"Kasab does exercise and practises karate sometimes to kill his time. He also often strikes a conversation with the security guards deployed there to guard him round the clock," said a jail official.
The terrorist appears to be knowing karate kicks very well, the official said.
The lone surviving gunman is currently lodged in a strong bomb-proof "anda cell" inside the jail and process to shift him to the Yerawada central prison in Pune is underway.
After reviewing the security of Kasab at the Arthur Road jail, the police had moved a proposal to the government requesting the death-row convict be shifted to Yerwada, the biggest prison in the state.
The official further said Kasab talks a lot sometimes.
"However, security guards at the cell avoid speaking to him. He enquires the guards as to from where they are, since how long they were associated with security agencies and so on....," the official added.
The High Court had on February 21 upheld the death sentence to Kasab while dismissing Maharashtra government's appeal challenging the acquittal of Indian co-conspirators Faheem Ansari and Sabauddin Ahmed in the terror attack case.
He has decided to file an appeal in the Supreme Court challenging the judgement of the Bombay High Court confirming his sentence, awarded by a anti-terror court earlier.