We investigated whether the total protein concentration of whole saliva would reflect the anaerobic threshold during an incremental exercise test with professional soccer players receiving carbohydrate and creatine supplementation. Twenty healthy men, no smoking, professional soccer players performed a test in the cycle ergometer with incremental load of 25 watts (W) every two minutes. In the first step, the subjects were submitted to a test to determine the heart rate, maximal load and VO₂. In the second step, 10 minutes after a protocol to depleted muscle glycogen, they receive a supplementation of 0.8g/Kg of carbohydrate and 5g/Kg of creatine followed to the same test.   Blood and stimulated saliva were collected during the test to measure the lactate and salivary total protein concentration. The relationship of salivary protein and blood lactate during the exercise test was observed with the results of each subject. The lactate and protein threshold were indicated in a certain W where represent the points of inflection at the transition from the linear to exponential portion of the curve.  Therefore, the increase of salivary protein concentration during the exercise was strongly correlated with blood lactate anaerobic threshold (r=0,95, p<0,05).  The average lactate level in the second step was lower indicating that the supplementation could increase performance and delay fatigue.  We suggest that measuring salivary total protein during incremental exercise is a putative non-invasive biomarker for determining the anaerobic threshold.