Randomized Cross-over Study
Phase: NA
Conditions: HIIT
Sponsor: Kastamonu University

Official Title: Effect of different work-to-rest ratios during simulated taekwondo combat on 
blood lactate, heart rate and perceptual responses in elite taekwondo athletes  
NCT Number: 2022-KAEK-12  
Date of the Document: 24th of February 2022  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  

Study Design  
This randomized cross-over study measured physiological and perceptual responses of 
taekwondo athletes following a free combat and combats with different W:R ratios. This study 
was carried out with 4 visits. The first one included body composition measurements and 
familiarization to the sessions and measurements. During the rest 3 visit, athletes performed 
simulated combats free and with 1:2 (10 sec work and 20 sec rest), and 2:1 (20 sec work and  
10 sec rest) W:R ratios. During all combat sessions, athletes heart rate (HR), blood lactate 
(bLA), and counter-movement jump performance (CMJ) were measured at rest and at the end 
of each combat. HR was also measured following each set. Athletes’ rating of perceived 
exertion (RPE) and perceived muscle soreness (PMS) were measured immediately after each 
combat.   
Statistical Analysis  
The data were analysed using SPSS 23 software (SPAA, Inc., Chicago, IL, USA) and JASP 
software (0.15.0.0 Version, The Netherlands). The Shapiro-Wilk test and descriptive methods 
using skewness and kurtosis coefficients were used to check for the normality of data. 
Descriptive statistics and 95% confidence intervals (CI) were used to present subjects' 
characteristics. Two-way ANOVA with repeated measurements (intervention x time) was used 
to determine changes in HR (3 x 4), bLA (3 x 2), CMJ (3 x 2) between W:R ratios and 
measurement times. One-way ANOVA was used to determine changes in PMS. Partial eta 
squared ( 2) was calculated to determine the effect size, using the 0.0099, 0.0588, and 0.1379 
considered as small, medium, and large effect sizes. In case of significant differences between 
W:R ratios, paired sample t-test was used, while one-way repeated measures ANOVA was used 
to determine the difference among measurement times. Cohen’s d for paired sample t-test was 

automatically provided by JASP software and classified as 0.2 (small), 0.5 (medium) and 0.8 
(large). Statistical significance was set at p<0.05.