Neurobiochemical markers of brain damage, S100B and neurone specific enolase (NSE) have increased in interest in diagnostic clinical neurotraumatology (Herrmann et al., 2001). Serum S-100B is superior to NSE as an early prognostic biomarker for neurological outcome following cardiopulmonary resuscitation (Shinozaki et al., 2009). The aim of the study was to determine if S100B was a better indicator of neurological trauma than NSE by examining increased serum concentrations following technical knockouts (TKOs) in full contact karate. Twenty four full contact karate practitioners were divided into three groups retrospectively, post-combat: Technical Knockouts (TKO), (n=6, mean ± SD, age 33.5 ± 3.8 years), Kicks to The Head (KTH) (n=6, mean ± SD, age 27.3 ± 7.8 years), and Kicks to The Body (KTB) (n=12, mean ± SD, age 28.2 ± 6.5 years). The TKO and KTH groups both received direct kicks to the head, while group KTB received only blows to the body. Blood samples were taken before and immediately after combat for analysis of S-100B and NSE. In addition muscle damage was assessed by analysis of serum total creatine kinase (CK) and serum troponin was analysed to exclude cardiac muscle damage. Significant increases in serum concentrations of S-100B (p<0.05) were found immediately after combat within the TKO group (0.16 ± 0.25 vs 0.42 ± 0.39, µg.L-1). There were also significant differences (p<0.05) found between TKO, KTH and KTB groups (0.42 ± 0.39 vs 0.32 ± 0.14 vs 0.12 ± 0.16, µg.L-1). Significant increases (p<0.05) in NSE occurred only after combat in the TKO group (11.9 ± 5.9 vs 20.2 ± 11.4 ng.ml-1). There were significant increases (p<0.05) in CK in both the KTH and KTB groups post combat (KTH: 115.3 ± 61.4 vs 206.3 ± 131; KTB: 159.9 ± 88 vs 189.4 ± 99 U.L-1). Changes in concentrations of S-100B and NSE suggest TKOs involving head kicks in full contact karate cause biochemically discernible damage of brain tissue. However, S-100B proved more sensitive than NSE, despite both concentrations of analytes being elevated following head kicks not severe enough to result in a TKO, NSE was not elevated compared with kicks to the body. The severity of traumatic brain injury is associated with the early post-traumatic release of protein S-100B and NSE. S-100B is not affected by haemolysis and remains stable for several hours without the need for immediate analysis. Its short half-life and early kinetics of S100B after traumatic brain injury make measurements crucial in the accident and emergency care environment (Korfias et al., 2007). The first serum S-100B would appear to be more reliable as an early predictor of poor neurological outcome than NSE within 24 hours (Woertgen et al., 1997) and can reduce the need for CT scans or admission by over 30% (Springborg et al., 2009).