Familiarization and Reliability of One Repetition Maximum Strength Testing in Older Women

Strength is a fundamental component of physical fitness, and therefore should be precisely assessed. The purpose of this study was to analyze the number of testing sessions required to achieve consistent 1 repetition maximum (1RM) strength measurements in untrained older women. Forty-five untrained older women were measured for 1RM in bench press machine (BP), leg extension (LE) machine, and free weight arm curl (AC). Reliability coefficients for trials 1 and 2 for BP (intraclass correlation coefficient [ICC] = 0.973) and LE (ICC = 0.976) were higher than for AC (ICC = 0.953). Percent change from trial 1 to 2 for BP (3.5 ± 10.9%) and AC (3.8 ± 8.1%) was less than for LE (5.4 ± 6.2%), but all were significant increases between trials (p < 0.05). Trial differences were reduced to nonsignificant levels (p > 0.05) in the third trial for BP (0.0 ± 0.0%), LE (1.2 ± 3.0%) and AC (2.7 ± 5.9%). Reliability coefficients rose for BP and LE (ICC = 0.999) and AC (ICC = 0.963) when a third trial was performed. Bland and Altman plotting showed very small bias and limits of agreement (LoA) for both the exercises (BP: bias = 0 kg, limits of agreement = 0 kg; LE: bias = -0.16 kg, LoA = 2.21 kg; AC: bias = -0.11 kg, LoA = 1.72 kg). This approach to determine 1RM strength values produced rapid lifting technique familiarization resulting in a need of 2 to 3 test sessions to achieve consistent 1RM measurements in untrained older women.