Perceptually-regulated Exercise Test Research Articles

Peak oxygen uptake measured during a perceptually-regulated exercise test is reliable in community-based manual wheelchair users

ABSTRACTThis study compares test-retest reliability and peak exercise responses from ramp-incremented (RAMP) and maximal perceptually-regulated (PRETmax) exercise tests during arm crank exercise in individuals reliant on manual wheelchair propulsion (MWP). Ten untrained participants completed four trials over 2-weeks (two RAMP (0–40 W + 5–10 W · min−1) trials and two PRETmax. PRETmax consisted of five, 2-min stages performed at Ratings of Perceived Exertion (RPE) 11, 13, 15, 17 and 20). Participants freely changed the power output to match the required RPE. Gas exchange variables, heart rate, power output, RPE and affect were determined throughout trials. The V̇O2peak from RAMP (14.8 ± 5.5 ml · kg−1 · min−1) and PRETmax (13.9 ± 5.2 ml · kg−1 · min−1) trials were not different (P = 0.08). Measurement error was 1.7 and 2.2 ml · kg−1 · min−1 and coefficient of variation 5.9% and 8.1% for measuring V̇O2peak from RAMP and PRETmax, respectively. Affect was more positive at RPE 13 (P = 0.02), 15 (P = 0.01) and 17 (P = 0.01) during PRETmax. Findings suggest that PRETmax can be used to measure V̇O2peak in participants reliant on MWP and leads to a more positive affective response compared to RAMP.

Validity of a perceptually-regulated step test protocol for assessing cardiorespiratory fitness in healthy adults

To determine whether maximal oxygen uptake (VO2max) could be predicted accurately and reliably from a 2-step, perceptually-regulated exercise test (PRET) in healthy adults. Sixteen participants (31.7±11.3years, 3 females) completed three PRETs (separated by 24-72h) and one maximal, perceptually-regulated, graded exercise test (PRETmax) on a motorized treadmill. Oxygen uptake (VO2) and heart rate (HR) were recorded during each test. VO2 values for RPE range 9-15 were extrapolated to RPE 20 and age-predicted maximal HR (HRmax) using individual linear regression analysis to predict VO2max values compared to measured VO2max. VO2 and HR values were consistent between each of four RPE levels of the PRET. ICC values ranged between 0.76 and 0.85. Predicted VO2max from both methods were lower than measured VO2max (p<0.01). Limits of agreement (LoA) for measured (41.4±5.3mlkg-1min-1) versus predicted VO2max from each of the three PRETs using RPE20 were -1.2±15.6, -1.0±7.2 and -2.1±5.5 and for HRmax were -1.8±4.2; -2.6±4.2 and -2.4±4.4mlkg-1min-1 for PRET 1, 2 and 3, respectively. The step PRET elicited significant and reliable increases in VO2 across the four RPE levels, but under-estimated treadmill VO2max. However, there was better agreement between measured and predicted VO2max when extrapolated to HRmax. As evidence indicates the underestimation of VO2max is explained by the difference in the mode of exercise, the step PRET provides a simple and convenient test of cardiorespiratory fitness.

A Perceptually-regulated Exercise Test Predicts Peak Oxygen Uptake in Older Active Adults

A Perceptually-regulated Exercise Test Predicts Peak Oxygen Uptake in Older Active Adults

A Perceptually-regulated Exercise Test Predicts Peak Oxygen Uptake in Older Active Adults

Peak oxygen uptake (VO2peak) is reliably predicted in young and middle-aged adults using a submaximal perceptually-regulated exercise test (PRET). It is unknown whether older adults can use a PRET to accurately predict VO2peak. In this study, the validity of a treadmill-based PRET to predict VO2peak was assessed in 24 participants (65.2 ± 3.9 years, 11 males). The PRET required a change in speed or incline corresponding to ratings of perceived exertion (RPE) 9, 11, 13, and 15. Extrapolation of submaximal VO2 from the PRET to RPE endpoints 19 and 20 and age-predicted HRmax were compared with measured VO2peak. The VO2 extrapolated to both RPE19 and 20 over-predicted VO2peak (p < .001). However, extrapolating VO2 to age-predicted HRmax accurately predicted VO2peak (r = .84). Results indicate older adults can use a PRET to predict VO2peak by extrapolating VO2 from submaximal intensities to an age-predicted HRmax.

Prediction of Maximal or Peak Oxygen Uptake from Ratings of Perceived Exertion

Maximal or peak oxygen uptake (V˙O2 max and V˙O2 peak , respectively) are commonly measured during graded exercise tests (GXTs) to assess cardiorespiratory fitness (CRF), to prescribe exercise intensity and/or to evaluate the effects of training. However, direct measurement of CRF requires a GXT to volitional exhaustion, which may not always be well accepted by athletes or which should be avoided in some clinical populations. Consequently, numerous studies have proposed various sub-maximal exercise tests to predict V˙O2 max or V˙O2 peak . Because of the strong link between ratings of perceived exertion (RPE) and oxygen uptake (V˙O2), it has been proposed that the individual relationship between RPE and V˙O2 (RPE:V˙O2) can be used to predict V˙O2 max (or V˙O2 peak) from data measured during submaximal exercise tests. To predict V˙O2 max or V˙O2 peak from these linear regressions, two procedures may be identified: an estimation procedure or a production procedure. The estimation procedure is a passive process in which the individual is typically asked to rate how hard an exercise bout feels according to the RPE scale during each stage of a submaximal GXT. The production procedure is an active process in which the individual is asked to self-regulate and maintain an exercise intensity corresponding to a prescribed RPE. This procedure is referred to as a perceptually regulated exercise test (PRET). Recently, prediction of V˙O2max or V˙O2 peak from RPE:V˙O2 measured during both GXT and PRET has received growing interest. A number of studies have tested the validity, reliability and sensitivity of predicted V˙O2 max or V˙O2 peak from RPE:V˙O2 extrapolated to the theoretical V˙O2 max at RPE20 (or RPE19). This review summarizes studies that have used this predictive method during submaximal estimation or production procedures in various populations (i.e., sedentary individuals, athletes and pathological populations). The accuracy of the methods is discussed according to the RPE:V˙O2 range used to plot the linear regression (e.g., RPE9–13 versus RPE9–15 versus RPE9–17 during PRET), as well as the perceptual endpoint used for the extrapolation (i.e., RPE19 and RPE20). The V˙O2 max or V˙O2 peak predictions from RPE:V˙O2 are also compared with heart rate-related predictive methods. This review suggests that V˙O2 max (or V˙O2 peak ) may be predicted from RPE:V˙O2 extrapolated to the theoretical V˙O2 max (or V˙O2 peak) at RPE20 (or RPE19). However, it is generally preferable to (1) extrapolate RPE:V ˙ O 2 to RPE19 (rather than RPE20); (2) use wider RPE ranges (e.g. RPE ≤ 17 or RPE9–17) in order to increase the accuracy of the predictions; and (3) use RPE ≤ 15 or RPE9–15 in order to reduce the risk of cardiovascular complications in clinical populations.

Maximal exercise testing: Making it feel better

Introduction: Often regarded as a criterion measure of aerobic fitness, the direct measurement of maximal oxygen uptake (VO2max) requires the individual to exercise to volitional exhaustion. However, the decline in affective state (i.e. how good or bad one feels) throughout a maximal test is rarely considered. The autonomy given to the individual during a perceptually-regulated exercise test (PRET) whereby participants control the exercise intensity would likely induce a more positive affective response compared to a traditional ‘experimenter controlled’ graded exercise test (GXT).

Does a submaximal perceptually-regulated exercise test work with older adults?

Introduction: An accurate measure of peak oxygen uptake (VO2peak) is an important indicator of cardiorespiratory fitness. In older adults significant concerns for safety are associated with using tests which push participants to volitional exhaustion to measure actual VO2peak. There are a number of indirect methods to predict VO2max, although the validity and reliability of these methods are questionable. Recently, VO2peak was reliably predicted in young adults using a submaximal perceptually-regulated exercise test (PRET).

Use of a perceptually-regulated test to measure maximal oxygen uptake is valid and feels better

A maximal, perceptually-regulated exercise test (PRETmax) whereby participants control the intensity according to preset ratings of perceived exertion (RPE) may induce more positive affective responses than a conventional ‘experimenter controlled’ incremental ramp test (Iramp). The authors aimed to assess (1) if a PRETmax could be used to measure O2max and (2) if affective responses differed between the PRETmax and Iramp. Sixteen participants (age 20.5, s=1.2 y) completed a PRETmax which required them to adjust the resistance on a recumbent cycle ergometer to correspond to prescribed RPEs of 9, 11, 13, 15, 17 and 20 and an Iramp. Both tests ended with volitional exhaustion. Affect was recorded every minute throughout exercise using the Feeling Scale (FS). There was no difference (P>0.05) between O2max measured by PRETmax (43.5, s=4.1 ml kg−1 min−1) and Iramp (44.3, s=4.9 ml kg−1 min−1). Participants reported feeling significantly less negative (P<0.001) throughout the PRETmax compared to Iramp (average mean difference FS = 1.4, s=0.1). The PRETmax has application in situations where the direct measurement of O2max is required and the affective responses of the individual are considered to be important.

The perceptually regulated exercise test is sensitive to increases in maximal oxygen uptake

The aim of this study was to assess the sensitivity of a perceptually regulated exercise test (PRET) to predict maximal oxygen uptake (VO₂max) following an aerobic exercise-training programme. Sedentary volunteers were assigned to either a training (TG n = 16) or control (CG n = 10) group. The TG performed 30 min of treadmill exercise, regulated at 13 on the Borg Rating of Perceived Exertion (RPE) Scale, 3× per week for 8 weeks. All participants completed a 12-min PRET to predict VO₂max followed by a graded exercise test (GXT) to measure VO₂max before and after training. The PRET required participants to control the speed and incline on the treadmill to correspond to RPE intensities of 9, 11, 13 and 15. Predictive accuracy of extrapolation end-points RPE19 and RPE20 from a submaximal RPE range of 9-15 was compared. Measured VO₂max increased by 17 % (p < 0.05) from baseline to post-intervention in TG. This was reflected by a similar change in [VO₂max predicted from PRET when extrapolated to RPE 19 (baseline VO₂max: 31.3 ± 5.5, 30.3 ± 9.5 mL kg(-1) min(-1); post-intervention VO₂max: 36.7 ± 6.4, 37.4 ± 7.9 mL kg(-1) min(-1), for measured and predicted values, respectively). There was no change in CG (measured vs. predicted VO₂max: 39.3 ± 6.5; 40.3 ± 8.2 and 39.2 ± 7.0; 37.7 ± 6.0 mL kg(-1) min(-1)) at baseline and post-intervention, respectively. The results confirm that PRET is sensitive to increases in VO₂max following aerobic training.

A perceptually regulated, graded exercise test predicts peak oxygen uptake during treadmill exercise in active and sedentary participants

The validity of predicting peak oxygen uptake ([Formula: see text]) in sedentary participants from a perceptually regulated exercise test (PRET) is limited to two cycle ergometry studies. We assessed the validity of a treadmill-based PRET. Active (n = 49; 40.7 ± 13.8 years) and sedentary (n = 26; 33.4 ± 13.2 y) participants completed two PRETS (PRET 1 and PRET2), requiring a change in speed or incline corresponding to ratings of perceived exertion (RPE) 9, 11, 13 and 15. Extrapolation of RPE: [Formula: see text] data to RPE 19 and 20 from the RPE 9-13 and 9-15 ranges were used to estimate [Formula: see text], and compared to [Formula: see text] from a graded exercise test (GXT). The [Formula: see text] :heart rate (HR) data (≥RPE 15) from the GXT were also extrapolated to age-predicted maximal HR (HRmax(pred)) to provide further estimation of [Formula: see text]. ANOVA revealed no significant differences between [Formula: see text] predictions from the RPE 9-15 range for PRET 1 and PRET 2 when extrapolated to RPE 19 in both active (54.3 ± 7.4; 52.9 ± 8.1 ml kg(-1) min(-1)) and sedentary participants (34.1 ± 10.2; 34.2 ± 9.6 ml kg(-1) min(-1)) and no difference between the HRmax(pred) method and measured [Formula: see text] from the GXT for active (53.3 ± 10.0; 53.9 ± 7.5 ml kg(-1) min(-1), respectively) and sedentary participants (33.6 ± 8.4, 34.4 ± 7.0 ml kg(-1) min(-1), respectively). A single treadmill-based PRET using RPE 9-15 range extrapolated to RPE 19 is a valid means of predicting [Formula: see text] in young and middle to older-aged individuals of varying activity and fitness levels.

The validity and reliability of predicting maximal oxygen uptake from a treadmill-based sub-maximal perceptually regulated exercise test

The purpose of this study was to determine for the first time whether VO2max could be predicted accurately and reliably from a treadmill-based perceptually regulated exercise test (PRET) incorporating a safer and more practical upper limit of RPE 15 ("Hard") than used in previous investigations. Eighteen volunteers (21.7 +/- 2.8 years) completed three treadmill PRETs (each separated by 48 h) and one maximal graded exercise test. Participants self-regulated their exercise at RPE levels 9, 11, 13 and 15 in a continuous and incremental fashion. Oxygen uptake VO2 was recorded continuously during each 3 min bout. VO2 values for the RPE range 9-15 were extrapolated to RPE(19) and RPE(20) using regression analysis to predict individual VO2max scores. The optimal limits of agreement (LoA) between actual (48.0 +/- 6.2 ml kg(-1) min(-1)) and predicted scores were -0.6 +/- 7.1 and -2.5 +/- 9.4 ml kg(-1) min(-1) for the RPE(20) and RPE(19) models, respectively. Reliability analysis for the VO2max predictions yielded LoAs of 1.6 +/- 8.5 (RPE(20)) and 2.7 +/- 9.4 (RPE(19)) ml kg(-1) min(-1) between trials 2 and 3. These findings demonstrate that (with practice) a novel treadmill-based PRET can yield predictions of VO2max that are acceptably reliable and valid amongst young, healthy, and active adults.

Predicting Maximal Oxygen Uptake Via a Perceptually Regulated Exercise Test (PRET)

Recent research has yielded encouraging, yet inconsistent findings concerning the validity and reliability of predicting maximal oxygen uptake ( O 2max ) from a graded perceptually regulated exercise test (PRET). Accordingly, the purpose of the present study was to revisit the validity and reliability of this application of ratings of perceived exertion (RPE) using a modified PRET protocol. Twenty-three volunteers (mean age, 31 ± 9.9 years) completed four counter-balanced PRETs (involving two 2-minute and two 3-minute bouts administered over 9 days, each separated by 48 hours) on an electromagnetically braked cycle ergometer and one maximal graded exercise test. Participants self-regulated their exercise at RPE levels 9, 11, 13, 15 and 17 in a randomized order. Oxygen uptake ( O 2 ) was recorded continuously during each bout. The O 2 values for the RPE ranges 9–17, 9–15 and 9–13 were extrapolated to RPE 20 using regression analysis to predict individual O 2max scores. The concordance of the predicted and actual O 2max scores and the trial-to-trial reliability of the predicted scores were analyzed using the limits of agreement (LoA) technique. The LoA between actual (41.5 ± 8.0 mL·kg −1 ·min −1 ) and predicted O 2max scores for the RPE range 9–17 were −2.6 ± 10.1 and −1.3 ± 7.4 mL·kg −1 ·min −1 (2-minute bout) and −1.0 ± 9.2 and 0.2 ± 7.2 mL·kg −1 ·min −1 (3-minute bout) for trials 1 and 2, respectively. Reliability analysis yielded LoA of −1.3 ± 9.2 mL·kg −1 ·min −1 (2-minute bout) and −0.8 ± 5.7 mL·kg −1 ·min −1 (3-minute bout). The modified PRET provided acceptable and repeatable estimates of O 2max , suggesting its application in environments where maximal tests are inappropriate, and is worthy of further investigation.

The validity of predicting maximal oxygen uptake from a perceptually-regulated graded exercise test

The purpose of this study was to assess the validity of predicting maximal oxygen uptake(VO(2max)) from sub-maximal VO(2) values elicited during a perceptually-regulated exercise test. We hypothesised that the strong relationship between the ratings of perceived exertion (RPE) and VO(2) would enable VO(2max) to be predicted and that this would improve with practice. Ten male volunteers performed a graded exercise test (GXT) to establish VO(2max) followed by three sub-maximal RPE production protocols on a cycle ergometer, each separated by a period of 48 h. The perceptually-regulated trials were conducted at intensities of 9, 11, 13, 15 and 17 on the RPE scale, in that order. VO(2) and HR were measured continuously and recorded at the end of each 4 min stage. Individual's RPE values yielded correlations in the range 0.92-0.99 across the three production trials. There were no significant differences between measured VO(2max) (48.8 ml.kg(-1).min(-1)) and predicted VO(2) max values (47.3, 48.6 and 49.9 ml.kg(-1).min(-1), for trials 1, 2 and 3, respectively) when VO(2) max was predicted from RPE values of 9-17. The same was observed when VO(2max) was predicted using RPE 9-15. Limits of agreement (LoA) analysis on actual and predicted VO(2max) values (from RPE 9-17) were (bias+/-1.96xSDdiff) 1.5+/-7.3, 0.2+/-4.9 and -1.2+/-5.8 ml.kg(-1).min(-1), for trials 1, 2 and 3, respectively. Corresponding LoA values for actual and predicted VO(2max) (from RPE 9-15) were 5.4+/-11.3, 4.4+/-8.7 and 2.3+/-8.4 ml.kg(-1).min(-1), respectively. The data suggest that a sub-maximal, perceptually-guided, graded exercise protocol can provide acceptable estimates of maximal aerobic power, which are further improved with practice in fit young males.