The participants performed a multi-phase warm-up and then completed 3 sets of 5 repetitions of drop jumps with a 3-minute rest period, twice a week for a total of 8 weeks.

The participants followed the same full warm-up protocol as the experimental group, with the exception of the drop jump

Three sets, each consisting of 5 repetitions with 3-minute breaks between sets, to be performed twice a week. During each DJ trial, the participants were asked to perform a maximum vertical jump with their hands at their sides as soon as possible after touching the ground. They were also given 15 seconds to climb back onto the drop and perform another trial.

Initially, the athlete stands upright on a flat surface or force platform, feet shoulder-width apart, hands on hips (to eliminate arm swing). Without a pause, the athlete performs a quick downward movement (countermovement) by bending the knees and hips, then immediately jumps vertically as high as possible. The athlete lands in an upright position on the same spot, trying to absorb the impact with knees slightly bent. Jump height and flight time is recorded using an optical system, Optojump™ system(Microgate, Bolzano, Italy) connected to a personal computer with dedicated software(OptojumpTM Next software). The system consists of two optical bars, a receiver and a transmitter, positioned 1m apart. The bars identify ground contact time(with a precision of 1ms) and then convert non-contact time into cm. Based on recommendations on optimal jump height (20 to 60cm).

Ankle stability was assessed using a functional monopodalic protocol, which involved four jumps on one foot: two per leg, both frontally and laterally. These jumps were performed by stepping over an adjustable obstacle set at 70% of the maximum height reached on a pressure platform (SensorMedica freeMed 40×40, Guidonia Montecelio, Italy). The platform has an active sensory surface of 40×40 cm with a thickness of only 8 mm and a low weight of approximately 4 kg. Inside, there are resistive sensors coated in 24K gold on conductive rubber, with a density of approximately 10,000 sensors/m².The acquisition frequency is high, up to 400 Hz, allowing for detailed dynamic analysis, and the sensors have a life cycle of over 1,000,000 cycles of use

Two cones were placed 10 meters apart. The participants were then asked to perform 3 sprints, with 3-minute recovery periods in between. A manual stopwatch was used, which was started exactly when the operator gave the start signal and stopped exactly as the subject passed the second cone.