BANFI, G. Serum creatinine concentrations in athletes: are they normal? Brazilian Journal of Biomotricity, v.
4, n. 3, p 157-164, 2010. In sports medicine, creatinine is used for evaluating general health status of
athletes. In the present review, different aspects of the behaviour of creatinine values in sportsmen are
summarized. The reference values for common biochemical and haematological parameters used for
athletes are the same commonly used for general population. The serum concentration of creatinine could
sometimes apparently pathological in some athletes and the interpretation of these values should consider
the sportsmen status. In fact, the values of serum creatinine in athletes are higher than those reported in
sedentary people. However, the population of sportsmen is not homogeneous, and some differences are
evident among athletes competing in different sport disciplines. The creatinine values are affected from
acute exercise, which modifies renal flow. The sport discipline is an additional variable for interpreting
creatinine values, which can show values lower than those measured in sedentary people in endurance
athletes. The creatinine values are modified in some sport disciplines during competitive season, showing
increases when activity is more intense. Cystatin C, a low molecular weight that is freely filtered through the
glomerulus and almost completely reabsorbed and catabolized by tubular cells, could be used in athletes,
while it is virtually independent from body mass.
