Construct validity of a modification of the flexed arm hang test

Despite the ubiquitous use of the flexed arm hang (FAH) as a field test of muscular fitness, evidence for the construct validity of it is lacking. The strongest validity coefficients (r) to date are 0.71 and 0.72 found by correlating modified versions of the FAH (i.e., 90 and 180° of elbow extension, respectively) with relative dynamic strength (i.e., 1 repetition maximum [1RM] lat pull downs × body mass). Considering a significant portion of all FAH and modified flexed arm hang (MFAH) performances are isometric, the test may be more correlated with the construct of relative isometric strength (RIS) rather than relative dynamic strength. The purpose of this study was to determine if the construct validity of the 90° MFAH might be strengthened by correlating it with either absolute isometric strength (AIS) (i.e., maximum volitional isometric contraction [MVIC]) or RIS (i.e., MVIC × body mass). Thirty-one college-aged women participated in the study. Inter-rater reliability coefficients for two 90° MFAH tests were determined using intraclass correlation coefficient (ICC): F1,30 = 1.356, ICC = 0.99; F1,30 = 0.675, ICC = 0.99. In addition, test-retest reliability was also found to be excellent: F1,30 = 3.809; ICC = 0.98. Pearson product moment correlation (r) was used at an adjusted alpha level of 0.025 to examine construct validity of the 90° MFAH with both AIS (MVIC) and RIS (MVIC × body mass). Results indicated no significant relationship with AIS (r = 0.096, p = 0.606); however, a strong significant relationship emerged with RIS (r = 0.878, p = 0.000). It was concluded that 90° MFAH scores alone were not related to absolute strength; however, they were found to be a valid and reliable estimate of the construct of RIS.