Rating Of Perceived Exertion Scale Research Articles

#596 The Borg Scale—efficient and safe for exercise prescription in self-administered balance and strength exercise in patients with CKD

Abstract Background and Aims With the continued rise in chronic kidney disease (CKD), there is a critical need for sustainable, home-based exercise interventions. While supervised, centre-based exercise improves physical performance in CKD patients, unsupervised, self-administered exercise poses challenges in ensuring adherence, safety, and efficacy. This study investigates the Borg Rating of Perceived Exertion (RPE) scale, a subjective measure of exertion, as a method for prescribing and monitoring the intensity of balance and strength exercise in non-dialysis dependent CKD patients. The aims of this study were: Method This sub study of the RENEXC-trial included 148 patients with CKD stages 3-5, with a mean age of 66 ± 14 years and mean measured GFR of 22 ± 8 ml/min/1.73 m2. Patients were prescribed 90 minutes/week of balance or strength exercise at a Borg RPE of 13-17 (corresponding to an exercise intensity of somewhat hard to very hard), along with 60 minutes/week of endurance exercise. Exercise programs were individually prescribed by a physiotherapist according to randomization and each patient's baseline performance and were performed at home or in a gym according to the patient's preference. Duration and RPE of the performed exercise were reported in an exercise diary. Progress was monitored by the physiotherapist through phone contact, every week for the first three months of the study and every other week for the rest of the study year. The continuous follow up provided motivation and enabled adjustments of the exercise program to maintain the goal RPE, adapt intensity and the weekly duration of exercise. Outcome measures included the Berg Balance Scale (BBS) and Functional Reach Test (FRT), the 30-second sit-to-stand test (30STS) and isometric quadriceps strength (IQS). Balance and strength measures were evaluated at baseline and after 12 months of exercise. Previous publications of the RENEXC-trial showed no difference between patients who performed balance exercise and patients who performed strength exercise; therefore, this sub-study analysed all included patients as one group. Results Of 148 participants, 112 completed the study. At 12 months, 79% reported performed exercise, with 86% of these patients adhering to the prescribed intensity. The median (25th-75th percentile) exercise intensity was a RPE of 14 (13-15) on the Borg scale, and the median (min-max) exercise duration was 48 (0-241) minutes/week. Only 18% of the patients reached the 90-minute/week target. No exercise-related incidents were reported. Significant improvements were noted in BBS (p = 0.0464), FRT (p = 0.009), 30STS (p = 0.047), and IQS (right/left p = 0.022 / p = 0.049). Conclusion The Borg RPE scale is an effective and safe method for prescribing and monitoring self-administered balance and strength exercise in patients with CKD. Using the Borg scale for prescribing and monitoring exercise intensity during balance and strength exercise resulted in a good level of adherence to the 12-months exercise program and the prescribed exercise intensity. As no exercise related incidents were reported, we conclude that the self-administered exercise was safe to perform. Significant improvements in balance and strength were observed with a moderate to high exercise intensity prescription within a wide range of performed weekly duration of exercise, suggesting the Borg scale's value in exercise prescription in both well- and deconditioned patients with CKD. These findings show that the integration of the Borg scale into routine exercise prescription in people with CKD can promote patient autonomy and efficient resource utilization in healthcare.

The relationship between prescribed ratings of perceived exertion and force production in repeated isometric contractions

Ratings of perceived exertion (RPE) are frequently used to monitor and prescribe exercise intensity. However, studies examining the shape and robustness of how feelings of effort map onto objective outputs are limited and report inconsistent results. To address this, we investigated whether (1) producing isometric forces according to RPE levels reliably leads to differences in force output, (2) if feelings of effort map linearly or non-linearly onto force output, and (3) if this mapping is robust when visual feedback and social facilitation are present. In a counterbalanced repeated measures design, N = 26 participants performed isometric handgrip contractions prescribed by ten levels of the Borg CR-10 scale. They did so either with or without the availability of concurrent visual feedback regarding their force production, and in the presence or absence of another person performing the same task simultaneously. We found that subjects reliably produced different force outputs that corresponded to each RPE level. Furthermore, concurrent visual feedback led to a linearization of force output, while in the absence of feedback, the produced forces could also be described by quadratic and cubic functions. Exploratory post-hoc analyses revealed that participants perceived moderate RPE levels to be more challenging to produce. By shedding light on the dynamic nature of the mapping between RPE and objective performance, our findings provide helpful insights regarding the utility of RPE scales.

ASSESSMENT OF A SELF-PACED PROTOCOL FOR TESTING AEROBIC CAPACITY IN SCI INDIVIDUALS

BACKGROUND Underwater treadmill (UT) exercise is a recent and sparsely tested modality that may be beneficial for those with incomplete spinal cord injury (iSCI). Currently, VO2max and HRmax have not been assessed during UT exercise among those with iSCI. This study's purpose was to determine if a rating of perceived exertion (RPE) based max exertion protocol used with a motorized UT can elicit criterion-based max physiological responses among those with and without iSCI. METHODS Healthy adult males with iSCI (n=4; Age=49.8 +/- 3.9 yrs) and without iSCI (n=4; Age=50.0 +/- 7.2 yrs) participated. Borg OMNI RPE scale was used by participants to estimate intensity of exercise. Each participant reported to the lab on two occasions. On visit one, they completed informed consent papers and familiarization with the RPE scale and UT exercise. On visit two, they completed a speed-based, self-regulated incremental exercise test on the UT. Prior to all testing, the UT was filled and set to 92°F. Upon arrival, HR monitor and mask for gas collection were donned. Water height was modified to the xiphoid process. The test consisted of rest, warm-up, incremental exercise, and active recovery phases. For warm-up, treadmill speed was adjusted to 0.5 mph for 3 minutes. After walking 3 minutes, speed was increased to 0.75 mph for another 3 minutes. The incremental exercise phase consisted of four stages, 3 minutes in duration, totaling 12 minutes. For each stage, participants self-selected a speed perceived to correspond to RPE levels: 3, 5, 7, and 10. Treadmill speed was hidden from participants. At each stage's start, speed was only adjusted during the first minute until reaching the proper RPE. During the final stage, treadmill speed could be changed freely until volitional exhaustion. The test ended when volitional exhaustion was reached, at which point the speed was lowered for an active recovery. An independent samples t-test was used to compare time (minutes) until volitional exhaustion. Separate independent samples t-tests were used to compare the highest achieved HR and VO2 values. RESULTS All iSCI participants achieved a VO2peak. Only 1 participant without iSCI achieved a VO2max. Mean VO2 was significantly lower, t(6)=3.81, p=.027, for those with iSCI (13.88 +/- 10.57 mL/kg/min) than those without iSCI (34.50 +/- 2.38 mL/kg/min). CONCLUSION This study shows that the UT is a safe modality for graded exercise testing for those with and without iSCI. An RPE-regulated protocol may not be effective for eliciting criterion-based maximal aerobic results with the UT, but was well tolerated by those with iSCI. Those with iSCI may have lacked lower limb strength to achieve max workloads. Being able to use the UT to test peak aerobic fitness allows clinicians to track improvements in economy following UT training. More research of this modality is encouraged with larger samples to further evaluate potential testing protocols among this population.

Differential ratings of perceived exertion to quantify weekly and sessional internal load in basketball: an exploratory team-based case series

Although differential rating of perceived exertion (RPE) scales have been supported in quantifying internal load across various sports, their application in basketball remains to be comprehensively investigated. Consequently, we aimed to: (1) quantify and compare session- and weekly-RPE loads using global and differential RPE scales; and (2) compare session-RPE load between individual sessions across the week using each scale in basketball players. Ten semiprofessional, male players reported RPE using global and differential (respiratory and muscular) scales following each training session and game during the in-season. RPE was multiplied by session duration to derive session-RPE load, which were summed to determine weekly-RPE load. Weekly-RPE load was higher using global (P = 0.003, η2 = 0.343, large) and muscular (P = 0.004, η2 = 0.209, large) scales than the respiratory scale. Likewise, session-RPE load was higher using global (P = 0.049, η2 = 0.314, large) and muscular (P = 0.054, η2 = 0.298, large) scales than the respiratory scale only in games, with differences between scales during other sessions being trivial-to-medium (P >0.05). Across all scales, higher session-RPE loads were apparent in the second training session than all other sessions in the week (P <0.05, η2 = 0.105– 0.561, medium-to-large), and during games than the first training session (P <0.001, η2 = 0.202–0.223, large). While session-to-session load changes were similarly detected across scales, the greater weekly and game muscular loads than respiratory loads support the potential for differential RPE scales to provide more detailed internal load data in basketball settings.

Enhancing physiological recovery and subsequent exercise performance in the heat using a phase-change material cooling blanket

This study aimed to assess the effect of a phase-change material (PCM) cooling blanket for cooling between exercise bouts on recovery of physiological parameters and subsequent exercise performance in the heat. Eighteen male volunteers were recruited to participate in human trials involving two exhaustive treadmill running bouts (Bout1 for 3 km and Bout2 for 1.5 km) in a climate chamber (temperature = 33 °C; relative humidity = 40%). Participants were randomly subjected to one of two cooling conditions for a 10-min period between exercise bouts: CON: natural cooling; 10-min PCM: with a PCM cooling blanket for 10 min. Several physiological parameters including mean skin temperature (Tskin), oral temperature (Toral), core temperature (Tcore), heart rate (HR), mean arterial pressure (MAP), respiratory rate (RR), peripheral capillary oxygen saturation (SpO2), average running speed and rating of perceived exertion (RPE) scale score were analyzed. The results showed that compared to the CON group, participants in the 10-min PCM group had a significant lower Tskin, Tcore, HR and RR at post-cooling, as well as greater reductions in mean skin temperature (ΔTskin) and core temperature (ΔTcore) from post-Bout1 to post-cooling. Additionally, the 10-min PCM group exhibited significantly lower peak Tcore, peak HR and RPE scale score during Bout2, while the average running speed during Bout2 was significantly higher. The present study suggests that cooling with a PCM cooling blanket can enhance physiological recovery and subsequent exercise performance in the heat.

Is rating of perceived exertion a valid method for monitoring exergaming intensity in type-1 diabetics? A cross-sectional randomized trial

AimsThe rating of perceived exertion (RPE) provides correlations with physiological measurements of exercise intensity, including metabolic equivalent (MET), oxygen consumption (V˙O2), and heart rate (HR), in real (RS) and virtual (VS) sessions. To use RPE in patients with pathology, we aimed to examine the concurrent validity of RPE in type-1 diabetes mellitus (T1DM) patients while exergaming. MethodsTen T1DM patients performed two 30-min crossover sessions of moderate-intensity exercise (washout 72-196 h). The RS group performed running, and the VS group played the Kinect Adventures! video game. METs were measured by a direct gas analyzer during the sessions, and RPE was measured on the 6 - 20 point Borg scale after the sessions. ResultsRS and VS showed similar RPE (13.2 ± 2.7 vs. 14.2 ± 2.4) and MET (4.6 ± 1.1 vs. 4.0 ± 0.8) values (p > 0.05). RPE vs. MET correlation-coefficients were large in RS (r = 0.64; R2 = 41; p = 0.04) and were moderate in VS (r = 0.42; R2 = 18; p = 0.22). Additionally, RS secondary values (V˙O2 and HR vs. RPE) showed high coefficients (V˙O2-r = 0.62; average HRr = 0.62; maximal HRr = 0.50, p < 0.05). VS secondary values, on the other hand, showed low-moderate coefficients (V˙O2-r = 0.42; average HRr = 0.23; maximal HRr = 0.21, p > 0.05). ConclusionThe current validation showed that RPE may not be a valid and strong method for T1DM patients while exergaming. Healthcare professionals should cautiously use the 6 – 20 point RPE scale in pathological patients, specifically in T1DM while exergaming.

Moderate-to-vigorous intensity cycling exercise immediately after visual learning enhances delayed recognition memory performance

A single bout of acute aerobic exercise has been shown to improve long-term memory, though it is unclear if exercise before learning or after learning is optimal for memory enhancement. Although some research has demonstrated that exercise before learning is ideal, investigations have consistently shown that acute arousal post-learning is a powerful memory enhancer. Therefore, the purpose of this investigation was to compare the effects of self-perceived hard cycling before or after learning on recognition memory for emotional and neutral images, and examine the relationship between central noradrenergic activity and memory performance. Seventy-two males and females (18–35 years of age) participated in this between-subjects study. Participants were randomly assigned to one of the following groups: exercise before learning, exercise after learning, and control. Participants in the exercise groups engaged in 20 min of cycling at a rating of perceived exertion (RPE) of 15 (“hard”) on the Borg RPE scale before or after viewing a series of 90 pleasant, unpleasant, and neutral images (30 each). Participants in the control group engaged in no exercise before or after image viewing. At several time points throughout the experiment, saliva was collected to measure salivary alpha amylase (sAA), a marker of central noradrenergic activity. One-week later, recognition memory was assessed where participants viewed 180 images (90 new) and had to identify which images were previously viewed. Participants in the exercise after learning group had significantly higher recognition memory compared to the control group, but this was not seen with exercise before learning. sAA was not correlated with memory in any group, though it did increase during exercise. These results demonstrate that acute self-perceived hard cycling post-learning, but not pre-learning, improves recognition memory, though this was unrelated to the exercise-induced increase in central noradrenergic activity as measured in saliva.

Validity of Weekly and Monthly Perceived Exertion in Runners.

The development of the rating of perceived exertion (RPE) enables the easy assessment of runners' training strain as well as training load (TL). However, the long-term and retrospective validity of TL assessment using RPE scales still needs further investigation. Therefore, this study examined the validity of weekly and monthly ratings of perceived exertion (W-RPE, M-RPE) in assessing TL in runners. Healthy adult runners (n=53) rated perceived exertion using the modified category-ratio 10 (CR-10) scale for each week of a four-week period, as well as for the month, considering the four-week period. CR-10 for the week and the month were multiplied by the total training time of the week and month, respectively, to assess the W-RPE and M-RPE. Training impulse (TRIMP) was used as the criterion measure. The results indicated that the W-RPE and M-RPE may be used for monitoring TL during prolonged periods, presenting a very large correlations with the criterion measure.

Clinical studies on the electric automatic massage therapy for recovery of acute sports fatigue.

Acute sports fatigue impairs athletes' performance and causes other health issues; therefore, an effective method of relieving acute sports fatigue is being researched. The present study was envisaged to evaluate the effect of electric auto-massage therapy and proprioceptive neuromuscular facilitated (PNF) stretching method on the recovery of acute exercise fatigue using the heart rate variability-based multi-physiological index and RPE scale, and to explore the underlying principle and mechanism. Sixty volunteers were divided into the stretching group, massage group and control group (20 subjects each) using the complete randomization method. The massage group chose the kneading, pressing, tapping and patting techniques using the intelligent massage chair to intervene on the volunteers, the stretching group chose the PNF stretching method to intervene on the volunteers, while the control group did not adopt any of these techniques. The Rating Of Perceived Exertion (RPE) score, heart rate (HR), grip strength, skin electrical activity, heart rate variability (HRV) and blood oxygen saturation (SpO2) of the three groups were recorded before and after the intervention. Before the intervention, there was no statistically significant difference between the values of heart rate variability (HRV) in the three groups (P> 0.05), while after the intervention, there was a statistically significant difference between the values of heart rate variability - low frequency/high frequency (HRV (LF/HF)) and HRV (HF) in the three groups as: HRV (HF): ηH2= 0.10; P= 0.022; HRV (LF/HF): ηH2= 0.44; P= 0.001. The results indicated that the different intervention methods presented substantial effects on the values of HRV (HF) and HRV (LF/HF) in the volunteers. The HRV (HF) values of massage group, stretching group and control group were compared, and the difference between the massage group and control group was statistically significant (P= 0.019). Further, the HRV (HF) values of massage group rose more significantly than control group after the intervention, and the difference between HRV (HF) values of massage group and stretching group was not statistically significant. When comparing the HRV (LF/HF) values of massage group, stretching group and control group, the differences between the massage group and stretching group and control group were statistically significant (P= 0.001, P< 0.05), and it was observed that the HRV (LF/HF) values of massage group decreased more significantly than those of stretching group and control group after the intervention. The difference in HRV (LF) values between the three groups after the intervention was not statistically significant (P> 0.05). 1. It was observed that the electric automatic massage therapy played a vital role in the rapid relief of exercise fatigue by soothing and regulating the human phototropic system, reducing vagal tone, and accelerating the excretion of metabolites; while PNF stretching relieved the exercise fatigue by providing physical and verbal communication to transfer the perception of fatigue, and by promoting the excretion of metabolites through muscle isometric contraction. 2. The effect of electric auto-massage therapy was marginally stronger than the commonly used PNF stretching exercise method.

Association between internal load responses and recovery ability in U19 professional soccer players: A machine learning approach

BackgroundThe objective of soccer training load (TL) is enhancing players’ performance while minimizing the possible negative effects induced by fatigue. In this regard, monitoring workloads and recovery is necessary to avoid overload and injuries. Given the controversial results found in literature, this study aims to better understand the complex relationship between internal training load (IL) by using rating of perceived exertion (RPE), recovery, and availability (i.e., subjective players’ readiness status). MethodsIn this cross-sectional study, twenty-two-professional soccer players (age: 18.5 ± 0.4 years, height: 177 ± 6 cm, weight: 67 ± 6.7 kg) competing in the U19 Italian Championship were monitored using RPE scale to assess IL, and TreS scale to detect information about recovery and training/match availability during an entire season (2021–2022). ResultsAutocorrelation analysis showed a repeated pattern with 7 days lag (weekly microcycle pattern) for all the variables considered (i.e., TL, recovery, and availability). For recovery (r = 0.64, p < 0.001) and availability (r = 0.63, p < 0.001) the best lag for both of them is 1 day. It indicates that recovery and availability are related to the past day value. Moreover, TL was found to be negatively affected by recovery and availability of the current day (lag = 0 day). Cross-correlation analysis indicates that TL is negatively affected by recovery (r = 0.46, p < 0.001) and availability (r = 0.42, p < 0.001) of the current day (lag = 0 day). In particular, lower recovery and availability will result in following lower TL. Furthermore, we found that TL negatively affects recovery (r = 0.52, p < 0.001) and availability (r = 0.39, p < 0.01) of the next day (lag = 1 day). In fact, the higher the TL in a current day is, the lower the recovery and availability in the next day will be. ConclusionIn conclusion, this study highlights that there is a relationship between TL and recovery and that these components influence each other both on the same day and on the next one. The use of RPE and TreS scale to evaluate TL and recovery/availability of players allows practitioners to better adjust and schedule training within the microcycle to enhance performance while reducing injury risk.

Sex- and age-related differences in the rating of perceived exertion after high-intensity rowing exercise during childhood and adolescence.

The present study aimed to evaluate the effects of age and sex on the rating of perceived exertion (RPE) during high-intensity exercise and determine whether mechanical and physiological parameters could be predictors of RPE during childhood and adolescence. Forty-three boys and 36 girls performed a 60-s all-out test on a rowing ergometer and were categorized by age group (10.0-11.9; 12.0-13.9; 14.0-15.9; 16.0-17.9 years) and sex. Ratings of perceived exertion were assessed using the 6-20 RPE and CR-10 scales and analyzed with respect to mechanical work rate (Wtot ), post-exercise peak blood lactate concentration ([La]peak ), and peak minute ventilation (V̇Epeak ). Multilevel regression modeling revealed a significant influence of Wtot , [La]peak and V̇Epeak on 6-20 RPE and CR-10 scores (r2 =.34 and .36, p < .001, respectively). However, while boys perceived high-intensity exercise as being subjectively more difficult than girls at all ages (p < .05) except 12.0-13.9 years, significant higher mechanical work rate and greater associated metabolic responses in boys than girls were only found from the age of 14 years (Wtot and V̇Epeak ) or 16 years ([La]peak ), suggesting that the association between RPE and mechanical/physiological parameters could not be held before the age of 12 years. To conclude, RPE increased with increasing age, with boys exhibiting higher scores than girls at all ages except 12.0-13.9 years. This finding is probably explained by the higher Wtot and greater concomitant metabolic responses in boys at the time of puberty. However, other factors should be considered at least in children before the age of 12 years.

Different physiological, but similar affective responses, facing different workload quantification methods

Backgroung: The literature provides support for several different method by which it is possible to quantify, prescribe and control the aerobic workload. Objective: To compare physiological and the affective response among training methods prescribed by VO2 reserve, HR reserve, and rating of perceived exertion (RPE) self-adjusted. Methods: 27 participants were submitted to two trail sessions. In the 1st, a maximum treadmill effort test was performed to determine the VO2max. In the 2nd, the participants were randomly divided into 3 situations of 5 min, with 5 min interval among the situations. In situation 1 (C1), the participants ran at the velocity correspondent to 65% of the VO2 reserve; in situation 2 (C2), participants ran at 60% to 65% of HR reserve and in situation 3 (C3), the participants self-adjustment the velocity by a RPE scale, in a moderate effort (RPE 3-4). The level of body activation and the affective response were obtained pre and post-stimulus administered. An ANOVA was performed and the magnitude of the differences established, with a significance level of p ≤ 0.05. Results: There were no significant differences for velocity in the three situations (p = 0.458). The responses of HR induced by C1 and C3 were significantly higher vs. C2 (p = 0.027 and p = 0.043). The RPE did not show significant differences among the situations (p = 0.118). Finally, the level of activation and sensation perceived activity did not differ significantly (p = 0.168). Conclusion: It was concluded that the exercise responses from the HR reserve were significantly lower when compared to the VO2reserve and RPE. All prescription models provided similar affective responses.

Measuring the Effect of Off-Balancing Vectors on the Delivery of High-Quality CPR during Ambulance Transport: A Proof of Concept Study

Aim This study aims to demonstrate the feasibility of quantifying the off-balancing vectors experienced during ambulance transport and comparing them to high-quality cardiopulmonary resuscitation (HQ-CPR) metrics. Methods Ten participants completed a total of 20 evolutions of compression-only HQ-CPR in an ambulance driven in a manner that minimized or increased linear and angular off-balancing vectors. Linear and angular velocity, linear and angular acceleration, and linear jerk were recorded. HQ-CPR variables measured were compression fraction and proportion of compressions with depth >5 cm (depth%), rate 100–120 (rate%), full chest recoil (recoil%), and hand position (hand%). A composite score was calculated: [(depth% + rate% + recoil% + hand%)/4) * compression fraction]. Difficulty of HQ-CPR performance was measured with the Borg rating of perceived exertion (RPE) Scale. A series of mixed effects models were fitted regressing each HQ-CPR metric on each off-balancing vector. Results HQ-CPR data and vector quantity data were successfully recorded in all evolutions. Rate% was negatively associated with increasing linear velocity (slope = −3.82, standard error [SE] 1.12, p = 0.005), linear acceleration (slope = −5.52, SE 1.93, p = 0.013), linear jerk (slope = −17.60, SE 5.78, p = 0.007), angular velocity (slope = −75.74, SE 22.72, p = 0.004), and angular acceleration (slope = −152.53, SE 59.60, p = 0.022). Compression fraction was negatively associated with increasing linear velocity (slope = −1.35, SE 0.37, p = 0.004), linear acceleration (slope = −1.67, SE 0.48, p = 0.003), linear jerk (slope = −4.90, SE 1.86, p = 0.018), angular velocity (slope = −25.66, SE 6.49, p = 0.001), and angular acceleration (slope = −45.35, SE 18.91, p = 0.031). Recoil% was negatively associated with increasing linear velocity (slope = −5.80, SE 2.21, p = 0.023) and angular velocity (slope = −116.96, SE 44.24, p = 0.019)). Composite score was negatively associated with increasing linear velocity (slope = −4.49, SE 1.45, p = 0.009) and angular velocity (slope = −86.13, SE 31.24, p = 0.014) and approached a negative association with increasing magnitudes of linear acceleration (slope −5.54, SE 2.93, p = 0.075), linear jerk (slope = −17.43, SE 8.80, p = 0.064), and angular acceleration (slope = −170.43, SE 80.73, p = 0.051). Borg RPE scale was positively associated with all off-balancing vectors. Depth%, hand%, mean compression depth, and mean compression rate were not correlated with any off-balancing vector. Conclusion Off-balancing vector data can be successfully quantified during ambulance transport and compared with HQ-CPR performance parameters. Increasing off-balancing vectors experienced during ambulance transport are associated with worse HQ-CPR metrics and increased perceived physical exertion. These data may help guide future drive styles, ambulance design, or use of mechanical CPR devices to improve HQ-CPR delivery during selected patient transport scenarios.

Perceptions of fatigue and neuromuscular measures of performance fatigability during prolonged low-intensity elbow flexions.

What is the central question of this study? What is the predictive relationship between self-reported scales to quantify perceptions of fatigue during exercise and gold standard measures used to quantify the development of neuromuscular fatigue? What is the main finding and its importance? No scale was determined to be substantively more effective than another. However, the number of ongoing contractions performed was shown to be a better predictor of fatigue in the motor system than any of the subjective scales. The purpose of this study was to determine the relationship between transcranial magnetic stimulation (TMS) measures of performance fatigability and commonly used scales that quantify perceptions of fatigue during exercise. Twenty healthy participants (age 23±3years, 10 female) performed 10 submaximal isometric elbow flexions at 20% maximal voluntary contraction (MVC) for 2min, separated by 45s of rest. Biceps brachii muscle electromyography and elbow flexion torque responses to single-pulse TMS were obtained at the end of each contraction to assess central factors of performance fatigability. A rating of perceived exertion (RPE) scale, Omnibus Resistance scale, Likert scale, Rating of Fatigue scale and a visual analogue scale (VAS) were used to assess perceptions of fatigue at the end of each contraction. The RPE (root mean square error (RMSE)=0.144) and Rating of Fatigue (RMSE=0.145) scales were the best predictors of decline in MVC torque, whereas the Likert (RMSE=0.266) and RPE (RMSE=0.268) scales were the best predictors of electromyographic amplitude. Although the Likert (RMSE=7.6) and Rating of Fatigue (RMSE=7.6) scales were the best predictors of voluntary muscle activation of any scale, the number of contractions performed during the protocol was a better predictor (RMSE=7.3). The ability of the scales to predict TMS measures of performance fatigability were in general similar. Interestingly, the number of contractions performed was a better predictor of TMS measures than the scales themselves.

Efficacy of Buteyko Breathing Technique on Anxiety, Depression and Self Efficacy in Coronary Artery Bypass Graft Patients: A Randomised Clinical Trial

Introduction: Psychiatric issues, particularly depression and anxiety, have been observed in the proportions of patients undergoing cardiovascular surgery.Such findings provide a window of opportunity for integrating intervention, targeting psychological components into post-Coronary Artery Bypass Graft (CABG) patient management to provide effective care. The Buteyko Breathing Technique (BBT), which is named after its inventor Konstantin Pavlovich Buteyko, is one of the numerous breathing techniques that aims to regulate breathing. By alternating between periods of controlled breathing reduction and breath holding. Aim: To explore the effect of BBT as a psychological rehabilitation technique on anxiety, depression, and self-efficacy in postCABG subjects having anxiety and depression. Materials and Methods: This randomised clinical trial was performed at Cardiovascular and Thoracic Surgery Unit, Acharya Vinobha Bhave Rural Hospital, Sawangi, Wardha, Maharashtra, India, from June 2021 to May 2022. Total 44 post CABG patients who all screened positive for anxiety and depression by General Anxiety Disorder-7 (GAD-7) questionnaire and Patient Health Questionnaire-9 (PHQ-9) were enrolled. They were randomly assigned using computed generated block randomisation. They were allocated using the Sequentially Numbered Opaque Sealed Envelope (SNOSE) method to group A Conventional group (n=22) and group B Experimental group (n=22). Both groups competed the in-hospital phase 1 cardiac rehabilitation as per American Association of Cardiovascular and Pulmonary Rehab (AACVPR) guidelines, whereas group B received additional BBT for psychosocial rehabilitation for 2 weeks post surgery. The evaluations were performed using the GAD-7 questionnaire, PHQ-9, General Self-Efficiency Scale (GSS), Breath Holding Test (BHT), and Borg Rate of Perceived Exertion Scale (RPE), at baseline on Post Operative Day (POD)1 and at their last rehabilitation session. Patients in both groups were given self management and education hand-outs at the time of discharge. Statistical Package for Social Sciences (SPSS) version 27.0 was used for statistical analysis. Results: The mean age of patients in A-group was 59.72±7.84 years and in B-group 60.81±7.42 years, respectively. The age, gender, height, weight, and BMI of the patients were similar between the groups. On intra group comparison ,there was statistically significant difference observed for GAD-7, PHQ-9, GSS, BHT, and RPE in group A and group B following the intervention, but the change was more pronounced in group B. The results for the inter group comparison showed a significant difference in group B on Anxiety, Depression, self-efficacy, BHT, and RPE as compared to the group A, i.e. group B showed a larger improvement in outcome measure scores than group A. Conclusion: The present study demonstrated that On intra group weeks of BBT along with phase 1 cardiac rehabilitation in post CABG patients brings favourable changes in levels of anxiety, depression and self-efficacy.

Chronotype, sleep, and perceived exertion during intermittent fasting in young athletes

During intermittent fasting of Ramadan, research has shown a modification in athletes’ sleep habits and lifestyle. As a result, these changes might affect a range of chronobiological and psychological parameters. Thus, the present study explores the effect of intermittent fasting during Ramadan and circadian preference on sleep patterns and perception after aerobic exercise. This study included ninety-six active students (16.94 ± 1.09 years, BMI: 21.59 ± 3.52kg/m2). We identified the circadian preferences by exploiting Morningness-Eveningness Questionnaire (MEQ). Then we assess the perceived exertion at three-point times by using Rating of perceived exertion scale (RPE) after an aerobic exercise. At the end of Ramadan, we assess the sleep quality by using The Pittsburgh Sleep Quality Index (PSQI). Our analysis revealed that perceived exertion increased significantly during the three-time points, but sleep quality and maximal oxygen uptake decreased. Also, the results showed a significant association between chronotype and perceived exertion during Ramadan. Moreover, a meaningful prediction was detected of maximal oxygen uptake from BMI and perceived exertion. The main conclusion is that intermittent fasting affects sleep patterns, perceived exertion, and aerobic performance.

PERSIST: A Multimodal Dataset for the Prediction of Perceived Exertion during Resistance Training

Measuring and adjusting the training load is essential in resistance training, as training overload can increase the risk of injuries. At the same time, too little load does not deliver the desired training effects. Usually, external load is quantified using objective measurements, such as lifted weight distributed across sets and repetitions per exercise. Internal training load is usually assessed using questionnaires or ratings of perceived exertion (RPE). A standard RPE scale is the Borg scale, which ranges from 6 (no exertion) to 20 (the highest exertion ever experienced). Researchers have investigated predicting RPE for different sports using sensor modalities and machine learning methods, such as Support Vector Regression or Random Forests. This paper presents PERSIST, a novel dataset for predicting PERceived exertion during reSIStance Training. We recorded multiple sensor modalities simultaneously, including inertial measurement units (IMU), electrocardiography (ECG), and motion capture (MoCap). The MoCap data has been synchronized to the IMU and ECG data. We also provide heart rate variability (HRV) parameters obtained from the ECG signal. Our dataset contains data from twelve young and healthy male participants with at least one year of resistance training experience. Subjects performed twelve sets of squats on a Flywheel platform with twelve repetitions per set. After each set, subjects reported their current RPE. We chose the squat exercise as it involves the largest muscle group. This paper demonstrates how to access the dataset. We further present an exploratory data analysis and show how researchers can use IMU and ECG data to predict perceived exertion.

Effect of attentional focus on squats on lactate production and rating of perceived exertion in trained men

The aim of this study was to investigate the effect of internal focus (IF) and external focus (EF) on lactate production and the perception of perceived exertion in the squat in strength trained-men. Methods: Thirteen men with experience in strength training (age =22.61 ± 1.19 years; height = 180 ± 6.55 cm; body mass = 79.38 ± 5.57 kg; BMI = 24.56 ± 2.11 kg·m-2; Squat = 129 ± 20 kg) performed two sessions, separated by one week, comprising 3 sets of 10 repetitions of the back squat with one minute of rest between sets. During the IF protocol participants were instructed to focus on tightening the quads during all repetitions, while participants in the EF were instructed to focus on lifting the barbell. Blood lactate samples were collected before and at immediately after each of the 3 sets, as well as 15 minutes after the last set. Additionally, the rating of perceived exertion (RPE) was evaluated using the OMNI-RES scale immediately after the completion of each session. Results: Significant increases were found in the IF protocol at the end of each of the 3 sets, with significant effect sizes (1ª set, P= .000, d= 2.66; 2ª set, P= .000; d= 3.14; 3ª set, P= .000, d= 3.50), as in the EF protocol (1ª set, P= .001, d= 2.24; 2ª set, P= .000, d= 3.35; 3ª set, P= .000; d= 3.67). However, there were no significant inter-group differences between pre and any set (1ª set, P=0.951, d=0.03; 2ª set, P=0.239, d=0.47; 3ª set, P=0.435, d=0.31, respectively). Additionally, the perceptions on the RPE scale were higher in the FI (P= 0.032; d = 0.47). Conclusions: Findings suggest that the application of IF may indirectly contribute to muscle hypertrophy in multi-joint lower limb exercises, due to the increase in RPE values and the existing correlation with lactate production. Keywords: Mind-muscle, muscle hypertrophy, internal focus, mind-muscle connection, resistance training

Perceived Exertion: Revisiting the History and Updating the Neurophysiology and the Practical Applications.

The perceived exertion construct creation is a landmark in exercise physiology and sport science. Obtaining perceived exertion is relatively easy, but practitioners often neglect some critical methodological issues in its assessment. Furthermore, the perceived exertion definition, neurophysiological basis, and practical applications have evolved since the perceived exertion construct's inception. Therefore, we revisit the careful work devoted by Gunnar Borg with psychophysical methods to develop the perceived exertion construct, which resulted in the creation of two scales: the rating of perceived exertion (RPE) and the category-ratio 10 (CR10). We discuss a contemporary definition that considers perceived exertion as a conscious perception of how hard, heavy, and strenuous the exercise is, according to the sense of effort to command the limbs and the feeling of heavy breathing (respiratory effort). Thus, other exercise-evoked sensations would not hinder the reported perceived exertion. We then describe the neurophysiological mechanisms involved in the perceived exertion genesis during exercise, including the influence of the peripheral feedback from the skeletal muscles and the cardiorespiratory system (i.e., afferent feedback) and the influence of efferent copies from the motor command and respiratory drive (i.e., corollary discharges), as well as the interaction between them. We highlight essential details practitioners should consider when using the RPE and CR10 scales, such as the perceived exertion definition, the original scales utilization, and the descriptors anchoring process. Finally, we present how practitioners can use perceived exertion to assess cardiorespiratory fitness, individualize exercise intensity prescription, predict endurance exercise performance, and monitor athletes' responses to physical training.

Development and validation of a 1-km cardio-trekking test to estimate cardiorespiratory fitness in healthy adults

Maximum oxygen uptake (V̇O2max), the gold standard measure of cardiorespiratory fitness (CRF), supports cardiovascular risk assessment and is mainly assessed during maximal spiroergometry. However, for field use, submaximal exercise tests might be appropriate and feasible. There have been no studies attempting a submaximal test protocol involving uphill hiking. This study aimed to develop and validate a 1-km cardio-trekking test (CTT) controlled by heart rate monitoring and Borg’s 6–20 rating of perceived exertion (RPE) scale to predict V̇O2max outdoors. Healthy participants performed a maximal incremental treadmill walking laboratory test and a submaximal 1-km CTT on mountain trails in Austria and Germany, and V̇O2max was assessed with a portable spirometry device. Borg’s RPE scale was used to control the exercise intensity of the CTT. All subjects wore a chest strap to measure heart rate (HR). A total of 134 participants (median age: 56.0 years [IQR: 51.8–63.0], 43.3 % males) completed both testing protocols. The prediction model is based on age, gender, smoking status, weight, mean HR, altitude difference, duration, and the interaction between age and duration (R2 = 0.65, adj. R2 = 0.63). Leave-one-out cross-validation revealed small shrinkage in predictive accuracy (R2 = 0.59) compared to the original model. Submaximal exercise testing using uphill hiking allows for practical estimation of V̇O2max in healthy adults. This method may allow people to engage in physical activity while monitoring their CRF to avert unnecessary cardiovascular events.