Twitch Force
Measure sampled twitch peak and net impulse after baseline subtraction across explicit disjoint windows; force must already be calibrated.
Description
Twitch force can be corrected by the preceding baseline.
Twitch force can be corrected by the preceding baseline. Peak net force and integrated net impulse summarize height and time accumulation separately.
The tool returns baselineForceNewtons (baseline force newtons); peakTwitchForceNewtons (peak twitch force newtons); netTwitchImpulseNewtonMs (net twitch impulse newton ms). Input measurements and model parameters are supplied by the caller; the tool computes the stated summary rather than acquiring those measurements.
When to use Twitch Force
Use Twitch Force when you already have timesMs, forcesNewtons, baselineStartMs, baselineEndMs, twitchStartMs, twitchEndMs and want baselineForceNewtons, peakTwitchForceNewtons, netTwitchImpulseNewtonMs. This is useful for checking a supplied calculation, documenting a measurement convention, or comparing observations prepared on the same basis.
How to use Twitch Force and understand its results
- Enter timesMs, forcesNewtons, baselineStartMs, baselineEndMs, twitchStartMs, twitchEndMs using the field table below. Match the units, ordering and data boundaries described in the calculation.
- Run the tool after checking the stated bounds and matching paired observations or categories. A malformed request gives a tool error rather than a usable measurement.
- Read baselineForceNewtons, peakTwitchForceNewtons, netTwitchImpulseNewtonMs. Use the calculation and interpretation below to distinguish amounts, ratios, signs and decision flags where applicable.
- Review the supplied parameters and assumptions before using the result in a report or comparing it with another observation.
| Input field | Meaning | Value type and bounds | Requirement |
|---|---|---|---|
| timesMs | Times ms | list of number | Required |
| forcesNewtons | Forces newtons | list of number | Required |
| baselineStartMs | Baseline start ms | number | Required |
| baselineEndMs | Baseline end ms | number | Required |
| twitchStartMs | Twitch start ms | number | Required |
| twitchEndMs | Twitch end ms | number | Required |
Require disjoint nonempty baseline and twitch windows; at least two twitch samples are needed for integration. Return peak net force and signed impulse.
net force = force−baselineMean; impulse[N·ms] = trapezoidal integral(net force) The symbols refer to the supplied quantities or generated values described above; unit conversions and comparison boundaries follow the stated implementation.
{
"input": {
"timesMs": [
0,
10,
20,
30
],
"forcesNewtons": [
2,
2,
7,
3
],
"baselineStartMs": 0,
"baselineEndMs": 10,
"twitchStartMs": 20,
"twitchEndMs": 30
},
"output": {
"baselineForceNewtons": 2,
"peakTwitchForceNewtons": 5,
"netTwitchImpulseNewtonMs": 30
}
}Limitations and assumptions
Negative corrected forces and impulse are retained. The result is in newton-milliseconds, not newton-seconds.
Numerical inputs must be finite. The tool checks its declared input shape and calculation constraints; those checks do not verify the quality, calibration or representativeness of the supplied observations.
Alternative or Complementary methods
Muscle Force Quantification Tool: Fit a linear force-transducer calibration and apply it to recordings, preserving signed estimates outside calibration; no strength norms are embedded. Twitch Interpolation Voluntary Activation: Calculate paired trial voluntary activation as 100·(1−superimposed/rest potentiated twitch); negative estimates are preserved to expose model/protocol incompatibility, not clipped.
Methodological background: Digital Library of Mathematical Functions: Quadrature.1
References
-
Digital Library of Mathematical Functions: Quadrature — National Institute of Standards and Technology
Similar or alternative tools
- Muscle Force Quantification Tool
Fit a linear force-transducer calibration and apply it to recordings, preserving signed estimates outside calibration; no strength norms are embedded.
- Twitch Interpolation Voluntary Activation
Calculate paired trial voluntary activation as 100·(1−superimposed/rest potentiated twitch); negative estimates are preserved to expose model/protocol incompatibility, not clipped.