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Isokinetic Robotic Device to Improve Test-Retest and Inter-Rater Reliability for Stretch Reflex Measurements in Stroke Patients with Spasticity
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The Calf Raise App shows good concurrent validity compared with a linear encoder in measuring total concentric work.

Farshad Ashnai1,2, Jakob Lindskog2, Annelie Brorsson1,3

  • 1Department of Orthopaedics, The Institute of Clinical Sciences at Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.

Knee Surgery, Sports Traumatology, Arthroscopy : Official Journal of the ESSKA
|April 21, 2024
PubMed
Summary

The Calf Raise App accurately measures total concentric work during heel raises compared to a linear encoder, but shows less validity for average height. This allows for reliable tracking of plantar flexor muscular endurance.

Keywords:
Achilles tendonankle injuriesbiomechanicsgymnasticsphysiotherapy

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Area of Science:

  • Biomechanics and Exercise Physiology
  • Sports Science and Performance Analysis
  • Clinical Biomechanics

Background:

  • Plantar flexor muscular endurance is crucial for athletic performance and rehabilitation.
  • The heel raise test is a common assessment for this.
  • Linear encoders are established tools, while smartphone apps offer accessible alternatives.

Purpose of the Study:

  • To evaluate the concurrent validity of the Calf Raise App against a linear encoder.
  • To assess the accuracy of the Calf Raise App in measuring average heel raise height and total concentric work.
  • To compare two methods for quantifying plantar flexor muscular endurance in the heel raise test.

Main Methods:

  • Fifty TeamGym athletes participated in the study.
  • Concurrent validity was assessed using intraclass correlation coefficients (ICC).
  • Measurements included average heel raise height and total concentric work.

Main Results:

  • The Calf Raise App demonstrated good to excellent concurrent validity for total concentric work (ICC: 0.89).
  • Poor to moderate concurrent validity was found for average heel raise height (ICC: 0.62).
  • Mean differences were observed between the app and linear encoder for both measures.

Conclusions:

  • The Calf Raise App is a valid tool for measuring total concentric work in the heel raise test.
  • Caution is advised when using the app for average heel raise height measurements.
  • Both instruments can be used independently for tracking changes in muscular endurance over time.