Effects of judo-specific resistance training on kinetic and electromyographic parameters of pulling exercises in judo athletes

Abstract

In judo, rapid force production during pulling movements is an important component of athletic performance, which is why this capacity needs to be specifically exercised in judo. This study aimed at examining the effects of a judo-specific resistance training program using a judo ergometer system (PTJ) versus a traditional resistance training regime using a partner (PTP) on kinetics and muscle activity of judo-specific pulling exercises. Twenty-four male judo athletes (age: 22 ± 4 years, training experience: 15 ± 3 years) were randomly assigned to two groups. In a crossover design, the first group completed a 4-week PTJ followed by four weeks of PTP (each with three sessions per week). The second group conducted PTP prior to PTJ. PTJ and PTP were completed in addition to regular training. Before, 4 weeks and 8 weeks after training, tests were conducted to assess judo-specific pulling kinetics (i. e. maximal force, rate of force development [RFD], mechanical work) and electromyographic (EMG) shoulder/trunk muscle activity (i. e. biceps brachii muscle, deltoid muscle, trapezius muscle, erector spinae muscle) during pulling movements using a judo ergometer as well as unspecific strength tests (i. e. bench-pull, pull-ups). The statistical analysis revealed that in both groups ergometer pulling kinetics (p <.05, 0.83 ≤d≤ 1.77) and EMG activity (p <.05; 1.07 ≤d≤ 2.25) were significantly enhanced following 8 weeks of training. In addition, significantly larger gains in RFD, mechanical work, and EMG activity (i. e. deltoid muscle, erector spinae muscle, trapezius muscle) were found following PTJ compared to PTP (p <.05, 1.25 ≤d≤ 2.79). No significant enhancements were observed with the unspecific strength tests. Our findings indicate that PTJ is superior to PTP regarding training-induced improvements in force production and muscle activity during judo-specific pulling exercises. Performance enhancements may partly be attributed to neural adaptations. No transfer effects on unspecific strength tests were detected following PTJ and PTP.