Lower Ratings Of Perceived Exertion Research Articles

LETTERS TO THE EDITOR

LETTERS TO THE EDITOR

Sex Differences in Ratings of Perceived Exertion and Muscle Pain During Eccentric Contractions

1515 Few studies have examined sex differences in ratings of perceived exertion (RPE) and muscle pain during eccentric exercise. This is problematic due to the importance of eccentric contractions to functional activities and reports of lower RPE and muscle pain during eccentric contractions compared to concentric contractions. PURPOSE: To examine sex differences in RPE and muscle pain intensity and unpleasantness during eccentric isokinetic contractions. METHODS: Men (n = 34) and women (n = 40) aged about 20 years (SD = 2.20) completed eccentric strength testing with the elbow flexors of their dominant arms to determine their 5 repetition maximum (5RM). Then they completed 3 sets of 12 eccentric repetitions at 90°/s with a preload of 16% of 5RM and 60 s rest periods in between each set. Differentiated RPE (CR-10 scale) and pain (0–100 numerical scales) were assessed immediately after strength testing and each set. RESULTS: Two-way (Sex × Set) ANOVAs indicated that RPE, F2,144 = 30.92, pp < .01, η2 = .30, pain intensity, F2,144 = 31.98, pp < .01, η2 = .31, and pain unpleasantness, F2,144 = 22.23, pp < .01, η2 = .24, increased across the sets. A main effect for Sex was observed for RPE, F1,72 = 4.29, pp = .04, η2 = .06, but this effect was absent when total work across the three sets was a covariate, F1,71 = 0.34, pp = .58, η2 < .01. No other main effects or Sex by Set interactions were observed. In addition, comparisons of the women and men with RPEs between 9 and 10 for the first, second, or third sets (ns = 28–31) did not show a significant sex difference in average percentage of peak torque produced. CONCLUSION: Lower RPE for women than men during eccentric contractions has been reported, but we did not detect such a difference. In addition, we did not observe sex differences in muscle pain during eccentric contractions, which contradicts a previous report of lower muscle pain in women than men. However, such sex-related comparisons may be affected by the method of controlling for sex differences in strength and the parameters of the eccentric contractions preformed (e.g., velocity). This investigation was supported by a NIAMS postdoctoral research fellowship (F32 AR08623-02) to Erin A. Dannecker, Ph.D.

Sex Differences in Ratings of Perceived Exertion and Muscle Pain During Eccentric Contractions

1515 Few studies have examined sex differences in ratings of perceived exertion (RPE) and muscle pain during eccentric exercise. This is problematic due to the importance of eccentric contractions to functional activities and reports of lower RPE and muscle pain during eccentric contractions compared to concentric contractions. PURPOSE: To examine sex differences in RPE and muscle pain intensity and unpleasantness during eccentric isokinetic contractions. METHODS: Men (n = 34) and women (n = 40) aged about 20 years (SD = 2.20) completed eccentric strength testing with the elbow flexors of their dominant arms to determine their 5 repetition maximum (5RM). Then they completed 3 sets of 12 eccentric repetitions at 90°/s with a preload of 16% of 5RM and 60 s rest periods in between each set. Differentiated RPE (CR-10 scale) and pain (0–100 numerical scales) were assessed immediately after strength testing and each set. RESULTS: Two-way (Sex × Set) ANOVAs indicated that RPE, F2,144 = 30.92, pp < .01, η2 = .30, pain intensity, F2,144 = 31.98, pp < .01, η2 = .31, and pain unpleasantness, F2,144 = 22.23, pp < .01, η2 = .24, increased across the sets. A main effect for Sex was observed for RPE, F1,72 = 4.29, pp = .04, η2 = .06, but this effect was absent when total work across the three sets was a covariate, F1,71 = 0.34, pp = .58, η2 < .01. No other main effects or Sex by Set interactions were observed. In addition, comparisons of the women and men with RPEs between 9 and 10 for the first, second, or third sets (ns = 28–31) did not show a significant sex difference in average percentage of peak torque produced. CONCLUSION: Lower RPE for women than men during eccentric contractions has been reported, but we did not detect such a difference. In addition, we did not observe sex differences in muscle pain during eccentric contractions, which contradicts a previous report of lower muscle pain in women than men. However, such sex-related comparisons may be affected by the method of controlling for sex differences in strength and the parameters of the eccentric contractions preformed (e.g., velocity). This investigation was supported by a NIAMS postdoctoral research fellowship (F32 AR08623-02) to Erin A. Dannecker, Ph.D.

Impact Of Music On RPE During Submaximal Treadmill Exercise

0847 The impact of music on ratings of perceived exertion (RPE) during submaximal exercise has garnered much attention. Studies have indicated that subjects exercising at submaximal intensities report lower RPE's when listening to music. PURPOSE: To determine if music perceptions (like, dislike or no music) would affect work production at two RPE's. METHODS: Six physically active (VO2max 51.2 +/− 5.7 ml/kg/min) subjects, five males and one female (age 30.3+/−6.1yr), participated in this study. Subjects performed a maximal graded treadmill test using the Modified Astrand protocol to anchor them to the Borg 15 point RPE scale and to determine HRmax and VO2max. The subjects returned to the lab on two separate occasions to complete six 5 min randomly assigned trials. Subjects selected music they liked and disliked. In three trials (like, dislike, and no music), subjects produced an RPE of 13 and in three trials an RPE of 17 was produced. The subjects were blinded to the grade and speed and had three min to adjust the intensity. After three min, the subjects performed at the same speed and grade for 2 additional min. The dependent variables included self-selected grade and speed, HR, VO2, and RER. RESULTS: At an RPE of 17, there was a trend for an increase in heart rate in the music liked (p = 0.12) and music disliked (p = 0.07) trials. (Table). However, the music conditions (like, dislike or no music) did not significantly (p>.05) affect work production or any of the variables measured. CONCLUSION: Music perceptions do not appear to impact work production during submaximal treadmill exercise at RPE 13, but remains to be determined at an RPE 17.Table

Goal orientation and ratings of perceived exertion in graded exercise testing of adolescents.

This study examined the relationship between adolescents' goal orientation in sport and their ratings of perceived exertion (RPE) during a graded exercise test. Subjects (N = 114; 56 boys) were randomly selected adolescents (ages 11 to 15 years) who were part of a 5-year longitudinal study of cardiac growth. RPE was measured during each of three submaximal stages throughout the graded exercise test and again during the maximal stage. A series of regression analyses showed that RPE for female subjects was significantly predicted by Task Orientation, Perceived Ability, and Intensity of Leisure Activity at Stage 1, Task Orientation and Perceived Ability at Stage 2, and by Intensity of Leisure Activity at Stage 3. Examination of the beta weights indicated that lower RPE for the girls was related to higher Task Orientation and lower Perceived Ability and more experience with higher Intensity of Leisure Activity. Results are discussed in light of the literature pertaining to goal orientation and ratings of perceived exertion.

Effectiveness of a Commercial Head-Neck Cooling Device

The effects of head and neck cooling (Kool-It) on selected cardiovascular, thermoregulatory and perceptual variables were studied in 10 men and 10 women tested during 30 minutes of exercise on a cycle ergometer at 60% maximum oxygen consumption (Vo2max) under control (C; 30° C) and experimental head and neck cooling (E) conditions. The data show no significant (C vs. E group) differences in postexercise core temperature measured rectally or esophageally (38.1 ± 0.02 vs. 38.2 ± 0.03 and 37.9 ± 0.04 vs. 37.9 ± 0.04° C, respectively). Systolic and diastolic blood pressure showed no change after exercise (172 ± 1 vs. 171 ± 2 and 62 ± 1 vs. 64 ± 1 mm Hg, respectively). Heart rate, oxygen consumption per unit time, rating of perceived exertion (RPE), and mean skin temperatures also showed no significant differences between conditions. Thigh and calf skin temperature (Tsk) increases were greater in women than men (p < 0.05). Sweat rate was greater for women in the E than the C condition (697 ± 71 vs. 657 ± 67 g-h−1; p < 0.05), whereas plasma volume shift was significantly greater in men during E condition (-7.8 ± 1.6 vs. +0.5 ± 2.5%; p < 0.02). Finally, a significant RPE slope by sex-by-treatment interaction (p < 0.0004) showed a lower RPE slope response to exercise for women in the C condition. The data are interpreted to refute claims regarding the benefits of neck and head cooling during exercise from the Kool-It device, although some regional Tsk sex differences were observed. Kool-It had no effect on RPE during exercise in men, but accelerated RPE increases in women.

Psychophysical and physiological comparison of squat and semi-squat lifting by young males

A comparison between semi-squat and squat techniques was made for floor to knuckle height lifting using maximum acceptable weight (MAW), ratings of perceived exertion (RPE) and heart rate. Semi-squat lifting resulted in greater MAW with lower RPE and lower heart rate compared to squat lifting. Discomfort was most commonly reported in knees/quadriceps with squat lifting. Twelve of the 13 subjects preferred the semi-squat technique. The results provide evidence that the semi-squat technique may have benefits over the squat technique for lifting a medium sized box from floor to knuckle height.

Reliability of the Rating of Perceived Exertion at Ventilatory Threshold in Children

The purpose of this study was to examine the reliability of the rating of perceived exertion (RPE), using the Borg 6-20 scale, at ventilatory threshold (VT) in children. Thirty children (19 male, 11 female) with a mean +/- SD age of 10.4 +/- 1.1 yrs performed two graded exercise tests for the assessment of VT and VO2max. RPE was recorded throughout each exercise test. There were no significant (p > 0.05) differences between the mean VO2max (50.9 +/- 6.0 vs 51.0 +/- 5.7 ml.kg-1.min-1; r = 0.95) or the mean VO2 at VT (36.2 +/- 4.4 vs 36.7 +/- 4.5 ml.kg-1.min-1; r = 0.87) between trials. The mean RPE at VT during trial 1 (12.4 +/- 2.7) was significantly higher than during trial 2 (11.4 +/- 3.3; p < 0.05). The test-retest reliability correlation for the RPE at VT was r = 0.78. The lower RPE in the second trial may have been due to a greater comfort and familiarity with the testing procedures. The reliability analysis indicates that the RPE at VT within a given child is fairly consistent from trial to trial. However, large inter-individual variability in the RPE at VT (range = 6 to 19) was noted and was not related to variations in the onset of VT. This raises some concern over the use of a given RPE value or range of RPE values in the regulation of exercise intensity for this age group. The test-retest reliability of VT and VO2max in this age group is similar to previous reports.

Prescribing water-based exercise from treadmill and arm ergometry in cardiac patients

This study investigated the appropriateness of prescribing upright water-based exercise from treadmill and arm ergometry in uncomplicated, trained patients with cardiovascular disease (CVD) who were accustomed to water-based activities. Ten male patients with established CVD (mean age 59.4 +/- 8.7 yr) underwent maximal treadmill and arm ergometry in randomized counterbalanced order (half of the patients completed the treadmill test first and the other half completed the arm ergometer test first). Electrocardiographic (ECG), rating of perceived exertion (RPE), and oxygen uptake (VO2) measurements were made during both tests. Patients performed upright water-based exercise at 60, 70, and 80% of their maximal treadmill heart rate for 6 min at each intensity in a heated pool with a water temperature of 28-30 degrees C. They also performed an easy tethered swim, defined as performing at a comfortable exercise intensity, eliciting a heart rate of 86% of the treadmill maximum. VO2 and RPE were collected for all water-based exercise. To compare the RPE and VO2 between water-based, treadmill, and arm ergometry exercise, individual regression equations were constructed between heart rate, VO2, and RPE for both treadmill and arm ergometry tests. VO2 and RPE were then compared at the same heart rates between the three exercise modes. At 60% intensity, treadmill exercise exhibited a higher VO2 than water-based and arm ergometry exercise (P less than 0.05) but similar RPE. At 70%, treadmill exercise still yielded higher VO2, but also lower RPE than (P less than 0.05) and arm ergometry exercise (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

PRESCRIBING WATER-BASED EXERCISE FROM TREADMILL AND ARM ERGOMETRY IN CARDIAC PATIENTS

This study investigated the appropriateness of prescribing upright water-based exercise from treadmill and arm ergometry in uncomplicated, trained patients with cardiovascular disease (CVD) who were accustomed to water-based activities. Ten male patients with established CVD (mean age 59.4 +/- 8.7 yr) underwent maximal treadmill and arm ergometry in randomized counterbalanced order (half of the patients completed the treadmill test first and the other half completed the arm ergometer test first). Electrocardiographic (ECG), rating of perceived exertion (RPE), and oxygen uptake (VO2) measurements were made during both tests. Patients performed upright water-based exercise at 60, 70, and 80% of their maximal treadmill heart rate for 6 min at each intensity in a heated pool with a water temperature of 28-30 degrees C. They also performed an easy tethered swim, defined as performing at a comfortable exercise intensity, eliciting a heart rate of 86% of the treadmill maximum. VO2 and RPE were collected for all water-based exercise. To compare the RPE and VO2 between water-based, treadmill, and arm ergometry exercise, individual regression equations were constructed between heart rate, VO2, and RPE for both treadmill and arm ergometry tests. VO2 and RPE were then compared at the same heart rates between the three exercise modes. At 60% intensity, treadmill exercise exhibited a higher VO2 than water-based and arm ergometry exercise (P less than 0.05) but similar RPE. At 70%, treadmill exercise still yielded higher VO2, but also lower RPE than (P less than 0.05) and arm ergometry exercise (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of training on the rating of perceived exertion at the ventilatory threshold.

The purpose of this study was to determine the effect of training on the rating of perceived exertion (RPE) at the ventilatory threshold. College students were assigned to either training (n = 17) or control (n = 10) groups. Trainers completed 18 interval training sessions (five X 5 min cycling at 90-100% VO2max) and 8 continuous training sessions (40 min running or cycling) in 6 weeks. Pre- and post-training, cardiorespiratory, metabolic, and perceptual variables were measured at the ventilatory threshold during graded exercise tests on a cycle ergometer. Ventilatory threshold was that point above which VE X VO2-1 increased abruptly relative to work rate. Post-training means of trained and control subjects were compared using analysis of covariance, with pre-training values as covariates. Following training, the adjusted means for the trained subjects were significantly greater (p less than 0.05) than for controls for VO2max (6%), and for work rate (20%), VO2 (23%), and %VO2max (13%) at the ventilatory threshold. However, adjusted means for RPE at the ventilatory threshold were not significantly different (2%). Both before and after training, exercise at the ventilatory threshold was perceived as 'somewhat hard' to 'hard' (RPE = 13-15) by both groups. The relationship between RPE and %VO2max was altered by training, with trained subjects having a lower RPE at a given %VO2max. It is concluded that RPE at the ventilatory threshold is not affected by training, despite that after training the ventilatory threshold occurs at a higher work rate and is associated with higher absolute and relative metabolic and cardiorespiratory demands.