The purpose of this study was to examine the Rear foot elevated split squat (RFESS) five repetition maximum test as a valid and reliable field method for measuring unilateral leg strength symmetry. With institutional ethical approval, 26 subjects (age = 23.8 ±4.6 years, mass = 88.1 ±10.7kg, height = 1.79±0.1m) with a minimum two years strength and conditioning experience were recruited. Following a familiarisation, session subjects performed an incremental 5 repetition maximum (RM) protocol on both legs, on two occasions where 3D motion and force data were collected. excellent reliability was found (ICC = 0.93 CL 0.88-0.96) in the load achieved between tests (mean load =0.96 ±0.18 kg/kg). Moderate reliability of bar load symmetry was found between test and re-test conditions correlation (ICC = 0.73, 0.33-0.91) with no proportional bias between sessions. Validation of the exercise was measured using a Pearson correlation between asymmetries in vertical ground reaction forces of the lead foot and bar load. When all maximal trials, from both test conditions, were analysed, a most likely large positive correlation (0.57, 0.30 to 0.76) were found for mean lead foot vGRF. When a threshold level of load symmetry (96.54% - 103.46%) was applied, a most likely large positive correlation (r = 0.59, 0.14-0.84) between symmetry in lead foot vGRF was found in subjects who exceeded this limit. Findings of this study suggest the RFESS is a valid and reliable measure of unilateral leg strength symmetry. Practitioners are recommended to use this exercise to investigate the strength symmetry of athletes, but are guided to note that a threshold level of symmetry (96.54% - 103.46%) may be required to have been exceeded to indicate a true difference in vGRF production
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CORE (COnnecting REpositories)
CORE (COnnecting REpositories)