Sandra Martins, Nuno Silva, Monica Sousa, Rita Pinto, Zosima Lima Pinto, Joao Tiago Guimaraes
Introduction: Physical activity as a preanalytical variable can influence several biomarkers. The level of training, type, intensity and duration of exercise may influence a broad array of laboratory variables. The aim of this study was to describe the changes of some common clinical chemistry in response to an exhaustion exercise protocol. Materials and methods: Thirteen adult male athletes participated in the study. A blood sample was collected with the athletes fasting and before exercise (M1). Then the participants completed an eccentric/concentric contraction knee extension/flexion exercise protocol until exhaustion. At this moment, a second blood sample was collected (M2). Protocol was repeated 2 weeks later and the mean of both measurements was considered for comparisons. Routine clinical chemistry parameters were analyzed in automated routine equipment’s. Wilcoxon test were used to compare mean differences between two moments. Results: As expected, there was an increase in muscle markers between M1 and M2 moments with significant differences for creatine kinase (P=0.023), C-reactive protein (P=0.033) and myoglobin (P=0.002). Also, were observed significant differences in GGT, Total-, HDL- and LDL-cholesterol (P=0.006, 0.015, 0.009 and 0.033, respectively) and with an acceptable biological variation bias. Beside the significant differences in both Moments, total protein (P=0.003), glucose (P=0.012), albumin (P=0.003), uric acid (P=0.001), magnesium (P=0.039) and phosphorus (P=0.001) exceed acceptable bias range. Conclusion: Our results show that even after an intense exhaustion physical exercise only a small group of parameters showed changes that exceed the acceptable biological variation bias. In conclusion, we expect that this study contributes to a better understating of the effects of an intense exhaustion physical exercise on common analytical biomarkers.