Saliva is one of the body's biological fluids, composed of proteins, glycoproteins, electrolytes and small organic molecules. The identification and the study of structural and functional changes of it is important for the health of athletes. The present study investigated the effect of one Concurrent training session (concurrent strength and endurance) on flow rate and biochemical composition of saliva (sodium, calcium, magnesium, potassium, phosphate, urea and total protein) and salivary hormone Cortisol and DHEA. In this study, 20 male athletes of Qaemshahr free University (mean aged 2 ± 23 years) participated for 100 minutes in Concurrent exercises. Participants' Diet and activities were controlled, 48 hours before and 24 hours after the race and non-stimulated salivary samples were collected for measurement in three time stages, before, immediately and 24 hours after the race. To analyze the data, Mauchly test, repeated ANOVA test, post hoc tests and SPSS16 software (significant level P�?�?��?�?0/05) were used. Findings showed that one session Concurrent exercise caused a significant decrease in concentration of electrolytes such as Sodium, calcium, magnesium, salivary flow rate and a significant increase in such electrolytes as potassium, total protein following the exercise. On the other hand the amount of phosphate and salivary urea has increased following exercises, but not statistically significant. Cortisol and DHEA levels have also a significant increase and decrease simultaneously after the activity (P�?�?��?�?0/05). 24 hours after exercise, except the amount of salivary flow rate, cortisol and DHEA, all electrolytes were partially returned to baseline. According to the results of this study, it can be said that physical activity, suppresses hormone production and Hydration may result into the reduction of salivary flow and undesirable changes in salivary electrolytes and provide the base for suppression of the mucosal immune system of athletes.
