It is a preparatory stage for making the body flexible for other dance forms with yogic postures that are particularly matched with dances, usually performed by kids. The mati akhora practised in sattras is known as Karan in Bharat's Natyashastra. In Bharat's shastra there are 108 karans, whereas in mati Akhora there are 70 postures. It is the beginner's stage of Sattriya dance. The main focus is Sarir Sadhana, i.e. flexibility of muscles etc. There is a close link with yogic postures; therefore it is more prevalent in the udasin (celibate) Sattras. This dance form in a larger sense is transformed in to the Borpravesh dance in bhaona; a particular dress code is also followed. After mati akhora the disciple is known as "Natua". The next stage of dance is nadu bhangi and Jhumura dance after which is the Bihar dance and chali nach up to a certain age of 18 to 20. After that they are retired from dances. However in the dances required for Bhaonas such as Sutradhar, Krishna, Ram, Lakhman; they still perform and dance till the age of 30. If they want to become gayan, or bayan then they are taught these forms after they retire at 20. They finally can become Borbayan or the professor of these tenets in a later stage as per heredity of the Sattra culture.
These are practices for hand movements to be used in various dance forms and to play various instruments. The young Bhakats from the age of 7 - 8 years are taught to play instruments such as khol, mridanh, tall etc. One who can sing well is taught to become a gayan and the other for bayan for showing expertise in playing these instruments. There are certain rituals in choosing and making the disciples Bayan and Gayan. Their examination is attended by the Sattradhikar, Burhabhakt, Borbayan and Bor gayan; if passed he offers betel/areca nut with paan as dakshina and is now regarded as Bayan.
After this exam he is taught the 12 dhemalis of bor dhemali, ghosa Dhemali, Borpetia Dhemali, Ram dhemali, Na dhemali, Cho dhemali, Guru mridang dhemali, Bong dhemali, Khatpravesh dhemali, Raag dhemali. The last one is Ghosa Dhemali. Following this, the Borgeets and Ankiya Geets are taught. During this time he accompanies the Borbayan in all respects to learn all the rituals that are required.
RAAG - RAGINI
There are two types of raags in sattriya form; Mela raag and Bandha raag. Mela raag is mostly for sattriya songs and Bandha raag for Ojhapaalis.
However, 56 raagas followed by the Garg Samhita are also mixed along with it. The originator of mela raag is Madhavdev during 1390 saka - 1518 sakas. There are 32 mela raags and 40 bandha raagas. It is not sure who among Shankaradev's disciples has created most of the raagas, but there are similarities among the Indian Classical music as well; such as Ashowary- Asawari, Dhansri Dhanashri, Belowar Bilawal, Sindhura Sindhu, Gandhar Gandhari, Ahir Ahiri, Purbi Purabi, Bhatiyali Bhatiyar, Suhai Suhana, Mahur Marwa etc. Shankaradeva introduced 25 raagas and Madhavdeva 7 raagas in Sattriya borgeet and drama songs. They also follow time as per the mainstream practices.
This is for the gayans. However the Bayans also can learn how to sing and vice versa to generate synchronism. There are some medicinal plants and herbs mixed with honey to make the throat suitable for singing.