electrical currents for muscle contraction

NMES

neuromuscular electrical stimulation is the use of electrical currents to produce muscle contractions in innervated muscles

it requires an intact and functioning nervous system

what activities can it be for?

muscle strengthening

muscle education or reeducation

edema control

slow twitch vs fast twitch

typically, slow twitch fibers are activated first through physiological contraction

fast twitch are triggered first for electrical

can be overflowed

how does ES strengthen muscles?

overload principle and specificity theory

overload principle

a principle of strengthening muscle that states the greater the load placed on the muscle and the higher force contraction it produces, the more strength that muscle will gain (assuming there us not damage to the muscle)

specificity theory

to increase strength…

higher - force contractions should be used

to increase endurance…

prolonged stimulation with more lower-force contractions should be used

orthopedic conditions

ACL reconstruction

TKA

nonsurgical management of orthopedic conditions

neurological conditions

occurs via direct muscle strengthening or increased excitability of the motor neuron produced by motor level ES

functional electrical stimulation (FES)

SCI

Stroke

MS, CP, TBI

FES

application of an electrical current to produce muscle contractions applied during a functional activity

ex: stimulation of the anterior tibialis to cause DF during swing phase of gait

sports medicine/performance

contraindications

pacemaker or unstable arrythmias

parameters

pulsed biphasic waveform

Russian protocol

motor point - where the nerve is going into the muscle (center of the muscle)

pulse duration: 150 and 350 microseconds

pulse frequency: 35-50 pulses per second

on and off ratio: 1:5 with 6-10 seconds on and 50-120 seconds off (ratio is decreased as patient gets stronger) → this is to cause the muscle to contract

mvic - max voluntary isometric contraction

contraindications

what is the most appropriate position for the patient to be in?

should the patient contract the muscle w/ ES? Yes! recruitment of both fibers