Fifteen women were selected for this experiment in the form of a randomized crossover study. Measurements were taken by leg jumps over 5 obstacles 125 cm apart. The pre-test was performed twice with a two-minute rest between each trial. Immediately after finishing the second trial, a randomly selected half of the probands performed posterior chain facilitation using a foam roller, facilitating first the left leg, then the right leg and finally spinal erectors. Rolling was performed with a sense of maximal intensity and at a high rolling speed across the full length and width of the muscle with both cranial and caudal rolling directions. Facilitation was performed on each muscle group in the distoproximal direction. Immediately following the intervention, a post-test was performed a total of 3 times, 1 minute after the intervention, 3 minutes after the intervention and 5 minutes after the intervention. The control measurement was performed the same way as the intervention, but the control group of probands rested in a resting sitting position for 4 minutes instead of foam rolling. After one week, a second measurement followed, where the original control group underwent the intervention measurement and vice versa.~The Optojump instrument (Microgate, Bolzano, Italy) was used to obtain the resistance and flight phase data. A video recording (GoPro HERO 9) was taken of the skipping procedure, from which photographs were taken over each obstacle at the moment of the greatest trunk tilt (the junction of the trochanter major and the external auditory canal exit) from the vertical axis.
An experiment elucidating the immediate effect of foam rolling of the posterior chain on reactive force performance that will represent multiple jumps over low obstacles. The measurements will be performed using the Optojump device, which will provide data on the time of foot contact with the ground and the jump height. The angles of the torso inclination to the vertical will also be measured during jumping.