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Test-Retest Reliability of the Digijump Machine.
J Cody Sivley1, James W Navalta1, T Scott Lyons1
1Department of Physical Education and Recreation, Western Kentucky University, Bowling Green, Kentucky, USA.
International Journal of Exercise Science
|May 17, 2016
Summary
The Digijump device shows reliable physiological measurements for repetitive jumping exercises, supporting its use in bone health research. This study confirms its stability for oxygen uptake, heart rate, and perceived exertion.
Area of Science:
- Exercise Physiology
- Biomechanics
- Bone Health Research
Background:
- Repetitive jumping is a potential exercise for improving bone health.
- Assessing the physiological response and work rate monitoring of repetitive jumping is crucial.
- The reliability of the Digijump device for physiological testing needs to be established.
Purpose of the Study:
- To determine the stability reliability of the Digijump device.
- To assess the reliability of measuring oxygen uptake (VO2), heart rate (HR), and rate of perceived exertion (RPE) using the Digijump.
- To validate the Digijump as a tool for physiological testing in repetitive jumping exercises.
Main Methods:
- 17 college-aged individuals participated in the study.
- Participants completed two 3-minute repetitive jumping sessions on the Digijump machine (120 jumps/min, 1.27 cm height) separated by at least 7 days.
- Stability reliability was calculated using intraclass correlation coefficients derived from 1-way ANOVA.
Main Results:
- Absolute VO2 showed high test-retest reliability (0.95).
- Relative VO2 (0.71), heart rate (0.89), and rate of perceived exertion (0.75) also demonstrated acceptable reliability.
- The reliability coefficients were comparable to those reported for other standard ergometers.
Conclusions:
- The Digijump device exhibits acceptable stability reliability for key physiological measures during repetitive jumping.
- These findings support the Digijump's potential as a valid tool for physiological testing in exercise and bone health studies.
- Further validation is warranted to fully establish the Digijump's utility in diverse research applications.
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