Author(s): YUE, M.1, MANYING, R.2, Institution: BEIJING SPORT UNIVERSITY, Country: CHINA, Abstract-ID: 404

INTRODUCTION:
The Special Judo Fitness Test (SJFT) has been reported as the most widely used test in judo studies(1) due to its correlation with the number of attacks in a simulated combat scenario(2) its ability to effectively discriminate between judo athletes of varying competition levels and its simulation of a metabolic demand similar to that of an actual judo match(3).While the SJFT has shown correlations with some variables associated with aerobic(4,5) and anaerobic fitness(6,7), as well as lower body muscle power(5). Whether additional essential neuromuscular factors of upper body pull, torso, lower body or a combination of these variables could explain the better performance during SJFT is unclear.Therefore, the aim of this study was to identify the relationship of strength and power variables with SJFT performance and determine which variables could better explain the variance in SJFT performance.
METHODS:
All subjects performed the SJFT, a judogi pull-up, countermovement jump (CMJ), and torso isometric strength test. For the SJFT, the total number of throws, heart rate immediately and 1 minute after, and SJFT index were determined. For the judogi pull-up test, relative maximal time in isometric (IJPUT), mean velocity (DJPUV) and power (DJPUP) in single dynamic, and number of correct judogi’s pull-ups until failure (DJPUR) were determined. For the CMJ test, mean height (CMJMH) and loss of height between initial and final 10 jumps (CMJHL) were determined. For torso isometric strength test, relative peak torque in left lateral flexion (TFLRPT), right lateral flexion (TFRRPT), left rotation (TRLRPT), and right rotation (TRRRPT) were determined.
RESULTS:
Pearson’s correlation coefficient identified significant variables for inclusion in the stepwise multiple linear regression analysis, which showed that TFRRPT and DJPUP explained 77% (p = 0.000) of the total number of throws in SJFT variance and 57% (p = 0.002) of the SJFT index variance, respectively.
CONCLUSION:
Our findings suggest that several strength and explosive strength variables have a strong correlation with specific judo performance (SJFT). The mean power in single dynamic judogi pull-up and the relative peak torque of torso lateral right flexion could explain 77% of the variance of the total number of throws in SJFT and 57% of the SJFT index. The finding sheds light on the explosive strength profile of the upper body pull movement, which contributes a lot to this sport. Compared to the SJFT index, two variables can better predict the total number of throws in SJFT. This is because, in addition to the neuromuscular elements, the SJFT index is additionally affected by physiological factors, including aerobic and anaerobic metabolism.

1.Casals C et al.(2017) 2. Lwai K et al.(2008) 3. Franchini E et al.(2011) 4.Franchini E et al.(2008) 5.Hesari A et al.(2013) 6. Sterkowicz S et al.(2012) 7.Wolska B et al.(2010)