DOI: 10.5061/dryad.612jm64f3
title: Feats of supercontractile strength: Functional convergence of supercontracting muscle properties among hyoid musculature in chameleons

description: The structure of sarcomeres imposes limits to the capacity of striated
 muscle to change length and produce force, with z-disc and myosin filament
 interactions constraining shortening. Conversely, supercontracting
 muscles, hitherto only known among vertebrates in the tongue retractor
 muscle (m. hyoglossus) of chameleons, have perforated z-discs that allow
 myosin filaments to extend through them into adjacent sarcomeres,
 permitting continued shortening and force development. Additional
 hyolingual muscles in chameleons undergo extreme length changes during
 feeding as well and may benefit from supercontractile properties. We
 compared length-tension relationship data and transmission electron
 microscopy (TEM) images from four chameleon muscles to test for the
 presence of additional supercontracting muscle. We document the second
 known example of a supercontracting muscle among vertebrates (the m.
 sternohyoideus superficialis) and show that the m. sternohyoideus
 profundus exhibits functional convergence with supercontracting muscles by
 increasing the range of muscle lengths over which it can exert force
 through the exploitation of sarcomere length non-uniformity across its
 muscle fibers. Additionally, we show that chameleon supercontracting
 muscles may share common contractile and structural properties due to a
 common origin from occipital somites. These results provide important
 insights into the developmental and evolutionary patterns associated with
 supercontracting muscle and extreme muscle elongation.
description: # Feats of supercontractile strength: Functional convergence of
 supercontracting muscle properties among hyoid musculature in chameleons
 [https://doi.org/10.5061/dryad.612jm64f3](https://doi.org/10.5061/dryad.612jm64f3) ## Description of the data and file structure This dataset contains the data and code required to replicate analyses in (Schneider et al. 2025 - *Proc. R. Soc. B*). This dataset includes *in vitro* muscle contractile physiology data, consisting specifically of length-tension relationship data, for four chameleon muscles collected in an effort to identify supercontracting muscles. ### Files and variables #### File: CcalypA08\_-\_MH\_Data.xlsx **Description:** This file contains contractile data for the m. hyoglossus muscle from individual "CcalypA08". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypH02\_-\_MH\_Data.xlsx **Description:** This file contains contractile data for the m. hyoglossus muscle from individual "CcalypH02". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypH02\_-\_MSS\_Data.xlsx **Description:** This file contains contractile data for the m. sternohyoideus superficialis muscle from individual "CcalypH02". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypH09\_-\_MH\_Data.xlsx **Description:** This file contains contractile data for the m. hyoglossus muscle from individual "CcalypH09". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypH09\_-\_MSP\_Data.xlsx **Description:** This file contains contractile data for the m. sternohyoideus profundus muscle from individual "CcalypH09". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypH12\_-\_MSP\_Data.xlsx **Description:** This file contains contractile data for the m. sternohyoideus profundus muscle from individual "CcalypH12". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypJ04\_-\_MTS\_Data.xlsx **Description:** This file contains contractile data for the m. triceps scapularis muscle from individual "CcalypJ04". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypJ04\_-\_MH\_Data.xlsx **Description:** This file contains contractile data for the m. hyoglossus muscle from individual "CcalypJ04". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypH06\_-\_MSS\_Data.xlsx **Description:** This file contains contractile data for the m. sternohyoideus superficialis muscle from individual "CcalypH06". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypJ07\_-\_MTS\_Data.xlsx **Description:** This file contains contractile data for the m. triceps scapularis muscle from individual "CcalypJ07". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypJ09\_-\_MTS\_Data.xlsx **Description:** This file contains contractile data for the m. triceps scapularis muscle from individual "CcalypJ09". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypM05\_-\_MTS\_Data.xlsx **Description:** This file contains contractile data for the m. triceps scapularis muscle from individual "CcalypM05". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypM05\_-\_MSS\_Data.xlsx **Description:** This file contains contractile data for the m. sternohyoideus superficialis muscle from individual "CcalypM05". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypM07\_-\_MTS\_Data.xlsx **Description:** This file contains contractile data for the m. triceps scapularis muscle from individual "CcalypM07". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypJ08\_-\_MTS\_Data.xlsx **Description:** This file contains contractile data for the m. triceps scapularis muscle from individual "CcalypJ08". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypH08\_-\_MH\_Data.xlsx **Description:** This file contains contractile data for the m. hyoglossus muscle from individual "CcalypH08". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypH06\_-\_MH\_Data.xlsx **Description:** This file contains contractile data for the m. hyoglossus muscle from individual "CcalypH06". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypM08\_-\_MSS\_Data.xlsx **Description:** This file contains contractile data for the m. sternohyoideus superficialis muscle from individual "CcalypM08". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypJ05\_-\_MH\_Data.xlsx **Description:** This file contains contractile data for the m. hyoglossus muscle from individual "CcalypJ05". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypM08\_-\_MTS\_Data.xlsx **Description:** This file contains contractile data for the m. triceps scapularis muscle from individual "CcalypM08". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypH08\_-\_MSS\_Data.xlsx **Description:** This file contains contractile data for the m. sternohyoideus superficialis muscle from individual "CcalypH08". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: Supercontracting\_Muscle\_Data.csv **Description:** Compiled data from all individuals for statistical analysis. Input file for R Markdown file. ##### Variables * Individual: Individual name ID. * Muscle: Muscle name ID (HG = m. hyoglossus; MSS = m. sternohyoideus superficialis; MSP = m. sternohyoideus profundus; TS = m. triceps scapularis). * L20: The normalized muscle length at which passive force reaches 20% of peak tetanic tension (P0). * F80Low: The normalized muscle length at which active force reaches 80% of peak tetanic tension (P0) on the ascending limb of the length-tension relationship. * F80High: The normalized muscle length at which active force reaches 80% of peak tetanic tension (P0) on the descending limb of the length-tension relationship. * F80: The normalized muscle length breath over which active force is maintained over 80% of peak tetanic tension (P0), calculated as "F80High" - "F80Low". #### File: CcalypJ05\_-\_MTS\_Data.xlsx **Description:** This file contains contractile data for the m. triceps scapularis muscle from individual "CcalypJ05". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypJ08\_-\_MH\_Data.xlsx **Description:** This file contains contractile data for the m. hyoglossus muscle from individual "CcalypJ08". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypM06\_-\_MSP\_Data.xlsx **Description:** This file contains contractile data for the m. sternohyoideus profundus muscle from individual "CcalypM06". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. #### File: CcalypM07\_-\_MSP\_Data.xlsx **Description:** This file contains contractile data for the m. sternohyoideus profundus muscle from individual "CcalypM07". ##### Variables * Muscle Length (mm): The length of the muscle (in mm) at the length of maximal active force (L0). * Muscle Mass (g): The mass of the muscle (in grams). * LT Length: Length measurements for muscle contractions based on muscle lever position. * LT Finit: The initial force (in N) exerted on the muscle lever prior to stimulation. * LT Ffinal: The peak force (in N) exerted on the muscle lever following stimulation. * LT Factive: The active force of the muscle, calculated as "LT Ffinal" - "LT Finit". * LT Length_Corrected: Muscle length measurements for muscle contractions where "LT Length" at L0 is replaced with "Muscle Length (mm)" value and remaining "LT Length" measurements are adjusted based on deviation from that length. * LT Finit_Zeroed: "LT Finit" values with the minimum "LT Finit" value subtracted. * LT Ffinal_Zeroed: "LT Ffinal" values with the minimum "LT Finit" value subtracted. * LT Factive_Zeroed: "LT Factive" values with the minimum "LT Finit" value subtracted. * LT Length_Normalized: Normalized length measurements with all "LT Length_Corrected" values divided by the "LT Length_Corrected" length at L0. * LT Finit_Normalized: Normalized force measurements with all "LT Finit_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Ffinal_Normalized: Normalized force measurements with all "LT Ffinal_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * LT Factive_Normalized: Normalized force measurements with all "LT Factive_Zeroed" values divided by the "LT Factive_Zeroed" length at L0. * Fit LT Length: Muscle length values for curves fit to "Finit_Normalized" and "Factive_Normalized" data. * Fit LT Finit: Initial muscle force values for curves fit to "Finit_Normalized" data. * Fit LT Factive: Active muscle force values for curves fit to "Factive_Normalized" data. ## Code/software This dataset was analyzed in R Studio (v. 2023.09.1+494) running R v. 4.3.1. The R Markdown file performs general linear mixed models with individual as a random effect to test for an effect of muscle on L20 and F80 values using the nlme package, and pairwise post-hoc tests for each model in the emmeans package (v. 1.8.9).