Skip to main content

Table 3 Comparison of main features of lower limb fatigue resistant strategies

From: Advances in selective activation of muscles for non-invasive motor neuroprostheses

Fatigue strategy Muscle fatigue definition Fatigue metric Muscle group Stimulation strategies & electrodes Subjects Results
Popovic et al. 2009 [63] 70 % decrease of max torque Fatigue Interval Quadriceps Synchronous single electrode vs Asynchronous 4 smaller electrodes 6 complete SCI patients 150 % increase of fatigue interval with electrode array
Malesevic et al. 2010 [58] 70 % decrease of max torque Fatigue Interval Quadriceps Synchronous single electrode vs Asynchronous 4 smaller electrodes 6 complete SCI patients Synchronous: 31 % increase of post-therapy muscle fatigue resistance.
20 daily sessions Asynchronous: 4 % increase of post-therapy muscle fatigue resistance.
Nguyen et al. 2011 [64] Torque decrease of 3 dB Fatigue Index, Fatigue Time, Torque-Time-Interval Tricep Surae Synchronous single electrode vs Asynchronous 4 smaller electrodes 1 complete SCI Asynchronous stimulation: higher torque values for a longer period of time
Sayenko et al. 2013 [67] Torque decrease of 3 dB Fatigue Index Knee flexors/extensors, plantar flexor/dorsiflexor Synchronous single electrode vs Asynchronous 4 smaller electrodes 15 able-bodied subjects Asynchronous stimulation higher fatigue resistant than synchronous
Sayenko et al. 2014 [65] They studied muscle contraction properties Torque-Rise Time, Rate of torque development, Half-Relaxation-Time, Rate of torque relaxation Tricep Surae, right gastrocnemius Synchronous single electrode vs Asynchronous 4 smaller electrodes 15 able-bodied subjects Amplitude of M-waves depends on the location of the stimulated pad electrodes. Peaks on M-waves on ascending phase of synchronous stimulation are fused as fatigue occurs.