Reliability and Validity of the iLOAD Application for Monitoring the Mean Set Velocity During the Back Squat and Bench Press Exercises Performed Against Different Loads. (February 2021)

• Record Type: Journal Article
• Authors: Pérez-Castilla, Alejandro; Boullosa, Daniel; García-Ramos, Amador
• Is Part Of: Journal of strength and conditioning research. Volume 35:Supplement 1(2021)
• Publication Date: 2021-02
• Subjects: linear position transducer -- resistance training -- technology -- velocity-based resistance training; Physical education and training -- Periodicals; Weight training -- Physiological aspects -- Periodicals; Physical fitness -- Periodicals; 613.7
• DOI: 10.1519/JSC.0000000000003739
• Languages: English
• ISSNs: 1064-8011

Abstract

Abstract : Abstract: Pérez-Castilla, A, Boullosa, D, and García-Ramos, A. Reliability and validity of the iLOAD application for monitoring the mean set velocity during the back squat and bench press exercises performed against different loads. J Strength Cond Res 35(2S): S57–S65, 2021—This study aimed to evaluate the reliability and validity of a smartphone application ( iLOAD ) for the monitoring of mean concentric velocity (MV) during resistance training sets. Twenty males completed 2 identical sessions consisting of one set of 10 repetitions against 4 loads (25, 40, 55, 70% of the one repetition maximum [1RM]) during the back squat and bench press exercises. The MV of the 5 initial repetitions and for the whole set were determined simultaneously with the iLOAD application and a linear velocity transducer (LVT). Two independent researchers operated the iLOAD application during the experimental sessions to evaluate the interrater agreement for the assessment of MV. An acceptable but generally lower reliability was observed for iLOAD (coefficient of variation [CV] range: 5.61–9.79%) compared to the LVT (CV range: 4.51–8.18%) at 25-40-55% of 1RM, whereas the reliability at 75% of 1RM was acceptable for the LVT during the bench press (CV range: 6.37–8.26%), but it was unacceptable for the iLOAD during both exercises (CV range: 11.3–12.8%) and for the LVT during the back squat (CV range: 11.3–17.4%). Small to moderate differences (ES range: 0.24–1.04) and very high to practically perfect correlations ( r range: 0.70–0.90) were observed between the iLOAD and the LVT. A very high agreement was observed between both raters for the recording of MV during the back squat and bench press exercises ( r ≥ 0.98). Taken together, these results suggest that the iLOAD application can be confidently used to quantify the MV of training sets during the squat and bench press exercises not performed to failure.