The aim of the present work was to analyse the alterations of rhino-sinusal physiology in 106 professional athletes (swimmers, skiers, boxers and runners) using objective rhinological methods. Every athlete underwent an accurate anamnesis, a complete objective ORL evaluation, an active anterior rhinomanometry, an acoustic rhinometry and an evaluation of mucociliary transport time (MCTt). Skiers were also submitted to a nasal decongestion test (NDT). In swimmers, the mean MCTt was 27.4+/-4.97 min (normal value: 13+/-3 min; P<0.0001). The average MCTt for the skier group was 19.58+/-1.92 min ( P<0.0001); the mean value of total basal nasal resistance was 0.37+/-0.05 Pa/ml per s (normal value =0.25 Pa/ml per s; P<0.001). After NDT, total nasal resistance was 0.18+/-0.02 Pa/ml per s. In the group of boxers, the total mean nasal resistance was 0.64+/-0.05 Pa/ml per s ( P<0.001); the mean cross-sectional area at the nasal valve level was 0.57+/-0.04 cm(2) (normal value =0.55+/-0.05 cm(2)) and at the inferior turbinate level 0.83+/-0.05 cm(2) (normal value =0.4+/-0.04 cm(2); P<0.001); the TMC average time was 27.35+/-2.21 min ( P<0.0001). Finally, for the runners, the mean MCT time was 20.56+/-2.35 min ( P<0.001). Knowing the alterations of the physiological nasal respiration is of extreme importance to develop a correct and timely therapeutic approach to be able to restore rhino-sinusal homeostasis. Athletes, in fact, need the earliest therapeutic aid in order to avoid the interference of prolonged rhino-sinusal alterations with their performance and also to avoid a more serious clinical situation concerning the inferior airways.