EMG Median Frequency Shift

Flag an EMG median-frequency decline against a caller-selected fatigue threshold.

Description

EMG median-frequency shift compares an upstream spectral median with a baseline.

EMG median-frequency shift compares an upstream spectral median with a baseline. A negative percentage denotes a decline.^[1]

Flag an EMG median-frequency decline against a caller-selected fatigue threshold.

When to use EMG Median Frequency Shift

Use this tool to flag an EMG median-frequency decline against a caller-selected fatigue threshold.

Prepare the measured movement, timing, load or preassigned score requested. Keep protocols, units, paired measurements and caller-selected thresholds consistent.

How to use EMG Median Frequency Shift and understand its results

Prepare the measured movement, timing, load or preassigned score requested. Keep protocols, units, paired measurements and caller-selected thresholds consistent.
Enter initialMedianFrequencyHz, laterMedianFrequencyHz, minimumDropPercent using the field table and calculation rules, then run the tool.
Read frequencyShiftPercent, fatigueShiftFlag. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
initialMedianFrequencyHz	Initial median frequency hz	number	Required
laterMedianFrequencyHz	Later median frequency hz	number	Required
minimumDropPercent	Minimum drop percent	number	Required

Enter positive baseline Hz and nonnegative later Hz/drop criterion. Return signed shift and inclusive decline flag; zero criterion flags unchanged frequency.

shift%=100(later/initial−1); flag=shift≤−minimumDrop

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
frequencyShiftPercent	Frequency shift percent	number
fatigueShiftFlag	Fatigue shift flag	boolean

json

{
  "input": {
    "initialMedianFrequencyHz": 100,
    "laterMedianFrequencyHz": 80,
    "minimumDropPercent": 10
  },
  "output": {
    "frequencyShiftPercent": -19.999999999999996,
    "fatigueShiftFlag": true
  }
}

Limitations and assumptions

No EMG spectrum, electrode correction or physiological fatigue diagnosis is calculated.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.

Alternative or Complementary methods

Use EMG Antagonist Coactivation: Measure antagonist EMG amplitude relative to agonist and onset lag. For a complementary task, use Deload Trigger Screen: Flag caller-defined recovery or load conditions for a deload discussion.

References

EMG Median Frequency Shift — tool.io

Similar or alternative tools

EMG Antagonist Coactivation
Measure antagonist EMG amplitude relative to agonist and onset lag.
Deload Trigger Screen
Flag caller-defined recovery or load conditions for a deload discussion.