Contractile work and biarticular mechanisms of the triceps surae muscles facilitate net ankle mechanical work at high walking speeds

All the data are stored in a MATLAB structure format. 

Slow walk = walking at 0.7 m/s

Normal walk = walking at 1.4 m/s

walk seven = walking at 2.5 m/s

walk max = walking at 2.6 +- 0.3 m/s

all_ime_result3 = the results of the linear mixed model on all parameters.

Statistical_3 = values for all individuals.

Statistical_values_3 = Average and standard errors of all parameters.

Tables_1 = all of the tables introduced in the article.

--------------------Description of the variables-------------------- 

General instruction: 

Variables that ended with “ _avg” are the average of all gait cycles.

Variables that ended with “_avg_s” are the average of all gait stance phases.

Variables that ended with “_trials” are the all data of all gait cycles.

Sampling frequency of the motion capture is: 250 Hz

Sampling frequency of the analogue channels are: 1000 Hz

Name: name of the current trial.

Participants: the code name of the individuals participated in the study.

MTJ: the displacement of the muscle-tendon junction of the gastrocnemius medialis and the Achilles tendon.

AT_elongation: the elongation of the Achilles tendon (referenced at the AT rest length in 20 degree plantarflexion)

AT_length: The absolute values of the Achilles tendon length.

MB_length: the length of the gastrocnemius medialis muscle belly. (the length between MTJ and knee joint center).

MTU_Hawkins: the length of the muscle-tendon unit with Hawkins method (with knee and ankle angle, for more info please see D. Hawkins and M. Hull 1990).

L_GM_MTU: the length of the Achilles tendon plus MB_length.

L_GM_MTU_medial_knee: the length of the Achilles tendon plus MB_length (the length of Achilles tendon and medial knee reflective marker)

AT_strain: The strain of the Achilles tendon.

Ankle: the ankle angle.

Ankle_angle_vel: the angular velocity of the ankle.

Knee: the knee angle.

Heel: The angle between the heel marker, ankle joint center and the knee joint center.

Strain_engery: The elastic strain energy of the Achilles tendon.

E_gm_ten: the elastic strain energy of the tendon of the gastrocnemius medialis.

E_gm_belly: the energy of the gastrocnemius medialis (by using the MB_length)

E_gm_MTU: the energy of the gastrocnemius medialis (by using the L_GM_MTU)

Strain_energy_rate: the power of the tendon.

Force: the force of the Achilles tendon.

F_GM: the force of the gastrocnemius medialis (CSA=0.26% of total).

Ankle_moment: The moment generated by whole triceps surae muscles around the ankle joint.

Ankle_moemnt_norm: The moment generated by whole triceps surae muscles around the ankle joint normalized with individuals body weights.

Ankle_work: the work done by whole triceps surae muscle around the ankle joint.

Ankle_work_total: net work done by triceps surae muscle around the ankle joint.

Ankle_power: The power generated around ankle joint by by triceps surae muscle around the ankle joint.

Knee_moment_gm: the moment generated around knee joint by gastrocnemius medials.

Knee_moment_gl: the moment generated around knee joint by gastrocnemius lateralis.

Knee_power_gm: the power generated around knee joint by gastrocnemius medials.

Knee_power_gl: the power generated around knee joint by gastrocnemius medials.

EMGs: the electromyography of all investigated muscles (sol, gm, ta).

EMG_Norm: normalized electromyography of all investigated muscles (sol, gm, ta) referenced with EMG during individuals maximum voluntary contraction.

MVC_Plantar: the electromyography of all investigated muscles during plantarflexion (2 trials)

MVC_Dorsi: the electromyography of all investigated muscles during plantarflexion (2 trials)

Stance_phases: Number of frames in stance phase of all trials (sampling frequency is 250 hz).

Stance_average: the average of the number of frames in stance phase (sampling frequency is 250 hz).

Swing_phase: Number of frames in stance phase of all trials (sampling frequency is 250 Hz).

Dorsi_time_s: the time when ankle is in dorsi flexion during stance phase (seconds).

Plantar_time_s: the time when ankle is in plantarflexion during stance phase (seconds).

TO_percent: the toe off in percentage of total gait cycle.

TO: the separation of the toe off in frame numbers (sampling frequency is 250 Hz).

HS: Heel strike of the right foot in frame numbers (sampling frequency is 250 Hz).

Cycle_length: the length of total gait cycle in frame numbers (sampling frequency is 250 Hz).

Shank_len_static: the length of the shank during standing.

Shank_len_gait: the length of the shank during gait.

Lever_arm: the ankle lever-arm.

V_gm_tendon: the linear velocity of the Achilles tendon.

V_gm_belly: the linear velocity of the GM muscle belly (by using the MB_length).

V_gm_MTU: the linear velocity of the GM muscle-tendon unit (by using the L_GM_MTU).

Rest_length: the length of the Achilles tendon at 20 degree plantarflexion. 

Power_GM_MTU_joint: the power of the GM muscle-tendon unit with calculation of Biarticular equation.

Power_GM_belly_joint: the power of the GM muscle with calculation of Biarticular equation.

Power_GM_ankle: the power of GM at the ankle joint with calculation of Biarticular equation.

Power_TSM_joint: the power of the total triceps surae muscle with calculation of Biarticular equation.

Power_TSM_belly_joint: the power of the total triceps surae muscle minus the power of the Achilles tendon.

Work_GM_MTU: integral of the Power_GM_ankle over time.

Work_GL_MTU: integral of the Power_GL_ankle over time.

Work_GM_Belly: integral of the Power_GM_belly_joint over time.

Work_TSM_joint: integral of the Power_TSM_joint over time.

Work_TSM_Belly_joint: integral of the Power_TSM_belly_joint over time.

Work_GM_Knee: integral of the Knee_Power_gm over tiem.

Work_GL_Knee: integral of the Knee_power_gl over time.