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PubMed1992

Validity of ratings of perceived exertion as an index of exercise intensity in swimming training.

The validity of ratings of perceived exertion (RPE), proposed by Borg (1962), as an index of exercise intensity in swimming training was discussed based on the following four experiments. Experiment I: VO2 and heart rate (HR) were measured and RPE was asked in ten female and seven male physical education students with different levels of swimming skill performing submaximal and maximal work in tethered swimming. The increases in HR and RPE with increase in %VO2max were fitted well by straight lines with high correlation coefficients of r = 0.957-0.999 and r = 0.893-0.988, respectively. RPE was increased in a linear fashion with increase in HR except for a few subjects. The correlation coefficients for linear regression for individuals were 0.862-0.987. Experiment II: Swimming velocity and HR were measured in four groups with different levels of swimming skill. The breast stroke in a 50-m pool for 5 min at three RPE ratings, i.e., very light (RPE 9), somewhat hard (RPE 13) and very hard (RPE 17) was requested of these groups. In good skilled well trained college swimmers, %HRmax was fairly higher than the RPE at the RPE 9 and RPE 13 levels but coincided with the RPE at the RPE 17 level. In skilled trained physical education students, the HR increased with a corresponding increase in RPE. But in the group with low or lower levels of swimming skill, the HR kept about the same values in spite of the increase in RPE. Experiment III: Two male and six female low skilled physical education students took the swimming training in the swimming pool for 2.0-2.5 hours a day, 6 days a week, for 2 weeks. The students also received the swimming training in the sea which lasted for 2 hours each in the morning and in the afternoon for 6 days. The same RPE test, as mentioned in Experiment II, was done before, during and after swimming training. Mean swimming velocity during and after training was slightly higher than that before training at the RPE 9 and RPE 13 levels, and was much higher at the RPE 17 level. Before training, the HR was fairly higher than the RPE at the RPE 9 and RPE 13 level. But during and after training, the HR was much closer to the RPE at the RPE 9 and RPE 13 levels. Experiment IV: Two male and three female lower skilled middle-aged swimmers performed the same RPE test as mentioned in Experiment II.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1994

[Ratings of perceived exertion in a group of children while swimming at different temperatures].

The purpose of this study was to compare the Ratings of Perceived Exertion (RPE) in children while swimming at different temperatures. Five healthy male swimmers, aged 10 to 12, swam tethered using the breast stroke at 32 degrees C, 25 degrees C and 20 degrees C water temperature in a flume, and biked at 25 degrees C air temperature in contrast with swimming. In swimming, the resistance started at 1.0 kg and increased in 1.0 kg increments up to the point of exhaustion, and in bicycling, started at 0.5 kp with 60 rpm and increased in 0.5 kp increments, respectively. The subjects swam or biked for 5 min during each period, with a rest of 10 to 20 min until they had returned to their resting HR level. The last exercise intensity was for 5 min with the maximal weight the subjects could support. The last min of VO2 and 30 sec of HR were measured during each exercise period. The subjects gave their RPE assessment at the end of each exercise. The relationships between %VO2max and HR were linear with a high correlation coefficient (r = 0.995-0.998) in both water and air. However, the slope of the %VO2max-HR line tended to shift to the right in colder water. Increased VO2 of swimming in cold water was largely attributed to shivering. The RPE increased exponentially against %VO2max in both water and air and deviated more from linearity against HR. The RPE in 25 degrees C water was lowest at all submaximal swimming. At maximal swimming, however, the RPE in the four conditions were much the same. It seemed that the RPE responded differently from HR in varying water temperatures.

Child↗

PubMed1997

Heart rate, blood lactate responses and ratings of perceived exertion to 1,000 punches and 1,000 kicks in collegiate karate practitioners.

The purpose of this study was: 1) to investigate the responses of heart rate (HR), blood lactate and ratings of perceived exertion (RPE) to 1,000 punches and 1,000 kicks in collegiate highly skilled (BB Group) and novice (WB Group) karate practitioners; and, 2) to compare RPE obtained from the subjects to RPE expected by their coaches. The mean values of HR, percent of maximal HR (% HRmax), percent of maximal HR reserve (% MHRR), blood lactate and RPE in 1,000 punches for the BB Group were 102.5 +/- 14.8 beats. min-1, 53.1 +/- 8.5%, 27.1 +/- 12.7%, 0.8 +/- 0.2 mmol.1-1 and 12.2 +/- 1.2 respectively, and for the WB Group were 116.1 +/- 17.9 beats. min-1, 58.1 +/- 7.7%, 35.2 +/- 13.3%, 1.2 +/- 0.6 mmol.1-1 and 12.8 +/- 1.2, respectively. Likewise, the mean values in 1,000 kicks for the BB Group were 127.4 +/- 12.4 beats. min-1, 66.0 +/- 8.0%, 47.0 +/- 12.5%, 1.3 +/- 0.4 mmol.1-1 and 14.2 +/- 1.2, respectively, and for the WB Group were 137.0 +/- 14.4 beats.min-1, 70.1 +/- 7.4%, 52.0 +/- 12.8%, 2.4 +/- 0.8 mmol. 1-1 and 16.3 +/- 1.5, respectively. These responses to 1,000 punches and 1,000 kicks were moderate, and the RPE for 1,000 punches in both BB and WB Groups and for 1,000 kicks in the BB Group were significantly lower than the RPE expected by their coaches.

Adult↗

PubMed2000

Effect of wearing clothes on oxygen uptake and ratings of perceived exertion while swimming.

For a comparative study between swimming in swimwear (control-sw) and swimming in clothes (clothes-sw), oxygen uptake (VO2) and ratings of perceived exertion (RPE) were measured. The subjects were six male members of a university swimming team. Three swimming strokes--the breaststroke, the front crawl stroke and the elementary backstroke--were applied. With regards to clothes-sw, swimmers wore T-shirts, sportswear (shirt and pants) over swimwear and running shoes. In both cases of control-sw and clothes-sw, the VO2 was increased exponentially with increased swimming speed. The VO2 of the subjects during the clothed tests did not exceed 1.4 times of that in the case of control-sw at swimming speeds below 0.3 m/s. As swimming speeds increased, VO2 difference in both cases increased. Consequently, VO2 in the clothed tests was equal to 1.5-1.6 times and 1.5-1.8 times of that in the swimwear tests at speeds of 0.5 and 0.7 m/s, respectively. At speeds below 0.6 m/s in clothes-sw, the breaststroke showed lower VO2 than the front crawl stroke, and the elementary backstroke showed higher VO2 than the other two swimming strokes. RPE increased linearly with %peak VO2. In addition, any RPE differences among the three swimming strokes were not shown in the control-sw tests. At an exercise intensity above 60 %peak VO2, clothed swimmers showed slightly higher RPE in the front crawl stroke compared to that in the two other swimming strokes.

Adult↗

PubMed2001

A unique method for predicting cardiorespiratory fitness using rating of perceived exertion.

The purpose of this study was to develop a simple and convenient indirect method for estimating maximal oxygen uptake (VO2max) and oxygen uptake at the anaerobic threshold (VO2AT) by using workrate and a rating of perceived exertion (RPE) during a submaximal graded cycling test (GCTsubmax). One hundred and fifty-four healthy Japanese men, aged 20 to 64 years, volunteered to participate in the study. The subjects were randomly divided into two groups, a validation (V) group (n = 100) and a cross-validation (CV) group (n = 54). The V and CV groups performed a maximal cycling test and the GCTsubmax. The GCTsubmax was conducted with documentation of three categories (overall, chest, legs) of RPE, up to a rating of 15. Prediction equations of VO2max and VO2AT were developed by multiple regression analysis using data of the V group. The mean VO2max and VO2AT of the V group were 2462 +/- 484 ml.min-1 and 1349 +/- 334 ml.min-1, respectively. Correlational analyses indicated that the workrate (W) at which the legs RPE (RPElegs) reached 15 or higher was evaluated first (WRPE legs 15) together with WRPE legs 14 both yielded the highest correlation coefficients (r) with VO2max (r = 0.781) and V O2AT (r = 0.790), respectively. The developed prediction equations of VO2max and VO2AT were VO2max (ml.min-1) = 1.19 WRPE legs 15 (kgm.min-1) - 15.84 age (yr) + 13.06 weight (kg) + 1365 (R = 0.849, SEE = 261 ml.min-1) VO2AT (ml.min-1) = 1.34 WRPE legs 14 (kgm.min-1) - 5.49 age (yr) + 665 (R = 0.816, SEE = 195 ml.min-1) Results of a cross-validation analysis indicated a similar estimation (r = 0.793 and 0.853, and SEE = 240 ml.min-1 and 183 ml.min-1) compared with the above equations developed from data of the V group. Reliability coefficients of V O2max (r = 0.891) and VO2AT (r = 0.870) respectively were significant and there was no difference in the mean value between trials 1 and 2. The "RPE method" developed for estimating cardiorespiratory fitness is not only a unique indirect method but also a valid and useful tool in various settings of exercise prescription.

Adult↗

PubMed1996

The use of ratings of perceived exertion for exercise prescription in patients receiving beta-blocker therapy.

The ratings of perceived exertion (RPE) scale has received widespread acceptance for gaining a subjective estimate of work intensity and as a means of monitoring and regulating exercise intensity across a variety of populations. The original premise for the use of the scale was its high correlation with heart rate (HR). Although individual correlations between HR and RPE in individuals on beta-blocker therapy are probably as high as in untreated individuals, there is evidence to suggest that the RPE response is mediated at a given work rate, particularly at higher absolute work rates. The variation in the RPE response appears to be mediated by the type of beta-blocker therapy administered. In the interests of safety it is necessary for the exercise specialist to develop at least a basic understanding of the mechanism and effects of beta-blocker therapy as they relate to exercise prescription. beta-Blocking drugs cause a decrease in HR and cardiac output at rest and during exercise, a decrease in myocardial contractility and a decrease in coronary and muscle blood flow. These effects can initiate premature fatigue and apprehension in the exercising patient. In the light of these responses, the RPE scale provides important information and may be used to increase the accuracy of monitoring and the prescription of exercise intensity in the cardiac population. While results regarding the use and accuracy of the scale during beta-blocker treatment are equivocal, this appears to be due mainly to variations in dosage of the drug, the mode, intensity and duration of exercise and the health status of the individuals used. Overall, the RPE scale appears to be an appropriate monitoring tool, particularly when it is used after a learning period. It is concluded that nonselective beta-blockade therapy increases RPE, particularly localised RPE. This could be attributed to a decreased blood flow and oxygen delivery to the muscle and altered glycolytic metabolism, which increases local muscle fatigue. There is no evidence to suggest a decrease in the total level of oxygen consumption at given work rates. However, as beta-blocker therapy reduces the maximal oxygen consumption (VO2max) attainable, this serves to increase the exercise intensity at all work rates. Thus, for a given absolute work rate, the RPE response is higher. However, when the work rate is expressed as a proportion of the VO2max attainable during beta-blockade, the differences in RPE are minimised or disappear. Although the evidence is not conclusive, it appears that cardioselective beta-blocker therapy does not have such profound effects on the RPE response, compared with nonselective beta-blocker therapy, when this is expressed as a proportion of VO2max. However, localised RPE tends to be higher for nonselective beta-blocker therapy. Thus, the evidence indicates that RPE can be used to estimate exercise intensity, provided the specific effects of the type of beta-blocker therapy on local and central fatigue (and local and central RPE) are taken into account. Studies which have examined the effects of an endurance training programme during beta-blocker therapy have shown that RPE are decreased at given work rates after training. This has been observed for cardioselective and nonselective beta-blocker therapy, and local and central RPE. There is also some evidence to suggest that the RPE can be used as the controlling variable to regulate the exercise response. Patients on cardioselective beta-blocker therapy produce similar exercise intensities to other cardiac patients who are not receiving beta-blocker treatment.

Adrenergic beta-Antagonists↗

PubMed2003

Use of heart rate reserve and rating of perceived exertion to prescribe exercise intensity in diabetic autonomic neuropathy.

OBJECTIVE: Individuals with diabetic autonomic neuropathy (DAN) exhibit an increased resting heart rate but depressed maximal heart rate. Thus, the purpose of this study was to examine the validity of using either percent of heart rate reserve (HRR) or a rating of perceived exertion (RPE) scale to prescribe exercise intensity in diabetic individuals both with and without DAN. RESEARCH DESIGN AND METHODS: The subjects consisted of 23 individuals with type 2 diabetes, ages 45-75 years, with (DAN; n = 13) or without (No DAN; n = 10) clinical signs of DAN, as assessed by heart rate variability using the expiration-to-inspiration ratio of the R-R interval. Peak aerobic capacity was determined using a graded protocol on a cycle ergometer, with RPE, heart rate, and VO(2) values recorded at each stage. RESULTS: The subjects were similar with the exception of depressed autonomic function in DAN subjects. Peak respiratory exchange ratio values were significantly higher (P < 0.05) in the DAN group (1.08 +/- 0.02 vs. 1.02 +/- 0.01 in No DAN subjects), although DAN subjects exhibited a significantly lower (P < 0.05) peak exercise heart rate. A similarly highly linear relationship between %HRR and percent VO(2) reserve (VO(2)R) existed for both groups (r = 0.98). A similar slightly weaker relationship (r = 0.94) was found between RPE and %VO(2)R. CONCLUSIONS: In conclusion, in diabetic individuals, %HRR provides an accurate prediction of %VO(2)R and can be used to prescribe and monitor exercise intensity, regardless of the presence of DAN. The RPE scale is also a valid, albeit slightly less accurate, method to monitor exercise intensity in diabetic individuals.

Aged↗

PubMed2002

Myoplasmic calcium regulation in myotubes from horses with recurrent exertional rhabdomyolysis.

OBJECTIVE: To determine whether alterations in myoplasmic calcium regulation can be identified in muscle cell cultures (myotubes) and intact muscle fiber bundles derived from Thoroughbreds affected with recurrent exertional rhabdomyolysis (RER). ANIMALS: 6 related Thoroughbreds with RER and 8 clinically normal (control) Thoroughbred or crossbred horses. PROCEDURES: Myotube cell cultures were grown from satellite cells obtained from muscle biopsy specimens of RER-affected and control horses. Fura-2 fluorescence was used to measure resting myoplasmic calcium concentration as well as caffeine- and 4-chloro-m-cresol (4-CMC)-induced increases in myoplasmic calcium. In addition, intact intercostal muscle fiber bundles were prepared from both types of horses, and their sensitivities to caffeine- and 4-CMC-induced contractures were determined. RESULTS: Myotubes of RER-affected and control horses had identical resting myoplasmic calcium concentrations. Myotubes from RER-affected horses had significantly higher myoplasmic calcium concentrations than myotubes from control horses following the addition of > or = 2mM caffeine; however, there was no difference in their response to 4-CMC (> or = 1 mM). Caffeine contracture thresholds for RER and control intact muscle cell bundles (2 vs 10mM, respectively) were significantly different, but 4-CMC contracture thresholds of muscle bundles from RER-affected and control horses (500 microM) did not differ. CONCLUSIONS AND CLINICAL RELEVANCE: An increase in caffeine sensitivity of muscle cells derived from a family of related RER-affected horses was detected in vitro by use of cell culture with calcium imaging and by use of fiber bundle contractility techniques. An alteration in muscle cell calcium regulation is a primary factor in the cause of this heritable myopathy.

Animals↗

PubMed2004

Effect of oral administration of dantrolene sodium on serum creatine kinase activity after exercise in horses with recurrent exertional rhabdomyolysis.

OBJECTIVE: To determine the effect of oral administration of dantrolene sodium on serum creatine kinase (CK) activity after exercise in horses with recurrent exertional rhabdomyolysis (RER). ANIMALS: 2 healthy horses and 5 Thoroughbreds with RER. PROCEDURE: 3 horses received 2 doses of dantrolene (4, 6, or 8 mg/kg, p.o., with and without withdrawal of food) 2 days apart; 90 minutes after dosing, plasma dantrolene concentration was measured spectrofluorometrically. On the basis of these results, 5 Thoroughbreds with RER from which food was withheld received dantrolene (4 mg/kg) or an inert treatment (water [20 mL]) orally 90 minutes before treadmill exercise (30 minutes, 5 d/wk) during two 3-week periods. Serum CK activity was determined 4 hours after exercise. Plasma dantrolene concentration was measured before and 90 minutes after dosing on the first and last days of dantrolene treatment and before dosing on the first day of the inert treatment period, RESULTS: 90 minutes after dosing, mean +/- SEM plasma dantrolene concentration was 0.62 +/- 0.13 and 0 microg/mL in the dantrolene and inert treatment groups, respectively. Serum CK activity was lower in dantrolene-treated horses (264 +/- 13 U/L), compared with activity in water-treated horses (1,088 +/- 264 U/L). Two horses displayed marked muscle stiffness on the inert treatment. CONCLUSIONS AND CLINICAL RELEVANCE: In 5 horses with RER from which food had been withheld, 4 mg of dantrolene/kg administered orally provided measurable, though variable, plasma concentrations and significantly decreased serum CK activity after exercise in 4 of those horses.

Administration, Oral↗

PubMed2005

Rating perceived exertion during short duration, very high intensity cycle exercise.

This study compared undifferentiated ratings of perceived exertion (RPE) during short duration, very high intensity cycle exercise using high and low resistance. 30 recreationally trained males (24.2 +/- 2.4 yr.) were memory-anchored to the Borg 15-category scale. The high and low resistance exercises were defined by 30-sec. maximum tests assigned in counterbalanced order, with resistances set before testing during an orientation session. High resistance was 10% of body mass. Low resistance resulted in the same total work as the high resistance over the 30-sec. sessions (+/-5%) but increased pedal rate. RPE was taken at 8, 13, 18, 23, and 28 sec. during the high and the low resistance exercises. Measurements were compared using a 2-way repeated-measures analysis of variance. RPE was significantly greater (p=.005) for the high than the low resistance exercise at each interval. RPE increased when the subjects were required to pedal against a greater resistance and produce the highest forces. These RPE data are consistent with data from both aerobic cycle and resistance exercise. The data suggest that instantaneous force production, not summed work, is a primary determinant of RPE. All of these observations support Cafarelli's theoretical model of effort sense. In conclusion, as an individual generates more force during high resistance exercise than in light resistance exercise, a potential explanation of our results is that the increased motor outflow and corollary sensory signal lead to a greater sense of effort.

Adult↗

PubMed2005

Effect of pedal rate and power output on rating of perceived exertion during cycle ergometry exercise.

This study examined differentiated rating of perceived exertion (RPE), heart rate, and heart-rate variability during light cycle ergometry exercise at two different pedal rates. 30 healthy men (22.6 +/- 0.9 yr.) were recruited from a student population and completed a continuous 20-min. cycle ergometry exercise protocol, consisting of a 4-min. warm-up (60 rev./min., 30 Watts), followed by four bouts of 4 min. at different combinations of pedal rate (40 or 80 rev./min.) and power output (40 or 80 Watts). The order of the four combinations was counterbalanced across participants. Heart rate was measured using a polar heart-rate monitor, and parasympathetic balance was assessed through time series analysis of heart-rate variability. Measures were compared using a 2 (pedal rate) x 2 (power output) repeated-measures analysis of variance. RPE was significantly greater (p<.05) at 80 versus 40 rev./min. at 40 W. For both power outputs heart rate was significantly increased, and the high frequency component of heart-rate variability was significantly reduced at 80 compared with 40 rev./min. These findings indicate the RPE was greater at higher than at lower pedalling rates for a light absolute power output which contrasts with previous findings based on use of higher power output. Also, pedal rate had a significant effect on heart rate and heart-rate variability at constant power output.

Adult↗

PubMed1979

Perceived exertion of professional hockey players.

18 professional hockey players were tested on the treadmill with a modified Balke procedure and also for maximum isokinetic strength with the Cybex II instrument. Immediately after each test the subject completed the Borg Scale of Perceived Exertion. The treadmill effort was perceived as being "somewhat hard work" while the maximum strength effort was considered "very light." This conflicts with previous literature. It may be that professional hockey players adapt to physical stress and do not respond perceptually to such stimuli in a typical manner.

Adult↗

PubMed1988

Influence of aerobic fitness on ratings of perceived exertion during light to moderate exercise.

Based on scores from a maximal exercise test on a bicycle ergometer, 24 college-age women were classified into three aerobic-fitness groups. Each subject then completed two randomly ordered cycle exercise bouts at 1-wk. intervals. The exercise bouts required the subjects to pedal for 24 min. attaining and then maintaining a target heart rate of either 30% or 60% of heart-rate reserve. Ratings of perceived exertion (RPE) were reported at the end of each third minute of the exercise period. Repeated-measures analysis of variance indicated the RPE was significantly related to the exercise workload and duration of exercise. No main effect was found for fitness. Two-way interactions were detected for fitness x duration of exercise and for workload x duration of exercise.

Exercise↗

PubMed1989

Relationship between ratings of perceived exertion and exercise-induced decrease in state anxiety.

24 females (aged 18 to 28 yr.) completed two 24-min., randomly ordered bicycle ergometer exercise bouts at workloads maintaining steady state at 30% and 60% heart-rate reserve. Ratings of perceived exertion (RPE) were recorded at 3-min. intervals from Minutes 9 to 24 of exercise. State anxiety was measured prior to, immediately following and 50 min, after cessation of exercise. Regression analysis indicated no relationship between RPE and the pre- to postexercise changes in state anxiety.

Adolescent↗

PubMed1991

Influence of physical exertion on mental performance with reference to training.

The aim of this study was to assess the effect of physical exertion (treadmill) on mental performance (matching a comparison design). Nine pairs of monozygotic twins (boys aged 11 to 14 yr.) were randomly divided into two groups, one trained and one untrained, while eight boys of the same age served as a control group. The trained group underwent a specifically designed program lasting six months. The trained and untrained groups performed on the treadmill for 20 min. at a running speed intensity above their individual anaerobic thresholds. Mental performance was evaluated by analysing mean number of correct answers, time taken to reach correct answers (decision time), and wrong answers. A 3 x 2 (group x pre/posttest) analysis of variance with repeated measures on the last factor yielded no significant differences; however, significant pre- versus posttest differences on correct answers and decision times occurred among the exercised groups.

Adolescent↗

PubMed1992

Is perception of exertion a unique characteristic?

This study assessed the extent to which perception of exertion (RPE), as measured by Borg's 1971 scale using bicycle ergometry, is a unique perceptual trait. Correlations run for 35 subjects between RPE and a battery of seven perceptually oriented tasks were not significant, implying that RPE may be a unique perceptual ability.

Humans↗

PubMed1994

Validity of a perceived exertion scale for children: a pilot study.

The purpose of this study was to examine the validity of a recently developed rating scale of perceived exertion, the Children's Effort Rating Table (CERT), for controlling exercise intensity in young children. 16 children (M age = 9.9 yr., SD = 1.2) performed three separate exercise tests on a mechanically braked cycle ergometer. Stage I (response protocol) consisted of a graded test with heart rate and perceived effort rating recorded in response to specified steady-state work outputs. Stage II (production protocol) examined subjects' ability to produce work outputs corresponding to levels 5, 7, and 9 of the CERT. This protocol was repeated on a further occasion (Stage III) to assess the reliability of the findings. Pearson correlations between ratings and heart rate (0.76) and ratings and work output (0.75) highlight the potential of the scale as a valid measure of exercise intensity. Also, the work rates produced by subjects in Stage II correlated 0.89 with those predicted from Stage I; however, analysis of variance showed that work output was significantly lower in Stage II than predicted. Finally, an intraclass correlation of 0.91 between Stages II and III suggests that the scale gave a reliable estimate of exercise intensity of children. The findings from this pilot study suggest that children's perceptions of effort might be used to guide intensity of exercise during structured activity classes.

Attitude↗

PubMed1994

Accuracy and reproducibility of an exercise prescription based on Ratings of Perceived Exertion for treadmill and cycle ergometer exercise.

The accuracy of regulating exercise intensity by Ratings of Perceived Exertion (RPE) was examined. Subjects underwent 4 production trials, 2 on a treadmill (P1A, P1B) and 2 on a cycle ergometer (P2A, P2B). 9 untrained subjects used only their perceptions of effort to regulate exercise intensity. Target intensity was the RPE equivalent to 60% VO2max. Exercise intensity (VO2) during P1A, P1B, and P2A did not differ from the target, but during P2B was lower than target. During P1A and P1B heart rate did not differ from the target but was lower than target during P2A and P2B. RPE seems a valid means of regulating exercise intensity during repeated bouts of treadmill exercise at 60% VO2max; however, exercise intensity during repeated bouts on the cycle ergometer may be lower than target.

Adult↗