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Valid and Reliable Barbell Velocity Estimation Using an Inertial Measurement Unit
Steffen Held1, Ludwig Rappelt1, Jan-Philip Deutsch1
1Department of Intervention Research in Exercise Training, Institute of Exercise Training and Sport Informatics, German Sport University, 50933 Cologne, Germany.
International Journal of Environmental Research and Public Health
|September 10, 2021
Summary
The VmaxPro® device accurately measures mean concentric barbell velocity (MCV) during resistance training. While reliable for MCV, its displacement measurement shows less accuracy, especially for squats.
Area of Science:
- Biomechanics and Exercise Physiology
- Sports Technology and Performance Monitoring
Background:
- Accurate assessment of mean concentric barbell velocity (MCV) and displacement is vital for optimizing resistance training.
- Existing technologies for measuring these parameters vary in ease of use and accuracy.
- The VmaxPro® is an accessible inertial measurement unit designed for tracking resistance training metrics.
Purpose of the Study:
- To evaluate the validity and reliability of the VmaxPro® inertial measurement unit for assessing MCV and barbell displacement.
- To compare VmaxPro® measurements against a criterion standard (linear position transducer) in trained individuals.
Main Methods:
- Nineteen trained males performed squats and hip thrusts at 75% of their 1-repetition maximum (1RM).
- Mean concentric barbell velocity (MCV) and displacement were measured simultaneously using the VmaxPro® and a Speed4Lift® linear position transducer.
- Validity and reliability were assessed using intraclass correlation coefficients (ICCs) and limits of agreement (LoA).
Main Results:
- The VmaxPro® demonstrated good to excellent validity and reliability for MCV assessment, with minimal systematic bias and low LoA for both squat and hip thrust exercises.
- Displacement measurements showed acceptable validity for hip thrusts but a significant systematic bias and high LoA for squats.
- Reliability for MCV was good, while displacement reliability was moderate to good but with a high LoA, particularly for squats.
Conclusions:
- The VmaxPro® is a valid and reliable tool for assessing mean concentric barbell velocity (MCV) in resistance training.
- While MCV measurements are accurate, the displacement measurement's validity and reliability are exercise-dependent, showing limitations for squats.
- The device offers a practical solution for monitoring MCV, contributing to effective program design and athlete performance analysis.
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