Table 1

Relationship between player position, sex and jump frequency in training

	Boys				Girls
	N	Mean	Range		N	Mean	Range
Diagonal	6	26.8	11.7	45.5	1	14.2	–	–
Outside hitter	5	23.2	10.2	36.8	8	13.9	2.9	20.9
Libero	4	14.5	5.7	29.2	3	13.7	9.7	16.8
Middle blocker	8	45.9	28.3	91.0	2	12.3	11.5	13.2
Setter	3	63.9	20.3	128.2	4	13.7	10.5	21.5
Total	26	35.7			18	13.7

Jump frequency is expressed as the number of jumps per hour of training.