Abstract

The purpose of the present study was to compare concentric electromyostimulation (EENM) versus voluntary training effects. 28 students were divided in three groups: EENM (GE; n=10), voluntary training group (GV, n=8) and control group (GC, n=10). Sixteen quadriceps training sessions were performed during four weeks. Each session consisted of 8 sets of 10 repetitions at 80% of the isometric maximum force (FMI) n a leg extension machine. The training rhythm was 1:1:1 (concentric, eccentric and rest phases, respectively). GE received EENM during the concentric phase. Before and after training period (T1 and T2, respectively) and after two detraining weeks (T3) sprint time in 20 m (T-20), three vertical jumps (SJ, CMJ and ABK) and FMI were measured. Between T1 and T2 an increased in FMI was observed both in GE and GV (39.2% y 30.1%, p<0.001), while in GE a decreased was detected in CMJ (-6.2%, p<0.01) and ABK (-7.5%, p<0.01). EENM concentric training is as effective as voluntary training to improve isometric maximum force, but it could be harmful for performance in some vertical jumps.