Measurement Agreement Between Samozino’s Method and Force Plate Force-Velocity Profiles During Barbell and Hexbar Countermovement Jumps

Abstract: This study aimed to measure agreement between using Samozino’s method and force plates to determine mean force, velocity and power during unloaded and loaded barbell and hexbar countermovement jumps. Twenty-one subjects performed countermovement jumps against incremental loads using both loading conditions. Ground reaction force was recorded using a dual-force plate system (1000Hz) and used as the criterion method to compare to Samozino’s method. Reliability and validity was determined by intraclass correlation coefficients (ICC), coefficient of variation (CV), limits of agreement plots and least products regression analysis. Samozino’s method provided acceptable levels of reliability for mean force, velocity and power (ICC > 0.90, CV% < 5.5) across both loading conditions. Limits of agreement analysis showed the mean bias was 2.7%, 15.4%, 7.2% and 1.8%, 12.4%, 5.0% for mean force, velocity and power during barbell and hexbar countermovement jumps respectively. Based upon these findings, Samozino’s method is reliable when measuring mean force, velocity and power during loaded and unloaded barbell and hexbar countermovement jumps, but also identifies limitations regarding concurrent validity compared to the gold standard. Across loading conditions, Samozino’s method overestimated mean force (0.5-4.5%) and underestimated mean velocity (11.81-16.78%) and mean power (2.26%-7.85%) compared to the force plates. Due to fixed and proportional bias between criterion and predictor, the results do not support the use of Samozino’s method to measure mean force, velocity and power. Therefore, it is not recommended for practitioners to use Samozino’s method to estimate mechanical variables during loaded and unloaded countermovement jump actions using a barbell and hexbar.

Read the rest of the article using the link below.

Hicks D, Drummond C, and Williams KJ. Measurement Agreement Between Samozino’s Method and Force Plate Force-Velocity Profiles During Barbell and Hexbar Countermovement Jumps. Journal of Strength & Conditioning Research 36: 3290-3300, 2021.

Share this content: