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JEPonline
Multi-Joint and Single-Joint Exercise Performance and Perceived Exertion with Several Different Recoveries
Gilmar Senna1,2, Estevão Scudese2,3, Felipe Carneiro2, Juliana Torres2, Cristiano Queiroz4, Estélio Dantas1,2
1Nursing and Biosciences Post-Graduation Program, Doctorate of Federal University of State of Rio de Janeiro, Brazil, 2Biosciences Laboratory of Human Movement, Tiradentes University, Brazil, 3School of Physical Education and Sports, Federal University of Rio de Janeiro, Brazil, 4Health Center Science, Catholic of Petrópolis University, Brazil
ABSTRACT
Senna G, Scudese E, Carneiro F, Torres J, Queiroz C, Dantas E. Multi-Joint and Single-Joint Exercise Performance and Perceived Exertion with Several Different Recoveries. JEPonline 2015;18(3):91-100. The purpose of this study was to compare repetition performance and rate of perceived exertion (RPE) with different rest periods for multi-joint and single-joint exercises. Fourteen trained men (20.93 ± 2.40 yrs; 75.23 ± 9.37 kg; 176.64 ± 7.53 cm; 24.03 ± 1.62 kg·m-2) completed 8 sessions with 3 sets of 10 RM loads. Barbell bench press (BP) or machine chest fly (MCF) were alternated (one each day) with different rest periods for each day (1-min, 2-min, 3-min, or 5-min). The results indicated that the shorter rest length presented greater reductions in repetition number for the BP (1-min < 2-min < 3-min, P≤0.0001), but no differences were observed between the 3-min and the 5-min rest conditions. For MCF, significant differences were evidenced for rest periods of 1-min, 2-min, and 3-min compared to 5 -(P≤0.0001). No significant differences were found between 1-min, 2-min, and 3-min. Both exercises presented progressive declines in repetition performance over consecutive sets. Increases in RPE were evident over the course of the consecutive sets for both exercises, with significant exertion values at the lower smaller rest conditions. In conclusion, the findings indicate that both exercises presented similar patterns in repetition performance and RPE.
Key Words: Muscle Strength, Weight Lifting, Physical Fitness
INTRODUCTION
According to the American College of Sports Medicine (1), the rest interval between sets can influence the outcome of resistance training programs. The most recent position statement (1), indicates that when emphasis is placed on strength development, power or hypertrophy, a 2-min to 3-min rest period is recommended for multi-joint exercises and recoveries of 1-min to 2-min between sets seems to be sufficient for single-joint exercises. Recently, several experiments have demonstrated that different rest lengths could promote distinct repetition performance for multiple sets of multi-joint exercises or over the course of a training session (7,11-15,17-19).
However, after a rigorous search, the authors found few studies that verified the influence of rest interval length between sets for multi-joint and single-joint exercises (14,15). Of these studies, the authors have observed similar patterns over the reduction of repetition number in multi-joint and single-joint exercises, regardless of the rest length investigated. Additionally, Senna et al. (15) observed lower elevations in blood lactate concentrations caused by long intervals between sets for single-joint exercise. Further, the perceived exertion (RPE) values were significantly increased over successive sets for both the multi-joint and single-joint exercises with significantly greater values for the 1-min rest condition (14,15).
However, given the current recommendations, there is little credible evidence regarding the 2-min rest length window especially for multi-joint and single-joint exercises in regards to repetition performance (14,15). This specific length (2-min) appears to be fundamental effort to consolidate the current rest recommendation (1). In addition to the importance of adding to the current body of knowledge for future recommendations, the purpose of this study was to compare the repetition performance and RPE with 1-min, 2-min, 3-min, and 5-min rest intervals between sets for multi-joint and single-joint exercises. We hypothesized that multi-joint and single-joint exercises would reveal a similar pattern of repetitions performance output and RPE values.
METHODS
Subjects
Fourteen trained men (20.93 ± 2.40 yrs; 75.23 ± 9.37 kg; 176.64 ± 7.53 cm; 24.03 ± 1.62 kg·m-2; relative strength in BP: 1.57 ± 0.30 kg·kg-1 body mass) participated in the study. All subjects indicated that they had 1-yr experience in resistance training with a minimum of 3 times·wk-1 frequency. Also, each subject confirmed the absence of any medical condition that could influence the training program. None was using anabolic-androgenic steroids, ergogenic substances or drugs that could influence the subject’s exercise performance. In addition, the subjects were instructed to avoid regular physical activity during the study period. Before data collection, all subjects responded negatively to the PAR-Q (16). The experimental procedure was approved by the Ethics Committee of the Federal University of Rio de Janeiro. Anthropometric variables and body composition were taken to determine the subjects’ height (cm) and weight (kg) for calculation of body mass index (BMI-weight/stature²), using a digital scale, Filizola, model PL 180 (Brazil) with accuracy of 0.01 kg and a stadiometer accurate to 0.1 cm, Sanny, model ES 2020 (Brazil). All procedures followed the recommendations of the International Society for the Advancement of Kinanthropometry (6).
Ten Repetition Maximum
After two familiarization sessions (similar to the test procedures), the 10 RM load was assessed for all subjects over four non-consecutive days with a randomized design. At the first-day, the subjects performed the 10 RM test for the bench press exercise (BP). During the second visit, the subjects performed the 10 RM test on the machine chest fly (MCF). Two addition visits with similar procedures were necessary to determine the reproducibility of the 10 RM. For all testing sessions, each subject performed a maximum of three attempts for each exercise with 10 RM loads and 5 min of rest between attempts. The greatest load successfully lifted between the two testing visits was considered as the 10 RM value. Standard techniques were used for each exercise (2).
To minimize errors in data collection, the following conditions were followed: (a) standardized instructions concerning testing procedures were given to the subjects; (b) all subjects were properly instructed on the techniques for each exercise; (c) body position was held constant; (d) verbal encouragement was provided during all testing procedures; and (e) mass of all free weights and barbell were determined using a precision scale.
Experimental Procedures
Seventy-two hrs after the last 10 RM test, the subjects completed the first of eight different experimental sessions (2 sessions·wk-1). For each visit, 3 sets with 10 RM loads were performed on a random cross-over design in order to determine the exercise (BP or MCF) in combination with a given rest length (1-min, 2-min, 3-min, or 5-min) implemented for each experimental session. The warm-up before each exercise consisted of 2 sets of 12 repetitions with 40% of 10 RM loads. A recovery time of 3-min was allowed between the warm-up and the experimental procedure. The subjects were verbally encouraged to perform 3 sets until volitional exhaustion. No attempt was made to control the repetition velocity, however, the subjects were told to use a smooth, controlled movement. All visits were conducted at the same time of day in order to avoid any circadian accumulation effects. The number of repetitions and the RPE (verified by Omni Res Scale) were recorded to each set for purposes of later interpretation (4,5).
Statistical Analysis
The number of repetitions was presented by mean ± standard deviation (SD) and by the median for Omni Res Scale (RPE). An intra-class correlation coefficient was used for verify the load reproducibility between 10 RM tests and retest sessions. The ANOVA (one-way) for repeated measures was used to analyze repetitions performance data between sets and between different rest conditions for each exercise. When necessary, a Bonferroni post-hoc test was applied for pair-wise comparisons. Additionally, to determine the magnitude of the findings, Effect Sizes (ESs) were calculated for each exercise set of each rest condition. The thresholds proposed by Cohen (3) were applied to determine the magnitude of the treatment effects. The Friedman test was used to detect differences in relation to RPE between sets and rest intervals conditions. When necessary, a Dunn post-hoc was implemented for pair-wise comparisons. The level of significance was set at P<0.05. Statistical software 10.0 version was used for statistical analyze (Statsoft, Inc, Tulsa, OK, USA).
RESULTS
Excellent reproducibility for 10 RM loads was observed between test and retest in both exercises (BP, r = 0.97; MCF, r = 0.94; P<0.0001). For BP, 1-min rest protocol resulted in significant reductions for the total number of repetitions compared with the other rest conditions (2-min, 3-min, and 5-min; P0.002). Similarly, the 2-min protocol showed important decreases in total repetition number when compared with the longer 3-min and 5-min rest intervals (P<0.0001). However, no differences were identified between the 3-min and the 5-min rest conditions. For MCF, 1-min, 2-min, and 3-min of rest triggered significant reductions at the total number of repetitions compared to the longer 5-min rest condition (P<0.0001). Repetitions values per set and the total number of repetitions for both exercises for each rest protocol are presented in Table 1. Figures 1 and 2 represent the curve pattern of reductions in the number of repetitions of each set different conditions in the interval exercises multi-joint and single-joint exercises, respectively.
Table 1. Number of Repetition in Each Set and the Total Number of Repetitions with 1-Min, 2-Min, 3-Min, and 5-Min Rest Intervals. Data are means ± standard deviation.
Exercise and Rest Conditions /Set 1 /
Set 2 /
Set 3 / Total Number of Repetitions
Bench Press
1-min / 10.07 ± 0.26 / 7.00 ± 1.11*§‡ / 5.21 ± 1.12*†§‡ / 22.28 ± 1.12#§‡
2-min / 10.71 ± 1.13 / 8.07 ± 1.14* / 6.43 ± 1.22*†‡ / 25.21 ± 2.86§‡
3-min / 10.21 ± 0.57 / 9.36 ± 0.93 / 8.07 ± 0.92*† / 27.64 ± 1.86
5-min / 10.14 ± 0.36 / 9.42 ± 0.75 / 8.50 ± 0.65*† / 28.07 ± 1.31
Machine Chest Fly
1-min / 10.57 ± 0.93 / 7.35 ± 1.01*‡ / 5.86 ± 0.66 *†‡ / 23.78 ± 1.25‡
2-min / 10.28 ± 0.61 / 8.35 ± 1.27* / 6.35 ± 1.39*†‡ / 25.00 ± 2.85‡
3-min / 10.21 ± 0.69 / 8.35 ± 1.08* / 7.21 ± 1.05*†‡ / 25.78 ± 2.45‡
5-min / 10.50 ± 0.65 / 9.85 ± 0.66 / 9.50 ± 1.09* / 29.85 ± 1.95
Values are Expressed in Repetition maximum (RM). *Significant difference compared with set 1; †Significant difference compared with set 2; #Significant difference compared with 2-min; §Significant difference compared with 3-min; ‡Significant difference compared with 5-min.
Figure 1. Number of Repetitions in Each Set with Rest Intervals for Bench Press of 1-Min, 2-Min, 3-Min, and 5-Min. *Significant difference compared with Set 1; †Significant difference compared with Set 2; #Significant difference compared with 2-min (P<0.05); §Significant difference compared with 3-min (P<0.05); ‡Significant difference compared with 5-min (P<0.05).
Figure 2. Number of Repetitions in Each Set with 1-Min, 2-Min, 3-Min, and 5-Min Rest Intervals for Machine Chest Fly. *Significant difference compared with Set 1; †Significant difference compared with Set 2; #Significant difference compared with 2-min (P<0.05); §Significant difference compared with 3-min (P<0.05); ‡Significant difference compared with 5-min (P<0.05).
The effect size data presented large magnitude for repetition reduction on both exercises and rest conditions (Table 2). The magnitude of reductions was more evident over the completion of the consecutive sets for all exercises in all rest interval conditions.
Table 2. Effect Size from the Second Set of Each Exercise with the 1-Min, 2-Min, 3-Min, and 5-Min Rest Intervals.
Exercise and Rest Conditions / Set 2 / Set 3Bench Press
1-Min / 3.42 (large) / 5.02 (large)
2-Min / 1.22 (large) / 2.48 (large)
3-Min / 0.80 (large) / 1.23 (large)
5-Min / 1.98 (large) / 1.53 (large)
Machine Chest Fly
1-Min / 3.42 (large) / 5.02 (large)
2-Min / 3.15 (large) / 6.42 (large)
3-Min / 2.65 (large) / 4.29 (large)
5-Min / 0.98 (large) / 1.53 (large)
For the RPE data, significant increases were observed over the course of sets completion independently of the exercise modality. Moreover, higher values were found for the 1-min and the 2-min rest intervals starting as soon as the second set for the BP exercise (Table 2). For all other rest conditions in both exercises, significant values in RPE were evident only at last set.
Table 3. Rating of Perceived Exertion (RPE) for Each Set and Exercise for 1-Min, 3-Min, 5-Min Rest Interval (Median).
Exercise and Rest Conditions / Set 1 / Set 2 / Set 3Bench press
1-Min / 7 / 7.5* / 8*‡
2-Min / 6.5 / 7* / 8*
3-Min / 6 / 7 / 8*
5-Min / 6 / 7 / 7*
Machine Chest Fly
1-Min / 6 / 7 / 8*†‡
2-Min / 6 / 6.5 / 8*†
3-Min / 6 / 6 / 7*
5-Min / 6 / 6 / 7*
*Significant difference to set 1; †Significant difference to set 2; ‡Significant difference to 5-min rest interval.
DISCUSSION
The findings in this study indicate that with regards to multi-joint BP exercise, longer rest periods (such as 3-min and 5-min) promote better consistency and a higher number of repetitions when compared with the shorter intervals (such as the 1-min and 2-min rest periods). Also, in regards to the MCF exercise, the 1-min, 2-min, and 3-min rest intervals resulted in significant reductions in total number of repetitions compared with the 5-min rest period. As to RPE, significant increases were shown over the succession of sets independent of the exercise modality. These findings can contribute for future recommendations due to the scarce multiple rest comparisons performed between multi-joint and single-joint exercises (BP and MCF).
The American College of Sports Medicine (1) recommends a minimum of a 2-min to 3-min recovery between sets for multi-joint exercises and a minimum of 1-min to 2-min rest between sets for single-joint exercise. However, our data do not support the ACSM statement due to the very similar performance reduction pattern that we found on repetition number for both exercises modalities (multi-joint and single-joint). While ACSM recommends the 2-min rest condition when the goal is the development of strength or hypertrophy (1), the present study showed dramatic performance reductions with 2-min of recovery between sets for both exercises (multi-joint and single-joint exercise).