Vertical jump ability was evaluated using a one-dimensional dynamometer. Before the initiation of the
measurements, a 10 min warming up was applied. All participants performed the following laboratory test items:
a) squat jump from a static semi-squatting position with a knee angle 90ο
without using arms, b) drop jump from
stands of 10 cm, c) drop jump from stands of 20 cm, d) drop jump from stands of 30 cm and e) drop jump from
stands of 40 cm (Bobbert, Huijing, van Ingen Schenau 1987; Papadopoulos et al. 2006). Participants performed
three trials for each test and the best trial was recorded. The dynamometer was connected to an A/D
transformation card, a Pentium III computer with a math processor, and specially designed software for data
reception and processing. Three trials were carried out for each type of jump, and the best result was used (test–
retest reliability, r = .90).