Isometric Mid-Thigh Pull Reliability and Relationship to Deadlift 1RM

John K. De Witt, Kirk L. English, J. Brent Crowell, Kent L. Kalogera, Mark E. Guilliams, Bruce E. Nieschwitz, Andrea M. Hanson, Lori L. Ploutz-Snyder
2016 Journal of Strength and Conditioning Research  
A C C E P T E D Abstract Purpose: The purpose of this investigation was to examine the reliability of the isometric mid-thigh pull (IMTP) and the relationship between IMTP peak force and deadlift 1 repetition maximum (1RM). Methods: Nine subjects (5 m/4 f; 40.6 ± 8.0 yr; 1.72 ± 0.10 m; 75.6 ± 13.4 kg) participated in this study. IMTP and deadlift 1RM were both performed during 2 testing sessions. For IMTP, peak force and peak rate of force development (RFD) were determined, in addition to RFD
more » ... n addition to RFD at 30 ms, 50 ms, 90 ms, 150 ms, 200 ms, and 250 ms after initiation of the pull. Intraclass correlation coefficients were calculated to evaluate the reliability of IMTP measures. Pearson product-moment correlations and linear regression were used to determine associations between IMTP and deadlift 1RM. Results: IMTP peak force was reproducible both within (ICC = 0.98 and 0.97) and between sessions (ICC = 0.89) and significantly correlated with deadlift 1RM (r = 0.88, P < 0.05), but intermediate force outputs and RFD were not. Lack of associations between RFD and deadlift 1RM indicate that the ability to create explosive force may be independent of the ability to create maximal force. The strong relationship between IMTP peak force and deadlift 1RM was present regardless of which IMTP repetition across the 2 sessions was examined. Conclusions: Peak force generated during IMTP is a reliable method to assess full body maximal strength. The instructions delivered to subjects will influence RFD results. A single IMTP repetition, provided adequate familiarization and warm-up, correlates strongly with deadlift 1RM. Practitioners can use the isometric mid-thigh pull test as a method to estimate maximal deadlift strength in a quick and potentially less provocative manner than traditional 1RM testing.
doi:10.1519/jsc.0000000000001605 pmid:27548797 fatcat:srd4ze5pf5actjzpyf6wf5vnwe