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Countermovement Jump Analysis Using Different Portable Devices: Implications for Field Testing.

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Summary
This summary is machine-generated.

Portable devices for countermovement jump (CMJ) analysis show varying accuracy. Myotest excels in temporal measures, while Ergojump, Optojump, and MyJump are better for flight time and jump height, with Optojump being most precise.

Keywords:
force platformmeasurementsmotion analysisneuromuscular assessmentreliabilityvalidity

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Area of Science:

  • Biomechanics
  • Sports Science
  • Human Movement Analysis

Background:

  • Portable devices offer accessible methods for assessing neuromuscular parameters.
  • Countermovement jump (CMJ) is a key indicator of lower-body explosive power.
  • Validating portable devices against gold standards is crucial for reliable performance monitoring.

Purpose of the Study:

  • To evaluate the concurrent validity, test-retest reliability, and change detection capacity of four portable CMJ devices.
  • To compare accelerometric (Myotest), jump mat (Ergojump), optical (Optojump), and smartphone app (MyJump) devices against gold-standard measures.

Main Methods:

  • Concurrent validity assessed against motion-capture and force platforms.
  • Test-retest reliability evaluated using intraclass correlation coefficient (ICC) and coefficient of variation (CV).
  • Capacity to detect changes analyzed using standard error of measurement (SEM) relative to smallest worthwhile change (SWC).

Main Results:

  • Myotest demonstrated moderate-to-large associations and good reliability for contraction time and eccentric duration.
  • Ergojump, Optojump, and MyJump showed moderate-to-strong associations and good reliability for flight time and jump height.
  • All devices underestimated jump height; Optojump was the most accurate for flight time and jump height.

Conclusions:

  • Myotest is recommended for temporal ground contact parameters.
  • Ergojump, Optojump, and MyJump are suitable for flight time and jump height, with Optojump being the preferred choice.
  • Most CMJ variables reliably detect changes, except for rate of force and power development.