A speech recognition system is provided that, in one embodiment, includes an input 104 operable to receive voice utterances from a user, a speaker monitoring agent 132 operable to determine a pulmonary state of the user as a function of time, and a frame analyzer 120 operable to (i) determine a respective pulmonary state of the user at an approximate time when each of the voice utterances was made and (ii) process each of the voice utterance in a manner dependent upon the respective pulmonary state.