Biomechanical effects of the abductor hip muscles local fatigue

SampleThirteen sedentary women (21.1 ± 2.1 years of age, 1.60 ± 0.06 m of height and 56.5 ± 14.5 kg of body mass).
Fatigue protocol
The fatigue inducing protocol consisted of performing hip abduction (concentric) and adduction (eccentric) movements at a frequency of 1 Hz, marked by a metronome, from the lateral decubitus position, resisted with a mass equivalent to 5% body weight attached to the ankle. Volunteers were instructed to perform as many movements as possible and received constant standardized verbal encouragement. Briefly, the encouragements were standardized for all subjects, as the same investigator performed it by using standardized words during whole test. The test of all volunteers was managed by the same evaluator. When the volunteer failed to repeat the movements, the maximal voluntary isometric contraction of hip abduction was immediately tested using an isokinetic dynamometer Biodex System 4®, in order to verify if there was a decrease of at least 50% in torque peak. Once fatigue observed, the volunteer was conducted to perform the tasks of squatting or drop landing, with no relevant resting period. The tasks execution order was randomized. After the first task was performed, the volunteer returned to the fatigue protocol until the fatigue condition was checked again, so that the second task was carried out.
Squatting task
Immediately after performing three unipodal squat movements, the volunteer should position the knee joint at the predetermined target angle (35o) and thus remain (as still as possible) for three seconds. This procedure was performed under three conditions, namely before the application of the fatigue protocol (pre), immediately after the induction of fatigue (post), and twenty minutes after fatigue protocol (post20).
Drop landing task
Volunteers were instructed to remain in unipodal support on a platform thirty centimeters high. As soon as authorized, they leaped forward in order to land on unipodal support over a force platform placed immediately in front of the support platform. They should position the knee joint in the predetermined target position (35o) immediately after landing, and remain as still as possible for three seconds. This procedure was repeated three times in each of the following conditions: pre fatigue, fatigue and 20 min post fatigue.
Source of dataLocal fatigue effects of the abductor hip muscles on the kinematic, postural control and joint torque during a single-leg drop landing and a squatting task.

Dataset layoutThe sampling frequency is 250 Hz and the layout of the variables follows the sequence: CoM_x, CoM_y, CoM_z, CoP_x, CoP_y, GRF_x, GRF_y, GRF_z, Knee_Ang_x, Knee_Ang_y, Knee_Ang_z, Knee_Mom_x, Knee_Mom_y, Knee_Mom_z, GRM_x, GRM_y, GRM_z, Hip_Ang_x, Hip_Ang_y, Hip_Ang_z, Hip_Mom_x, Hip_Mom_y, Hip_Mom_z, Ankle_Ang_x, Ankle_Ang_y, Ankle_Ang_z, Ankle_Mom_x, Ankle_Mom_y, Ankle_Mom_z.
AcronymsCoM - Center of Mass;CoP - Center of Pressure;GRF - Ground Reaction Force;GRM - Ground Reaction Moment;Ang - Angular Position;Mom - Moment.
Axesx - Anterior-Posterior;y - Medial-lateral;z- Vertical.