Characterization of Muscle Activity During a Surface EMG-controlled Rehabilitation Game (CONTRACTIV-1S)

Exergame

During the game session, participants will be paired in advance of the visit (an adult participant with hemiparesis paired with another adult participant with hemiparesis, or a healthy volunteer and a child with cerebral palsy paired with another child with a cerebral palsy) to allow for testing of different conditions for the electromyography-controlled rehabilitation game. The estimated duration for each participant is 1 hour and 30 minutes, including a 30-minute game session.

Participants will play the rehabilitation game under different modalities : individually, in pairs in a co-active mode, or in a competitive mode.

In individual mode, they play two different games a rythm game (following the musical tempo by alternating agonist/antagonist contractions) and a target game (the participant controls a rocket that must hit targets based on the intensity of muscle contractions and the muscle being activated....).

The game modalities will be presented in a randomized order.

calculated as the mean of the maximum values of the normalized RMS envelope of the EMG signal during each muscle contraction of the Tibialis Anterior and Lateral Gastrocnemius muscles

calculated as the mean of the maximum values of the normalized RMS envelope of the EMG signal during each muscle contraction of the Tibialis Anterior and Lateral Gastrocnemius muscles

Number of contractions performed

Total duration of muscle contractions

Duration and number of muscle contractions performed at predefined target muscle activation intensities

Area under the EMG activity curve

The intensity of co-contractions is measured as the ratio of the antagonist's EMG activity during agonist contractions while playing, relative to the EMG activity recorded during the antagonist's MVIC performed before the gaming session.

The co-contraction index between the tibialis anterior and lateral gastrocnemius muscles will be calculated as the ratio between the area of overlap under the activation curves and the total area corresponding to the activation of both muscles, expressed as a percentage :

I = (area of overlap under the curve / total area of the two muscles) × 100.

A wavelet analysis will be performed by comparing the first five contractions with the last five contractions. This analysis will allow to detect potential changes in muscle activity associated with muscular fatigue

Children's Effort Rating Table (CERT) will be used to assess the child's perceived exertion and Borg Rating of Perceived Exertion Scale will be used for adult participants.

Min 0 (not at all) et max 10 (extremely)

Visual analogue scale of satisfaction will be completed by adult participants Min 0 (not at all) et max 10 (extremely)

Game Experience Questionnaire (Flow component) completed by adult participants Five questions scored from 0 (not at all) to 4 (extremely)

Changes of frequency spectrum of the EMG signal recorded during maximal voluntary isometric contraction

Changes of force produced during maximal voluntary isometric contraction recorded using a handheld dynamometer.

Changes of Amplitude of the EMG signal recorded during maximal voluntary isometric contraction

Changes of Co-contraction index and intensity of the tibialis anterior/lateral gastrocnemius muscle pair (between the first five and the last five contractions of each game modality)

System Usability Scale (SUS) will be fulfilled by adult participants Ranging from 0 to 100.

Intrinsic Motivation Inventory (IMI) ) will be fulfilled by adult participants Min = 25 and Max = 175

Researcher-developed questionnaire will be completed by adult participants

Correlation between satisfaction (Visual analogue sclae of satisfaction from 0 to 10) and activation levels (calculated as the mean of the maximum values of the normalized RMS envelope of the EMG signal during each muscle contraction) in adult participants

Correlation between flow (Game experience questionnaire 5 question from 0 to 4) and activation levels ( calculated as the mean of the maximum values of the normalized RMS envelope of the EMG signal during each muscle contraction) in adult participants

Mesures performed by a dynamometer Analyse of Correlation between maximal voluntary isometric force of the dorsiflexor and plantar flexor muscles assessed using a handheld dynamometer in two testing positions : In the seated position, with the knee flexed at 90° and the ankle at 10° of plantar flexion (i.e., the gaming position) and in the supine position, with the knee flexed at 90° and the ankle positioned at 10° of plantar flexion (standard position).