Evaluation of multiple one repetition maximum strength trials in untrained women.

Resistance training for health is increasingly popular, yet limited research exists regarding the most appropriate and reliable methods to evaluate outcomes among nonathletic populations. The purpose of this study was to evaluate differences between multiple trials of 1 repetition maximum (1RM) strength in healthy previously untrained women (35.5 +/- 2.1 years). Nineteen participants completed 3 trials of 1RM chest and leg press with at least 24 hours rest between trials. Familiarization was incorporated into trial 1 for both tests. All trials were highly reliable (intraclass correlation = 0.95). For 1RM chest press, nonsignificant strength changes between trials 1-2 and 2-3 were 1.2 +/- 0.3 kg (p = 0.13) and 1.3 +/- 0.4 kg (p = 0.18), respectively, while the overall increase between trials 1-3 was 2.5 +/- 0.7 kg (p = 0.06). For 1RM leg press, strength changes between trials 1-2 and 2-3 were 6.9 +/- 0.6 kg (p = 0.05) and 7.3 +/- 0.4 kg (p = 0.01), respectively, while the overall difference between trials 1-3 was 14.2 +/- 1.0 kg (p < 0.01). In this study of untrained women, evaluation of maximal strength was significantly different between multiple repeated trials of lower-body strength but not upper-body strength. Thus, it was determined that a series of 3 1RM tests was sufficient to obtain a consistent measurement of maximal upper-body strength (chest press) but not lower-body strength (leg press). These findings may be of assistance for efficient reliable field testing of untrained women.