Background: Previous studies have shown the diagnostic relevance of the so-called free testosterone/cortisol ratio (FTCR). A condition of overtraining might indeed exist in an athlete when at least one of the two following criteria are observed: a) a FTCR value lower than 0.00035 (FT in nmol x L(-1) and C in micromol x L(-1)); and b) a decrease in the FTCR of 30% or more. On the other hand, no previous research has studied the incidence of overtraining in special military units as a result of their demanding training programs.
Hypothesis: A percentage of recruits of the Spanish special military Unit, "Grupo de Operaciones Especiales," (GOES) might be overtrained. It was the purpose of our study to analyze the effects on the FTCR of an intense physical training program performed by recruits of the GOES.
Methods: Before (PRE) and after (POST) an 8-wk training program, respectively, the following measurements were made in 42 recruits of the GOES: hematological and hormonal parameters (FTCR), aerobic and anaerobic tests, and strength and power tests.
Results: A high incidence (10 subjects, 23.8% of total) of overtraining existed among conscripts, as determined by the absolute criterium of a decline in the FCTR of 30% or more when comparing PRE and POST values. Additionally, overtraining was associated with a decrease in performance (i.e., isometric strength, vertical jump, Wingate tests).
Conclusions: In addition to some conventional measurements of performance, the FTCR might be used to monitor exercise training in military units, in order to prevent overtraining.