Volleyball is a sport involving short and intensive physical efforts during training and competition [1,2]. Volleyball players' fitness relies on their force, power output and jumping ability [3,4]. Although the players' power output is measured on a cycloergometer, its value depends, however, on the amount of external loading [2]. Different authors have examined the force-velocity (F-v) and power-velocity (P-v) relationships, measured during cycloergometer exercises in different groups of athletes [5,6] and discussed the effects of specific training exercises on the force-velocity relationship [7][8][9]. Their results suggest that sport training can influence the correlation mentioned [5][6][7]. With the exception of Häkkinen's work [10] discussing changes of force and jumping ability in female volleyball players during the competitive season, there have been no studies, however, examining changes in the force-velocity and power-velocity relationships in volleyball players during an annual training cycle. The aim of the present study was to follow changes of the maximal power output and powervelocity relationship in male volleyball players during an annual training cycle.
Material and methodsThe study was granted approval of the Research Ethics Committee. The sample consisted of six male volleyball players from the Polish Volleyball League aged 25.0 ± 5.3 years, with body height of 195.2 ± 7.2 cm and body weight of 91.2 ± 14.7 kg. The measurements were performed before the preparatory period (I), after the first competitive season (II) and after the second competitive season (III).The force-velocity (F-v) and power-velocity (P-v) relationships were determined on the basis of results of exercises performed on a Monark 874 E cycloergometer connected to a PC, using the MCE 4.0 software package. After adjusting the ergometer saddle and handlebars each subject performed the tests in a stationary position, without lifting off the saddle, with his feet strapped onto the pedals. Each player performed five 10-second maximal cycloergometer tests with increas-
ABSTRACTPurpose. The aim of the study was to follow the changes of maximal power output and power-velocity relationship in male volleyball players during an annual training cycle. Basic procedures. The study was conducted on six first-league volleyball players: age 25.0 ± 5.3 years, body height 195.2 ± 7.2 cm and body mass 91.2 ± 14.7 kg. Force-velocity and power-velocity relations were determined from five maximal cycle ergometer exercise tests, 10 s each, with increasing external loads amounting to 2.5, 5.0, 7.5, 10.0 and 12.5% of body weight, respectively. There were 2-min breaks between the tests. Maximal power output was computed from power-velocity curves. Maximal power output and power-velocity relationships were determined before the preparatory period (I), after the first competitive season (II) and after the second competitive season (III). Main findings. Significant increases occurred in the maximal power output from 12.80 ± 0.79 (preparatory period) to ...