Effectiveness of a 2-Week Strength Training Learning Intervention on Self-selected Weight-Training Intensity

Glass, SC, Ahmad, S, and Gabler, T. Effectiveness of a 2-week strength training learning intervention on self-selected weight-training intensity. J Strength Cond Res 34(9): 2443-2448, 2020-The purpose of this study was to determine the effectiveness of an imposed (IM) vs. self-selected (SS) 2-week strength training intervention on SS resistance training intensity. Subjects 18-40 years (SS n = 10 and IM n = 10) were provided resistance training orientation (chest press, leg press, triceps extension, bicep curl, and shoulder press). On 6 different training days, subjects completed 2 sets on each machine while blinded to the load. The SS group SS loads without any intensity or effort feedback. Load, repetitions, and ratings of perceived exertion (RPE) were recorded. The IM group was encouraged to lift to fatigue, and if they exceeded 12 repetitions, subsequent load was increased (goal-attain 70% one repetition maximum [1RM]). After training, SS and IM SS loads and repetitions for all lifts, plus 3 novel lifts (pec fly, leg extension, and shoulder raise). One repetition maximum was assessed last. Comparisons between groups were made using 2-way analysis of variance. There were significant main effects for % 1RM for the condition and day (day 1 IM = 57.2 ± 12.0%, SS = 47.2 ± 13.7% and day 6 IM = 74.7 ± 10.8%, SS = 66.2 ± 13.4%). There were significant effects across days for reps (day 1 IM = 10.8 ± 4.8, SS = 12.3 ± 4.0 and day 6 IM = 9.3 ± 3.6, SS = 10.0 ± 3.0) and RPE (day 1 = 15.4 ± 2.0 and day 6 = 16.5 ± 1.9). For both SS and IM post-training SS loads exceeded 60% 1RM. However, among the novel lifts, only the pec fly was greater than 60% 1RM (pec fly 63.0 ± 11.0%, leg extension 39.8 ± 12.5%, and shoulder raise 53.1 ± 12.8%). Two weeks of supervised resistance training resulted in both IM and SS self-selecting loads greater than 60% 1RM. There were no differences after 2-weeks of training between IM load and SS load groups.