The characteristics of phonation in different physiological states is an important task, which is engaged in both medical and phonetic studies. This paper examines the impact of physical stress on speech from the phonetic point of view. The main objective of this study is to identify the phonetic features of speech in the state of physical fatigue and before it. The speech material includes 8 speakers (4 male and 4 female) in two states - before physical exercises and after. In both states speakers were asked to read texts. A three-step analysis (auditory, acoustic and statistical) was conducted. The results of the acoustic and auditory analysis showed dependency between acoustic parameters and speech under physical stress in terms of fundamental frequency, as well as the duration of the phonemes. This study also takes into account the intensity of breath as an important component of speech after a physical task. After physical activity, a greater number and variety of speech disruptions appear in the speakers' speech, breathing becomes more frequent and more intense, more pauses appear, the duration of the sounds changes, and such phenomena as noisy final vowels, amplitude jumps and voice tremor appear.