Test-retest reliability and criterion validity of a new Taekwondo Anaerobic Intermittent Kick Test.

BACKGROUND: The aim of this study was to determine the relative and absolute test-retest reliability and criterion validity of a new Taekwondo Anaerobic Intermittent Kick Test (TAIKT). METHODS: Twenty Tunisian elite Taekwondo athletes participated in this study (15 males and 5 females). Participants performed the TAIKT and the Running-based Anaerobic Sprint Test (RAST), twice (test and retest), on separate occasions three-week apart. Peak heart rate (HRpeak), blood lactate concentration [LaÖ¾], and rating of perceived exertion (RPE) were measured during each session. RESULTS: There was no significant difference between the test and retest of TAIKT and RAST for all performances and physiological variables, except for the absolute mean power (Pmean) of RAST. Test-retest results showed that the TAIKT and RAST were reliable. All TAIKT and RAST parameters had an ICC>0.90, SEM<5%, with the smallest worthwhile change slightly higher than SEM, with very small limits of concordance. Strong significant correlations were found between TAIKT and RAST parameters (Ppeak (r=0.81; r=0.70), Pmean (r=0.72; r=0.60) in (W and W·Kg-67 respectively), fatigue index (r=0.81), [LaÖ¾] (r=0.89) and RPE (r=0.78) at P<0.01, and HRpeak (r=0.55, at P<0.05)). CONCLUSIONS: The findings showed that the TAIKT can be considered as a valid and reliable specific test for assessing anaerobic power of Taekwondo athletes.

One night of partial sleep deprivation increased biomarkers of muscle and cardiac injuries during acute intermittent exercise.

BACKGROUND: The aim of this study was to evaluate the effect of two types of partial sleep deprivation (PSD) on biomarkers of muscle and cardiac injuries in response to acute intermittent exercise in professional athletes. METHODS: In a counterbalanced order, ten healthy male Taekwondo athletes were asked to perform the Yo-Yo Intermittent Recovery Test (YYIRT) in three conditions, allowing a 36 h recovery period in between: 1) following a full night of habitual sleep known as a reference sleep night (RN); 2) following PSD in the beginning of the night (PSDBN); and 3) following PSD in the end of the night (PSDEN). Heart rate (HR) and arterial oxygen saturation (SaO2) were measured during exercise. Blood samples were taken just before and 3 min after the YYIRT to measure biomarkers related to muscle and cardiac injuries (BRMCI). RESULTS: No significant effect of PSD was observed for physiological parameters (i.e., HR and SaO2). However, a significant alteration of resting ultra-sensitive C-reactive protein (us-CRP) (P<0.05) and myoglobin (MYO) (P<0.01) levels was detected after PSDEN. Furthermore, all BRMCI were altered by exercise. Likewise, compared to RN, PSD affected creatine phosphokinase (CPK) and MYO levels in response to exercise (P<0.05). CONCLUSIONS: The present study indicates that PSDEN increase the resting us-CRP and MYO levels, and that the two types of PSD increase the CPK and MYO levels in response to acute intermittent exercise, among Taekwondo athletes, in the evening of the following day. However, no rise of the physiological responses has been observed after the two types of PSD, at rest and in response to the exercise.