Abstract

BACKGROUND: Isometric maximal voluntary force (IMVF) is essential for individuals' health and physical performance. Therefore, there is a need for valid and reliable devices to assess IMVF. OBJECTIVE: To determine the validity and reliability of the Valkyria Trainer Balance (R) portable force platform in its isometric mode. METHODS: Fifty-eight physically healthy individuals (30 men and 28 women) participated in the study. A repeated measures design was used to compare the inter-day test-retest reliability of peak force. The validity of the Valkyria Trainer Balance (R) R force platform was determined by comparing the peak force with the ArtOficio (R) force platform. The analysis consisted of the intraclass correlation coefficient (ICC), standard error of measurement (SEM), and coefficient of variation (CV). A CV <= 10% and ICC >= 0.80 were considered acceptable reliability, while a <= 5% and ICC >= 0.90 were regarded as high reliability. RESULTS: CV the peak force showed high test-retest inter-day reliability (CV = 4.3% and ICC = 0.99). When comparing both force platforms, there was a 1.1% difference between the two devices. CONCLUSIONS: The results of this study demonstrate that the Valkyria Trainer Balance (R) R force platform is valid and reliable for assessing IMVF in physically healthy individuals.