Table 1 Explanation of the assessed motor unit parameters
Measure | Calculation | Conversion-Units | Assessment |
|---|---|---|---|
Individual Motor Unit Measures | |||
SMUP area | Surface motor unit potential area | uV*msec | Motor unit size |
mFR | Mean firing rate | /sec | Motor unit mean firing rate |
Estimates of motor unit relationship to muscle activation | |||
MUmV | (SMUP area)*FR | 0.001* uV | Motor unit mean contribution to contraction |
MURI | SEMG/1000*MUmV | Relative index of number of active units in field of measurement during contraction | |
Estimate of overall muscle characteristics per unit force | |||
(SMUP area)/N | Surface motor unit potential area per Newton force generated | uV*msec/N | Mean motor unit size per Newton force generated during a contraction |
mFR/N | Mean firing rate per Newton force | 1/sec*N | Mean motor unit firing rate per Newton force generated during a contraction |
MUmV/N | (SMUP area)*mFR/N | uV/N | Mean motor unit contribution per Newton force |
MURI/N | MURI/N | 1000/N | Relative index of number of active units per unit force |