Effect of training status on reliability of one repetition maximum testing in women

In untrained adults, multiple trials of maximal strength testing are necessary to obtain reliable measures. Training status may positively influence test-retest reliability and increase testing efficiency. The purpose of this study was to evaluate the effect of training status on differences between trials of 1 repetition maximum (1RM) measurement in women. Before (untrained women [UTW]) and after (trained women [TRW]) an 8-week resistance training program, 10 women (45.6 ± 1.4 years; body mass index 28.7 ± 1.6 kg·m) completed 3 trials of 1RM chest and leg press with at least 24 hours rest between trials. In UTW, differences between chest press trials were nonsignificant (trials 1-2: 2.36 ± 1.39 kg, p = 0.37; trials 2-3: 0.82 ± 0.77 kg, p = 0.95; trials 1-3: 3.18 ± 0.16 kg, p = 0.07), although a significant difference between leg press trials 1-3 was observed (trials 1-2: 6.55 ± 3.31 kg, p = 0.25; trials 2-3: 2.52 ± 1.1 kg, p = 0.15; trials 1-3: 9.07 ± 2.83 kg, p = 0.04). In TRW, differences between all 1RM trials were nonsignificant for both the chest press (trials 1-2: -0.65 ± 2.11 kg, p = 1.0; trials 2-3: 1.62 ± 0.69 kg, p = 0.15; trials 1-3: 0.96 ± 2.07 kg, p = 1.0) and leg press (trials 1-2: -1.51 ± 2.13 kg, p = 1.0; trials 2-3: 3.53 ± 3.0 kg, p = 0.82; trials 1-3: 2.01 ± 3.87 kg, p = 1.0). Our results suggest that training status has a positive influence on the efficiency of maximal strength measurement. For trained middle-aged women, a single trial of 1RM chest or leg press may be sufficient to obtain an accurate and reliable measure of maximal strength.