Physical exercise alters homeostasis, as it requires prompt mobilization of metabolic sources. In this study, we measured serum testosterone (T) and cortisol (C) levels and the muscle-wastage enzymes CK, CKMB and LDH in 20 healthy male athletes (ages 25 to 40 years) in response to a marathon race (42.2 km). Venous blood samples were drawn in 3 different periods: (i) in the morning, 48 h before the competition (control), (ii) at the end of the race (end), and (iii) in the next morning, 20 h after the race (recovery). At the end, T was significantly lower (from 673 to 303 ng/dl) and C higher (from 20.3 to 42.5 µg/dl) as compared to the control period. At recovery, both were virtually identical to control levels. CK, CKMB and LDH were significantly higher at the end of the competition and even higher in the recovering period (except for CKMB), characterizing muscle wastage. CK and LDH disclosed a significant negative correlation with T (-0.412 and -0.546, respectively), whereas CKMB correlated positively with C (0.4521). We conclude that the inverse correlation observed between T and C levels, and the pattern of CK, CKMB and LDH increase, allow us to confirm that a marathon race may cause a marked physical stress, resulting in a distinct hormonal imbalance and severe cellular damage.
Marathon; Testosterone; Cortisol; Muscle enzymes; Glycoprotein catabolism; Energy
