RELATIONSHIP BETWEEN RPE AND REPETITIONS AT VARIOUS PERCENTAGES OF 1 RM FOR SEVERAL LIFTING EXERCISES 1233

Abstract

Prescriptive guidelines for resistance training are usually based on having individuals perform a given number of repetitions at various percentages of 1 RM, or are based on RPE. The exact relationship between these variables remains unclear, however, especially when performing exercise for various body parts. The purpose of this study was to 1) determine the number of repetitions that could be performed at 40, 50, 60 and 70% of 1 RM for four different exercises (chest press, arm curls, pulldowns, and leg extensions) and 2) to determine the relationship between RPE and number of repetitions for each lift. Twenty middle-aged adults volunteered to participate in this study. Strength was assessed for each exercise via 1 RM testing, while relative muscular endurance was assessed by having subjects perform repetitions until exhaustion for each lift. RPE was assessed after the 10th repetition on each exercise, at each percentage. Results indicated that there was a significant difference (p<.05) in the number of repetitions performed on different exercises at similar percentages of 1 RM. Both men and women performed more repetitions on pulldowns than all other exercises at all percentages. Additionally, both genders performed more repetitions on the chest press than on the arm curls and leg extensions; there were no differences between the arm curl and legs extension exercises. RPE values, as expected, increased significantly (p<.05) across all percentages for each lift. There were differences between lifts, however, at similar percentages of 1 RM. Values were lowest for the pulldown exercise at all percentages, and were highest for the arm curls and leg extensions, respectively. The findings of this study suggest that the number of repetitions which can be performed and the associated RPE values vary between different lifts, even at similar percentages of 1 RM. Thus, the amount of weight (or percentage of 1 RM) which should be lifted should not be universally prescribed across all lifts, but rather should be tailored to the specific body part being exercised.