Method to Reduce Muscle Fatigue During Transcutaneous Neuromuscular Electrical Stimulation in Major Knee and Ankle Muscle Groups

Abstract

Our study has revealed improvements in fatigue tolerance during transcutaneous neuromuscular electrical stimulation using SDSS, a stimulation strategy that alternates activation of subcompartments of muscles. The SDSS protocol can provide greater stimulation times with less decrement in mechanical output compared with the conventional protocol.

Fatigue reduction during aggregated and distributed sequential stimulation

“…Although Fatigue Index, as defined here is a common measure used to characterize fatigue, it does not capture performance throughout fatiguing trains. To do this, Torque Peak Mean was calculated as: …”

“…This technique involves “sequential” rotation of stimulation pulses between multiple active electrodes positioned over the muscle belly (SEQ). To date, several SEQ techniques have been used and have effectively reduced fatigue in human studies . Our group has been developing a technique whereby multiple active electrodes are “aggregated” (AGGR‐SEQ) at the same site and over the same area as the single active electrode used during CONV stimulation.…”

“…Our group has been developing a technique whereby multiple active electrodes are “aggregated” (AGGR‐SEQ) at the same site and over the same area as the single active electrode used during CONV stimulation. We have described this previously as spatially distributed sequential stimulation . We have shown that AGGR‐SEQ stimulation can reduce fatigue of healthy and paralyzed plantarflexors, dorsiflexors, knee flexors, and knee extensors by activating separate motor unit populations at reduced discharge rates beneath each AGGR‐SEQ electrode …”

“…To date, several SEQ techniques have been used and have effectively reduced fatigue in human studies. [17][18][19][20][21][22][23][24][25] Our group has been developing a technique whereby multiple active electrodes are "aggregated" (AGGR-SEQ) at the same site and over the same area as the single active electrode used during CONV stimulation. We have described this previously as spatially distributed sequential stimulation.…”

Minimizing muscle fatigue through optimization of electrical stimulation parameters

“…Presently, we applied our protocol to FT and TTI, as two previously used fatigues indices in the literature. [18,20,[33][34][35][36][37] A drop of MT from its maximum (100%) to 70.7% (3 dB) was chosen since, in the control engineering literature, when the system output drops by 3 dB, its performance is considered altered. [33] This value has been used in other studies.…”