Extended Data Fig. 7: Configurations of frequency-specific EES trains to elicit functional muscular and kinematic activity.

Step 1, Configuration of electrodes to target the hotspots associated with weight acceptance (top) and whole-leg flexion (bottom). Example from participant P3. EES bursts are delivered at 20 Hz. (weight acceptance, optimal frequency for motor neurons innervating extensor muscles) and 100 Hz (whole-leg flexion, optimal frequency for motor neurons innervating flexor muscles) to elicit muscle responses, recorded from the Iliopsoas (Il), Rectus Femoris (RF), Vastus Lateralis (VLat), Semitendinosus (ST), Tibialis Anterior (TA), Gastrocnemius Medialis (MG), and Soleus (Sol) muscles (mean response, n = 5 repetitions). The muscles associated with the targeted hotspot are color-coded. Polar plots report the normalized muscle responses, using the same convention as in Extended Data Figure 7. Polar plot units are normalized with respect to the baseline (n-fold). Bar plots report the amplitude of associated kinematic responses from each joint, and the selectivity indexes for targeted and non-targeted muscles (n = 5 repetitions for each stimulation configuration). Step 2, Similar representations are shown for participant P1.