side of the belly (right and left abdomen) and YeokGeun of the horizontal muscles on the upper body. It brings about YeokGeun of the muscles surrounding the spine, greatly improving the flow of energy throughout the body.
DaeDohYeokGeun, an advanced pose of DaeDoh, requires great endurance and internal force to keep the YeokGeun in the upper body. This pose can help one normalize (or correct) any curved or crooked spine, scoliosis, back pain, slipped discs, arthritis, rheumatism, knee injuries, etc.
In general, other four basic GiCheon poses are not recommended to those with ailments (until one improves conditioning of the entire body through regular practice with WonBahnJang, DahnBaeGong, NaeGa ShinJang and DaeDoh) as follow: Back pain, Arthritis, Rheumatism,Joint pains and Spinal problems (Scoliosis, Slipped discs, etc), Sports injuries, Hypertension, Hypotension, Heart diseases, Diabetes, Asthma, Paralysis, Chronic aches and pains, etc.