A local martial arts school I'm thinking of attending teaches hapkido 3 days a week which I'm interested in...two days a week they also teach the following (paraphrased)... 'Single and two person armed and unarmed yang style forms and basic sun style for those with arthritis or joint problems. Also Bagua and hsing yi' ....What exactly is all this? I'm more interested in the hapkido but if my 42 year old body can't take it this would be the next choice. Can you please explain as I'm not familiar with the internal arts except viewing it as an old persons art, not being biased just being honest.