[Effect if 6-week nutritional intervention with enzymatic yeast cells and antioxidants on exercise stress and...

The aim of the present study was to investigate the influence of a yeast cell preparation rich in antioxidant vitamins, antioxidant enzymes, trace elements and minerals on the exercise-induced stress reaction and antioxidant status. The study was carried out in a non-blinded, controlled design. After a 6 week pre-ingestion period, 9 highly endurance-trained athletes took the preparation twice daily for another 6 weeks. After each phase venous blood samples were drawn in the resting state after an overnight fast followed by a strenuous 15 km cross country race. 1 h after the exercise venous blood sampling was repeated. Compared to the pre-ingestion period, the following significant alterations could be detected after 6 weeks of ingestion: 1) In the resting state, soluble interleukin-2 receptor (p < 0.05) and plasma fibrinogen (p < 0.01) were shown to be lower whereas plasma fibronectin was increased (p < 0.01). 2) 1 h after the race the significant difference in fibrinogen and fibronectin was confirmed. In addition myoglobin (p < 0.01) and CKMM3 (p < 0.05) as well as mangan superoxid dismutase (p < 0.05) were reduced. In conclusion, the 6-week ingestion-period resulted in an improvement of the systemic and muscular stress reaction. In addition, the decrease in mangan superoxide dismutase concentration can be interpreted as a sign of reduced free radical stress. However, these preliminary results have to be confirmed in larger trials in blinded designs. In addition, there seems to be a rationale for testing the effects of yeast-cell preparations in patients with chronic degenerative diseases as some of the investigated parameters are involved in the pathophysiology of such illnesses.