While practising yoga there are so many obstacles that may effect our physical  and mental health. And one of the them ,the most important is diseases which is also mentioned in gherunda samhita.

To over come this 'disease obstacle'our ancient guru's  have selected some
asanas,Mudras,pranayamas, meditation,Bandhas and shatkarmas ,which helps to overcome this. When we practice the above mentioned techniques they directly effect our body,which later came to be  known as yoga therapy.
Practicing shatkarma or shatkriya helps to clean our body and overcome diseases. Practicing few selected asanas,pranayams, mudras and editation  which directly effects our glands, organs and body parts where healing is needed. Our body is what we eat, so always select those food that nourishes our mind and body and even soul. Practicing yoga for particular diseases our guru's jas prescribed  some herbs also, which has tremendous healing effect.