University of Wisconsin-La Crosse, La Crosse, WI 54601. Tod is with the Dept of Sport and Exercise. Science, University of Wales, Aberystwyth, Aberystwyth, ...
International Journal of Sports Physiology and Performance, 2007;2:34-45 © 2007 Human Kinetics, Inc.
Monitoring Different Types of Resistance Training Using Session Rating of Perceived Exertion Favil Singh, Carl Foster, David Tod, and Michael R. McGuigan Purpose: To evaluate the effectiveness of session rating of perceived exertion (RPE) to measure effort during different types of resistance training. Method: Fifteen male subjects (age 26.7 ± 4.3 years) performed 3 protocols. All protocols consisted of same 5 exercises but with different intensities, rest periods, and numbers of repetitions. One-repetition maximum (1-RM) was defined as the maximal amount of weight that an individual could lift 1 time without support. The strength protocol included 3 sets of 5 repetitions at 90% of 1-RM with 3 minutes rest between. The hypertrophy session included 3 sets of 10 repetitions at 70% with 1 minute of rest, and the power session included 3 sets of 5 repetitions at 50% with 3 minutes of rest. Session RPE is a modification of the standard RPE scale. Session and standard RPE were measured after the completion of each set and 30 minutes postexercise, respectively. Results: Results showed a difference between both the 2 RPE values of the strength and hypertrophy protocols (P ≤ .05) but no difference between mean and session RPE values for the power protocol. During the familiarization session, session RPE was measured at 5-minute intervals for 30 minutes postexercise. There was a significant difference (P ≤ .05) between the mean RPE values at the fifth and tenth minutes postexercise when compared with 30 minutes postexercise. All other session RPE values showed no significant difference. Conclusion: The session RPE method appears to be effective in monitoring different types of resistance training, and session RPE after 30 minutes was a better indicator of the overall resistance sessions than average RPE. Key Words: RPE, hypertrophy, power
Resistance training is a well-established mode of exercise conditioning for many different populations wishing to increase physical fitness and the primary method for increasing muscle strength, power, and hypertrophy.1-3 Resistancetraining protocols designed to increase strength, power, or hypertrophy differ in
Singh and McGuigan are with the School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Joondalup, WA 6027, Australia. Foster is with the Dept of Exercise and Sports Science, University of Wisconsin-La Crosse, La Crosse, WI 54601. Tod is with the Dept of Sport and Exercise Science, University of Wales, Aberystwyth, Aberystwyth, Wales, UK SY23 2AX. 34
Session RPE and Resistance Exercise
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their organization relative to variables such as intensity, number of repetitions, total work, and rest intervals.1,4-6 One problem facing strength athletes, coaches, and researchers is how to monitor the intensity of different modes and phases of resistance training. Unlike aerobic exercise, there is no universally accepted method of monitoring resistance-training exertion.7 The rating of perceived exertion (RPE) has been investigated as a marker of exercise intensity and has been shown to correlate well with intensity of effort.3,7-12 RPE is defined by the intensity of discomfort or fatigue felt at a particular moment.12-14 Session RPE is a modification of the standard RPE scale, developed by Foster et al,15 that is used to rate the perceived exertion of the entire workout. The session RPE scale is an easy, simple, and effective method of quantifying a workout session. The session RPE scale has been shown to be a reliable and valid method of quantifying aerobic-exercise intensities16 and has been used to rate the perception of effort of individuals during a resistance-exercise session.7,10,17,18 Studies have found a higher average RPE for high-intensity exercises performed with a lower number of repetitions and a lower average rating for lower-intensity exercises performed with a high number of repetition.10,17 These studies have found RPE averaged across the workout to be comparable to the session RPE.10,17 It is known that monitoring exercise-training load and exertion during resistance training is vital for a successful periodized exercise plan.1,10 Before a successful periodized plan with different exercise protocols can be developed, a measurement of exertion is required. Different types of resistance-training exercises and training approaches induce different responses from the muscles and neurological system,2,19 so it is critical that these differences be measured appropriately. This study examined the use of session RPE after different types of resistance-training programs. This would benefit athletes and coaches by providing a reliable method of assessing and monitoring different types of resistance-training workouts in their periodized plan. The session RPE method provided after each session would allow coaches to assess the perceived exertion levels for each athlete. Furthermore, coaches can always follow up on the previous data collected to look for signs of fatigue or even overtraining. There is clearly a need for a valid and reliable method of monitoring the different types of resistance-training exercises. Accordingly, the purpose of this study was to evaluate the effectiveness of using the session RPE scale to measure effort during different types of resistance-training protocols and to examine the validity of this scale in rating different types of resistance-training sessions. A secondary purpose was to track the session RPE after the exercise sessions to learn whether there were changes up to 30 minutes postexercise.
Methods Subjects Fifteen male subjects were recruited for the study. They all had at least 1 year of resistance-training experience and were familiar with the squat and bench-press exercises. All subjects were required to refrain from other resistance-training sessions during the course of the study. All subjects provided informed consent before participation, and the protocol had been approved by the university human subjects ethics committee. Table 1 displays the subjectsʼ characteristics.
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Design A randomized, crossover experimental design was used, with each subject performing 3 different whole-body workouts requiring approximately 60 minutes. Strength-, power-, and hypertrophy-training sessions took place on separate days, performed at least 48 hours apart. Subjects completed a familiarization session before data collection. This session included instructions on how to use the category-ratio-10 (CR-10) RPE scale (Table 2), demonstration of all 5 resistance-training exercises (bench press, squats, bench pull, shoulder press, leg extension), and the measurement of each individualʼs 1-repetition maximum (1-RM). Session RPE was also recorded at 5-minute time intervals for 30 minutes after the 1-RM testing. Each 1-RM was determined using previously described methods.3,20
Methodology The following procedure for determining the 1-RM was the same for all 5 exercises. Multiple warm-up trials were performed before 1-RM testing (percentages are given of subjectsʼ estimated 1-RM), 10 repetitions at 30% followed by 2 minutes rest, 7 repetitions at 50% followed by 2 minutes rest, 4 repetitions at 70% followed by 3 min rest, 1 repetition at 90% followed by 3 minutes rest. From the last warm-up set, the loading was increased based on subject feedback so that 1-RM could be
Table 1
Subject Physical Characteristics (mean ± SD)
Subjects (N = 15) University students
Table 2
Age (y)
Height (cm)
Body mass (kg)
Number of training years (1–15 y)
26.7 ± 4.3
177.7 ± 8.6
82.1 ± 12.9
4.7 ± 3.9
Rating of Perceived Exertion (RPE) Scale Rating
Descriptor
0 1 2 3 4 5 6 7 8 9 10
rest very, very easy easy moderate somewhat hard hard very hard
maximal
Session RPE and Resistance Exercise
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achieved within 3 additional trials. The reliability of this method of 1-RM testing in our laboratory is high (ICC = .98). Session RPE was also recorded during the familiarization session. RPE recording was started at the fifth minute after the completion of the 1-RM exercise bout and recorded at 5-minute intervals until 30 minutes postexercise. The results from 1-RM testing for the 5 different resistance exercises were then used to calculate the required exercise intensity for the 3 different training sessions. Each subject was required to perform the same 5 resistance exercises for all the 3 training sessions. The order of the sessions was randomized. In this study, the workouts were split between upper body and lower body exercises, with the multiple-joint larger-muscle-group exercises performed first. Protocols for all 3 exercises are summarized in Table 3. Strength sessions are characterized by heavy resistance with a 3-minute rest period between sets. The hypertrophy session included the same exercises done at a lighter resistance with a shorter rest period of 1 minute. The strength- and hypertrophy-training sessions were typical weight-training protocols used for strength development and to increase muscle size, respectively.2,21 The power session required each resistance exercise to be performed at a fast lifting speed, with rest periods similar to the strength workout. During all training protocols, a 6-minute rest interval was allocated between exercises. The power workout was composed of exercises done at a rapid pace to maximize muscle power.2,20 This workout was different from the standard strength workout because both strength and velocity were emphasized during lifts.2 The subjects were required to execute the concentric phase rapidly and the eccentric phase slowly. Before commencing the workloads, subjects performed a warm-up set on each resistance exercise consisting of 6 repetitions at
