Prescribing Exercise Intensity 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.

PRO-FIT-CARE study: the feasibility assessment of a pilot online exercise intervention for persons living with obesity and female infertility.

Moderate-to-high physical activity participation is associated with a reduced risk of infertility. Yet, exercise interventions that target cardiorespiratory fitness, independent of weight loss, are lacking in obesity and female fertility research. The primary objective of the PRO-FIT-CARE (PROmoting FITness for CArdiometabolic & REproductive Health) study was to assess the feasibility of a moderate-to-high-intensity online exercise program for persons with obesity and female infertility. Feasibility, safety, acceptability, and efficacy were assessed by examining: (1) recruitment and consent rate, (2) study retention, (3) adverse events, (4) participant satisfaction, (5) adherence, and (6) cardiorespiratory fitness. Eleven of thirty-two women contacted agreed to participate in the program (34.4% consent rate). Eight participants (72.7%) completed the study. One musculoskeletal injury was reported. There was a 30% adherence rate based on prescribed exercise intensity (60%-80% of heart rate maximum). One of eleven participants attended 80% of the exercise intervention. Based on a weekly satisfaction survey, the program had an overall high level of satisfaction. Compared to sex and age normative data, post-intervention, two of eight participants improved their cardiorespiratory fitness percentile rank. The study highlights challenges with adherence to an online exercise program. While the program was safe and participants reported high levels of program satisfaction, approaches to improve adherence must be incorporated.

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.

The effect of chronotropic incompetence on physiologic responses during progressive exercise in people with Parkinson's disease.

Heart rate (HR) response is likely to vary in people with Parkinson's disease (PD), particularly for those with chronotropic incompetence (CI). This study explores the impact of CI on HR and metabolic responses during cardiopulmonary exercise test (CPET) in people with PD, and its implications for exercise intensity prescription. Twenty-eight participants with mild PD and seventeen healthy controls underwent CPET to identify the presence or absence of CI. HR and metabolic responses were measured at submaximal (first (VT1) and second (VT2) ventilatory thresholds), and at peak exercise. Main outcome measures were HR, oxygen consumption (VO2), and changes in HR responses (HR/WR slope) to an increase in exercise demand. CI was present in 13 (46%) PD participants (PDCI), who during CPET, exhibited blunted HR responses compared to controls and PD non-CI beyond 60% of maximal workload (p ≤ 0.05). PDCI presented a significantly lower HR at VT2, and peak exercise compared to PD non-CI and controls (p ≤ 0.001). VO2 was significantly lower in PDCI than PD non-CI and controls at VT2 (p = 0.003 and p = 0.036, respectively) and at peak exercise (p = 0.001 and p = 0.023, respectively). Although poorly understood, the presence of CI in PD and its effect on HR and metabolic responses during incremental exercise is significant and important to consider when programming aerobic exercises.

A comparison of physiological and perceptual responses to fixed‐power and perceptually regulated cycling with and without blood flow restriction in trained cyclists

AbstractThis study compared physiological and perceptual responses between cycling prescribed using fixed‐power (PWR) and fixed rating of perceived exertion (RPE), when performed with blood flow restricted (BFRPWR and BFRRPE) and unrestricted (CONPWR and CONRPE). Endurance cyclists/triathletes cycled for 10 min in four separate randomized conditions; that is, two methods of prescribed exercise intensity (power at the first ventilatory threshold or RPE matched to CONPWR) combined with two occlusion levels (with BFR or without). Cardiorespiratory and perceptual variables were recorded every 2 min. Blood lactate concentration was measured pre‐, immediately and 2‐min postexercise. Power output during BFRRPE was lower than CONRPE (−13 ± 13%). The greatest physiological and perceptual responses were achieved during BFRPWR. Heart rate during BFRRPE was not different compared with CONPWR, yet was greater than CONRPE (+4 ± 11%). Muscular discomfort during BFRRPE was greater than CONPWR (+43 ± 18%) and CONRPE (+65 ± 58%). Cuff pain was greater during BFRPWR than BFRRPE (+14 ± 21%). Blood lactate concentration was not different between BFRRPE, CONPWR, and CONRPE at any timepoint. The reduction in power (fixed‐RPE trials; BFR minus unrestricted) correlated with changes in the respiratory rate (r = 0.85, confidence intervals [CI] = 0.51, 0.96) and postexercise lactate (r = 0.75, CI = 0.27, 0.93) but not muscular discomfort (r = 0.18, CI = −0.47, 0.71). Cardiorespiratory and metabolic stress, muscular discomfort, and cuff pain likely mediated self‐regulating fixed‐RPE cycling with BFR. While cycling with BFR at a fixed‐RPE resulted in less physiological stress compared to BFRPWR, it still provided a heightened level of physiological stress, with less pain and discomfort. As such, fixed‐RPE can be a suitable alternative for prescribing BFR to trained cyclists.

Heavy-, Severe-, and Extreme-, but Not Moderate-Intensity Exercise Increase V̇o 2max and Thresholds after 6 wk of Training.

This study assessed the effect of individualized, domain-based exercise intensity prescription on changes in maximal oxygen uptake (V̇O 2max ) and submaximal thresholds. Eighty-four young healthy participants (42 females, 42 males) were randomly assigned to six age, sex, and V̇O 2max -matched groups (14 participants each). Groups performed continuous cycling in the 1) moderate (MOD), 2) lower heavy (HVY1), and 3) upper heavy-intensity (HVY2) domain; interval cycling in the form of 4) high-intensity interval training (HIIT) in the severe-intensity domain, or 5) sprint-interval training (SIT) in the extreme-intensity domain; or no exercise for 6) control (CON). All training groups, except SIT, were work-matched. Training participants completed three sessions per week for 6 wk with physiological evaluations performed at PRE, MID, and POST intervention. Compared with the change in V̇O 2max (∆V̇O 2max ) in CON (0.1 ± 1.2 mL·kg -1 ·min -1 ), all training groups, except MOD (1.8 ± 2.7 mL·kg -1 ·min -1 ), demonstrated a significant increase ( P < 0.05). HIIT produced the highest increase (6.2 ± 2.8 mL·kg -1 ·min -1 ) followed by HVY2 (5.4 ± 2.3 mL·kg -1 ·min -1 ), SIT (4.7 ± 2.3 mL·kg -1 ·min -1 ), and HVY1 (3.3 ± 2.4 mL·kg -1 ·min -1 ), respectively. The ΔPO at the estimated lactate threshold ( θLT ) was similar across HVY1, HVY2, HIIT, and SIT, which were all greater than CON ( P < 0.05). The ΔV̇O 2 and ΔPO at θLT for MOD was not different from CON ( P > 0.05). HIIT produced the highest ΔPO at maximal metabolic steady state, which was greater than CON, MOD, and SIT ( P < 0.05). This study demonstrated that i) exercise intensity is a key component determining changes in V̇O 2max and submaximal thresholds and ii) exercise intensity domain-based prescription allows for a homogenous metabolic stimulus across individuals.

The Nostrum to Exercise: How Self-Selected and Imposed Exercise Intensity Prescription Relates to Affective, Cognitive, and Behavioral Outcomes - A Systematic Review

Allowing to select the exercise intensity has been proposed as a method to support exercise adherence, but no extensive exploration was found contrasting this approach to an imposed intensity method. For this matter, this systematic review aimed to explore the relationship between self-selected exercise intensity and affective, cognitive, and behavioral outcomes in physical activity settings, and whenever possible, compare this approach to other forms of exercise intensity prescription. Search was conducted in the PubMed, SPORTDiscus, and PsycINFO databases (last search date July 2022) with the following inclusion criteria: (1) experimental and non-experimental; (2) published in a peer-reviewed journal; (3) written in English; (4) exploring intensity self-selection and/or self-regulation in exercise settings; (5) samples with individuals aged between 18 and 64 years; and (6) focused on apparently healthy individuals. Twenty-nine studies (N=749 participants) were included in this review, 25 exploring aerobic exercise and four resistance training activities. Overall, self-selected exercise intensity showed better positive affective, cognitive, and behavioral outcomes compared to imposed exercise intensity prescription, but high heterogeneity on the methods and outcomes warrant caution when interpreting the results. Self-selected intensity may promote improved affective responses, autonomy perceptions, self-efficacy, intention to be physically active, and more minutes of exercise participation. However, discrepancy on the intensity self-selection methods, exercise protocol differences, and samples characteristics, highlight the need for further studies on the topic to better understand the possible magnitude of this effect. Permitir seleccionar la intensidad del ejercicio se ha propuesto como un método para apoyar la adherencia al ejercicio, pero no se encontró ninguna exploración extensa que contrastara este enfoque con un método de intensidad impuesta. Esta revisión sistemática explora la relación entre la intensidad del ejercicio seleccionada por el usuario y los resultados afectivos, cognitivos y conductuales en contextos de actividad física. La búsqueda se realizó en las bases de datos PubMed, SPORTDiscus y PsycINFO con los criterios de inclusión: (1) experimentales y no experimentales; (2) publicados en una revista revisada por pares; (3) escritos en inglés; (4) que exploraran la autoselección de intensidad y/o la autorregulación en contextos de ejercicio; (5) muestras con individuos de entre 18 y 64 años; y (6) centrados en individuos aparentemente sanos. Veintinueve estudios (N=749 participantes) fueron incluidos para revisión, 25 explorando el ejercicio aeróbico y cuatro de resistencia. En general, la intensidad de ejercicio autoseleccionada mostró mejores resultados afectivos, cognitivos y conductuales positivos en comparación con la prescripción de intensidad de ejercicio impuesta, pero la alta heterogeneidad en los métodos y resultados justifica la precaución al interpretar los resultados. La autoselección de la intensidad puede promover la mejora de las respuestas afectivas, las percepciones de autonomía, la autoeficacia, la intención de ser físicamente activo, y más minutos de participación en el ejercicio. Las discrepancias en los métodos de autoselección de la intensidad, las diferencias en los protocolos de ejercicio y las características de las muestras ponen de manifiesto la necesidad de realizar más estudios. Permitir a seleção da intensidade do exercício tem sido proposto como um método para apoiar a adesão ao exercício, mas não foi encontrada nenhuma exploração extensiva que contrastasse esta abordagem com um método de intensidade imposta. Por esta razão, esta revisão sistemática teve como objetivo explorar a relação entre a intensidade do exercício autosselecionada e os resultados afetivos, cognitivos e comportamentais em contextos de atividade física e, sempre que possível, comparar esta abordagem com outras formas de prescrição da intensidade do exercício. A pesquisa foi realizada nas bases de dados PubMed, SPORTDiscus e PsycINFO (última data de pesquisa em julho de 2022) com os seguintes critérios de inclusão: (1) experimentais e não-experimentais; (2) publicados numa revista com revisão por pares; (3) escritos em inglês; (4) que explorassem a autosseleção da intensidade e/ou a autorregulação em contextos de exercício; (5) amostras com indivíduos com idades compreendidas entre os 18 e os 64 anos; e (6) focados em indivíduos aparentemente saudáveis. Vinte e nove estudos (N=749 participantes) foram incluídos nesta revisão, 25 explorando o exercício aeróbico e quatro atividades de treino de resistência. Em geral, a intensidade de exercício autosselecionada mostrou melhores resultados positivos a nível afetivo, cognitivo e comportamental em comparação com a prescrição de intensidade de exercício imposta, mas a elevada heterogeneidade dos métodos e dos resultados justifica cautela na interpretação dos resultados. A intensidade autosselecionada pode promover melhores respostas afetivas, perceções de autonomia, autoeficácia, intenção de ser fisicamente ativo e mais minutos de participação no exercício. No entanto, a discrepância entre os métodos de autosseleção da intensidade, as diferenças entre os protocolos de exercício e as características das amostras, realçam a necessidade de mais estudos sobre o tema para melhor compreender a possível magnitude deste efeito.

Innovative and disruptive technologies to prescribe, encourage, and evaluate physical exercise in healthy adults: a protocol of exploratory study followed by a noninferiority, investigator-blinded randomized clinical trial

BackgroundCardiovascular diseases are a leading cause of mortality worldwide. A significant contributing factor to this mortality is the lack of engagement in preventive activities. Consequently, strategies for enhancing adherence to and duration of physical activity (PA) have become pivotal. This project aims to create and validate innovative, disruptive, and secure technologies that ensure appropriate exercise intensity, bolster adherence to PA, and monitor health biomarker responses pre-, during, and post-physical activity.MethodsThis exploratory study, followed by a noninferiority, investigator-blinded randomized clinical trial, will be divided into three phases: (1) development and validation of a sensor for real-time biofeedback during a functional assessment test; (2) integration of biofeedback and gamification into an app for the structured prescription of physical training within a controlled setting; and (3) implementation of biofeedback and gamification into an app for the prescription and monitoring of physical training in an uncontrolled setting. Phase 1 entails a validation test of a biosensor—monitoring heart rate (HR) and steps—during a modified shuttle walk test. In phase 2, the biosensor interfaces with a gamified smartphone application. The training regimen spans 6 weeks, 5 days weekly, with each session lasting 60 min: a five-min warm-up involving stationary gait, followed by 50 min of training at the target HR on the step and concluding with a five-min cool-down at a stationary pace. After 6 weeks of training, a new functional capacity test is conducted. Phase 3 involves an investigator-blinded, randomized clinical trial to demonstrate noninferiority. Participants are randomly assigned to either the intervention group (IG) or the control group (CG). IG participants practice exercise using the gamified application in an uncontrolled environment according to the prescribed method outlined in phase 2. CG participants receive PA practice guidelines exclusively.DiscussionAnticipated outcomes include improved exercise adherence through the gamified application, better maintenance of prescribed exercise intensity, and enhanced health biomarkers. The results of this study will inform health-related decision-making.Trial registrationThe study protocol received approval from the Ethics Committee of Universidade Federal de Ciências da Saúde de Porto Alegre (54,492,221.80000.5345) and has been registered with the Brazilian Registry of Clinical Trials (ReBEC, RBR-359p69v).

P102 Development of an easily applicable exercise test for exercise intensity prescription in neuromuscular diseases

P102 Development of an easily applicable exercise test for exercise intensity prescription in neuromuscular diseases

Novel Approach to Intradialytic Progressive Resistance Exercise Training

Physical activity levels are typically undesirably low in chronic kidney disease patients, especially in those undergoing haemodialysis, and particularly on dialysis days. Intradialytic exercise programmes could be a solution to this issue and have been reported to be safe and relatively easily implemented in dialysis clinics. Nevertheless, such implementation has been failing in part due to barriers such as the lack of funding, qualified personnel, equipment, and patient motivation. Intradialytic aerobic exercise has been the most used type of intervention in dialysis clinics. However, resistance exercise may be superior in eliciting potential benefits on indicators of muscle strength and mass. Yet, few intradialytic exercise programmes have focused on this type of intervention, and the ones which have report inconsistent benefits, diverging on prescribed exercise intensity, absent or subjective load progression, equipment availability, or exercise supervision. Commonly, intradialytic resistance exercise interventions use free weights, ankle cuffs, or elastic bands which hinder load progression and exercise intensity monitoring. Here, we introduce a recently developed intradialytic resistance exercise device and propose an accompanying innovative resistance exercise training protocol which aims to improve the quality of resistance exercise interventions within dialysis treatment sessions.

A Single Test Protocol to Establish the Full Spectrum of Exercise Intensity Prescription.

We aimed to test the extended capabilities of the SRS protocol by validating its capacity to predict the power outputs for targeted metabolic rates (V̇O 2 ) and time-to-task failure ( Tlim ) within the heavy- and severe-intensity domain, respectively. Fourteen young individuals completed (i) an SRS protocol from which the power outputs at GET and RCP (RCP CORR ), and the work accruable above RCP CORR , defined as W ' RAMP , were derived; (ii) one heavy-intensity bout at a power output predicted to elicit a targeted V̇O 2 equidistant from GET and RCP; and (iii) four severe-intensity trials at power outputs predicted to elicit targeted Tlim at minutes 2.5, 5, 10, and 13. These severe-intensity trials were also used to compute the constant-load-derived critical power and W ´ ( W ' CONSTANT ). Targeted (2.41 ± 0.52 L·min -1 ) and measured (2.43 ± 0.52 L·min -1 ) V̇O 2 at the identified heavy-intensity power output (162 ± 43 W) were not different ( P = 0.71) and substantially concordant (CCC = 0.95). Likewise, targeted and measured Tlim for the four identified severe-intensity power outputs were not different ( P > 0.05), and the aggregated coefficient of variation was 10.7% ± 8.9%. The derived power outputs at RCP CORR (192 ± 53 W) and critical power (193 ± 53 W) were not different ( P = 0.65) and highly concordant (CCC = 0.99). There were also no differences between W ' RAMP and W ' CONSTANT ( P = 0.51). The SRS protocol can accurately predict power outputs to elicit discrete metabolic rates and exercise durations, thus providing, with time efficiency, a high precision for the control of the metabolic stimulus during exercise.

The talk test as a useful tool to monitor aerobic exercise intensity in healthy population.

The talk test (TT) is subjective method to measure exercise intensity in costless and feasible manner, compared to sophisticated laboratory equipment. We attempted to investigate whether the TT was a valid method for evaluation of exercise intensity, by comparing with values derived from various physiologic markers during cardiopulmonary exercise testing on treadmill in healthy population. A total of 17 healthy subjects (12 males and 5 females) participated in this study. The TT was applied, which consisted of 3-stages difficulties demanding respiratory load while they performed the cardiopulmonary exercise testing on treadmill. In each of the TT stages, ergospirometric and psychophysiologic response marker were collected such as heart rate, oxygen consumption, respiratory exchange ratio, minute ventilation, carbon dioxide output, tidal volume, respiratory rate, and rating of perceived exertion of breathing. Statistical analyses revealed a significant difference of all dependent variables in each of three TT stages, comparing with the resting phase before the TT. The TT showed strong correlation coefficient with all variables except for rating of perceived exertion during the resting phase before the TT. According to increase of exercise intensity, all dependent variables showed a linear tendency with the stages of the TT. Our findings indicated that each of the TT stages was strongly correlated with ergospirometric variables as well as psychophysiologic response during cardiopulmonary exercise testing on treadmill. We suggested that the TT can be used to evaluate and prescribe exercise intensity of aerobic activity in cardiovascular and pulmonary rehabilitation settings.

Among Patients Taking Beta-Adrenergic Blockade Therapy, Use Measured (Not Predicted) Maximal Heart Rate to Calculate a Target Heart Rate for Cardiac Rehabilitation.

Among patients in cardiac rehabilitation (CR) on beta-adrenergic blockade (βB) therapy, this study describes the frequency for which target heart rate (THR) values computed using a predicted maximal heart rate (HR max ), correspond to a THR computed using a measured HR max in the guideline-based heart rate reserve (HR reserve ) method. Before CR, patients completed a cardiopulmonary exercise test to measure HR max , with the data used to determine THR via the HR reserve method. Additionally, predicted HR max was computed for all patients using the 220 - age equation and two disease-specific equations, with the predicted values used to calculate THR via the straight percent and HR reserve methods. The THR was also computed using resting heart rate (HR) +20 and +30 bpm. Mean predicted HR max using the 220 - age equation (161 ± 11 bpm) and the disease-specific equations (123 ± 9 bpm) differed ( P < .001) from measured HR max (133 ± 21 bpm). Also, THR computed using predicted HR max resulted in values that were infrequently within the guideline-based HR reserve range calculated using measured HR max . Specifically, 0 to ≤61% of patients would have had an exercise training HR that fell within the guideline-based range of 50-80% of measured HR reserve . Use of standing resting HR +20 or +30 bpm would have resulted in 100% and 48%, respectively, of patients exercising below 50% of HR reserve . A THR computed using either predicted HR max or resting HR +20 or +30 bpm seldom results in a prescribed exercise intensity that is consistent with guideline recommendations for patients in CR.

Exercise prescription to patients with cardiovascular disease is in greater agreement with ESC/EAPC recommendations after using the EXPERT Training tool

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by the Flemish Research Fund (FWO, FWO-ICA: G0F4220N). Background Exercise prescriptions by clinicians to patients with cardiovascular disease (CVD) often disagree with recommendations, thus requiring improvement. Aim To assess whether exercise prescriptions by clinicians to patients with CVD are better in agreement with ESC/EAPC recommendations when the EXPERT Training tool is used for digital training. Design: Prospective non-randomized intervention study. Methods Twenty-three Belgian physiotherapists first prescribed exercise intensity, frequency, session duration, program duration and exercise type (endurance or strength training) for the same three patient cases, from which the agreement with ESC/EAPC recommendations (based on a maximal score of 60/per case: agreement score) was assessed. Next, they completed a one-month digital training by using the EXPERT Training tool and completed 31±13 (out of 45 available) training cases. Thereafter, the same three patient cases as at entry of study were filled out again, with re-assessment of level of agreement with ESC/EAPC recommendations. Results After using the EXPERT Training tool the clinicians’ prescribed significantly greater exercise frequencies, program durations and total exercise volumes in all three patient cases (p&amp;lt;0.05). In case 1, 2 and 3, the agreement score increased from 29±9 (out of 60) to 41±9, from 28±9 to 41±10, and from 34±7 to 45±8, respectively (p&amp;lt;0.001). Hence, the total agreement score increased from 91±17 (out of 180) to 127±19 (p&amp;lt;0.001, +44±32%). A lower starting agreement score and younger age correlated significantly with a greater improvement in total agreement score (p&amp;lt;0.05). Conclusions Exercise prescriptions to patients with CVD, generated by clinicians, are significantly better in agreement with ESC/EAPC recommendations when the EXPERT Training tool is used.

The effects of high-intensity interval training and moderate-to-vigorous intensity on cardiorespiratory fitness in patients with permanent or persistent atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): the Innovations Fund of the Alternate Funding Plan for the Academic Health Sciences Centre of the Ministry of Ontario. Background Lower cardiorespiratory fitness (CRF) in atrial fibrillation (AF) is associated with higher risk of mortality. Moderate-to-vigorous intensity continuous training (MICT) increases CRF; however, growing evidence indicates that high-intensity interval training (HIIT) elicits similar or greater improvements in CRF in people with cardiovascular disease. Purposes The purposes of this study were to: (1) compare the effects of HIIT and MICT on CRF in patients with persistent and permanent AF; and, (2) assess the proportion of participants who achieved a clinically meaningful increase in CRF (i.e., 3.5 mL/kg/min, associated with significant reduction in mortality in AF). Methods This was a subanalysis of an RCT to examine the effects of HIIT and MICT on functional capacity. Participants completed cardiopulmonary exercise test (CPET) and were randomly assigned to 12-week, twice weekly supervised HIIT or MICT. Each HIIT session was 23 min in duration, completed on a stationary bike, and consisted of: (1) a 2-min warm up; (2) two blocks of 8 x 30-sec high-intensity work periods at 80-100% peak power output interspersed with 30-sec active recovery periods, with 4 min active recovery between the blocks; and, a 1-min cooldown. Each MICT session consisted of (1) a 15-min warm up; (2) 30-min of continuous aerobic exercise; and, (3) a 15-min cooldown. A subset of willing participants completed follow-up CPET. Repeated measures ANOVA was used to compare the changes in CRF between HIIT and MICT. Descriptive statistics was used to assess the proportion of patients meeting the clinically meaningful increase in CRF. Results Of 94 patients consented, 13 in HIIT (67±4 years old, 26% females) and 10 in MICT (71±9 years old, 40% females) completed pre and post CPET. Exercise adherence (i.e., % of sessions attended) was 91% for HIIT and 85% for MICT, respectively, and did not differ between the groups. At week 12, 76% of participants in HIIT and 80% in MICT achieved the prescribed exercise intensity targets. Our per-protocol analysis showed no overall change in CRF (pre: 19.0±5.1 vs. post: 19.4±4.6 mL/kg/min, p=0.461). No significant differences in changes in CRF were observed between HIIT (pre: 20.1±5.3 vs. post: 20.3±4.5 mL/kg/min) and MICT (pre: 17.6±4.8 vs. post: 18.4±4.7 mL/kg/min, interaction effect p=0.681). Two participants in HIIT (15.4%) and two in MICT (20.0%) achieved clinically meaningful increases. Conclusions Twice weekly HIIT or MICT for 12 weeks did not improve CRF in patients with persistent and permanent AF who completed CPET. Further, a small proportion of these patients (≤ 20%) achieved clinically meaningful increase in CRF. Considering a greater increase in CRF (3.2±2.5 mL/kg/min) in patients with non-permanent AF following high-volume HIIT (a total of 16 min at high intensity per session, three times per week) in a previous RCT, a larger exercise volume may be required to improve the CRF of patients with persistent and permanent AF.

PE-452787-1 THE RELATIONSHIP BETWEEN VENTILATORY ANAEROBIC THRESHOLD AND ARRHYTHMIA ONSET IN PATIENTS WITH CATECHOLAMINERGIC VENTRICULAR TACHYCARDIA

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a genetic disease associated with malignant ventricular arrhythmias, typically developing at high heart rate (HR) and catecholamine states. Patients are often restricted from exercise. Cardiopulmonary exercise testing (CPET) is used to diagnose and monitor patients to ensure HR-associated arrhythmias are adequately blunted on beta blockers (BB). In addition to peak HR, CPET can also determine the ventilatory anaerobic threshold (VAT), the point at which the body shifts from aerobic to anaerobic metabolism generating lactic acid as a byproduct. VAT is commonly used in prescribing exercise intensity in those with and without heart disease but has not been evaluated in CPVT patients. This transition point could be useful clinically in determining more precise exercise limits in patients with CPVT. To assess if there is an association between VAT and the development of arrhythmia during exercise in those diagnosed with CPVT. This is a retrospective cohort study on all patients with CPVT completing exercise testing at our institution from July 2017 through September 2022. VAT was calculated utilizing the V-slope method. Simple ectopy was defined as single, uniform premature ventricular complexes (PVCs) and complex ectopy defined as polymorphic PVCs or ventricular tachycardia. The HR at the time ventricular ectopy first developed was noted. There were 44 CPETs completed by 10 patients (19.8±10.4 years-old at first test; 50% male) with genetically-confirmed CPVT. Most tests occurred while the patient was on BB therapy (39/44). Patients had simple ectopy in 34 tests and complex ectopy in 25. No patients developed complex ectopy before VAT during any test (Figure 1). Average HR at VAT (101.4±14.7 bpm) was below both the HR at which simple (122.1±14.3 bpm) and complex (136.8±18.4 bpm) ectopy developed. Average HR at each point in exercise was lower in the group on BB than those not on a BB. These HR and arrhythmia trends were similar on the initial CPET at diagnosis and on their subsequent tests. Patients with CPVT seem to reach VAT prior to the onset of ventricular ectopy. Anaerobic metabolism may play a role in the arrhythmogenicity of these patients, possibly due to lactic acid production. If confirmed in larger studies, activity restrictions could be liberalized to allow low-intensity exercise below the VAT with precise HR goals in patients with CPVT.

Conventional methods to prescribe exercise intensity are ineffective for exhaustive interval training

PurposeTo compare methods of relative intensity prescription for their ability to normalise performance (i.e., time to exhaustion), physiological, and perceptual responses to high-intensity interval training (HIIT) between individuals.MethodsSixteen male and two female cyclists (age: 38 ± 11 years, height: 177 ± 7 cm, body mass: 71.6 ± 7.9 kg, maximal oxygen uptake ( dot{text{V}} O2max): 54.3 ± 8.9 ml·kg−1 min−1) initially undertook an incremental test to exhaustion, a 3 min all-out test, and a 20 min time-trial to determine prescription benchmarks. Then, four HIIT sessions (4 min on, 2 min off) were each performed to exhaustion at: the work rate associated with the gas exchange threshold ( dot{text{W}} GET) plus 70% of the difference between dot{text{W}} GET and the work rate associated with dot{text{V}} O2max; 85% of the maximal work rate of the incremental test (85% dot{text{W}} max); 120% of the mean work rate of the 20 min time-trial (120%TT); and the work rate predicted to expend, in 4 min, 80% of the work capacity above critical power. Acute HIIT responses were modelled with participant as a random effect to provide estimates of inter-individual variability.ResultsFor all dependent variables, the magnitude of inter-individual variability was high, and confidence intervals overlapped substantially, indicating that the relative intensity normalisation methods were similarly poor. Inter-individual coefficients of variation for time to exhaustion varied from 44.2% (85% dot{text{W}} max) to 59.1% (120%TT), making it difficult to predict acute HIIT responses for an individual.ConclusionThe present study suggests that the methods of intensity prescription investigated do not normalise acute responses to HIIT between individuals.

An evaluation of the role of the exercise training dose for changes in exercise capacity following a standard cardiac rehabilitation program

BackgroundTo retrospectively characterize and compare the dose of exercise training (ET) within a large cohort of patients demonstrating different levels of improvement in exercise capacity following a cardiac rehabilitation (CR) program. MethodsA total of 2310 patients who completed a 12-week, center-based, guidelines-informed CR program between January 2018 and December 2019 were included in the analysis. Peak metabolic equivalents (METpeak) were determined pre- and post-CR during which total duration (ET time) and intensity [percent of heart rate peak (%HRpeak)] of supervised ET were also obtained. Training responsiveness was quantified on the basis of changes in METpeak from pre- to post-CR. A cluster analysis was performed to identity clusters demonstrating discrete levels of responsiveness (i.e., negative, low, moderate, high, and very-high). These were compared for several baseline and ET-derived variables which were also included in a multivariable linear regression model. ResultsAt pre-CR, baseline METpeak was progressively lower with greater training responsiveness (F(4,2305) = 44.2, P < 0.01, η2p = 0.71). Likewise, average training duration (F(4,2305) = 10.7 P < 0.01, η2p = 0.02) and %HRpeak (F(4,2305) = 25.1 P < 0.01, η2p = 0.042) quantified during onsite ET sessions were progressively greater with greater training responsiveness. The multivariable linear regression model confirmed that baseline METpeak, training duration and intensity during ET, BMI, and age (P < 0.001) were significant predictors of METpeak post-CR. ConclusionsAlong with baseline METpeak, delta BMI, and age, the dose of ET (i.e., training duration and intensity) predicts METpeak at the conclusion of CR. A re-evaluation of current approaches for exercise intensity prescription is recommended to extend the benefits of completing CR to all patients.

Dissonance in views between healthcare professionals and adults with a spinal cord injury with their understanding and interpretation of exercise intensity for exercise prescription

ObjectivesTo evaluate the difference between healthcare professionals (HCPs) and adults with spinal cord injury (SCI) in Asia regarding knowledge and interpretation of ‘exercise intensity’ for aerobic exercise prescription.Methods and study...

Exercise prescription by physiotherapists to patients with cardiovascular disease is in greater agreement with European recommendations after using the EXPERT training tool

ABSTRACT Background Exercise prescriptions by clinicians to patients with cardiovascular disease (CVD) often disagree with recommendations, thus requiring improvement. Aim To assess whether exercise prescriptions by physiotherapists to patients with CVD are better in agreement with European (ESC/EAPC) recommendations when the EXPERT (EXercise Prescription in Everyday practice & Rehabilitative Training) Training tool is used for digital educational training. Design In a prospective non-randomized intervention study. Methods Twenty-three belgian physiotherapists first prescribed exercise intensity, frequency, session duration, program duration and exercise type (endurance or strength training) for the same three patient cases, from which the agreement with ESC/EAPC recommendations (based on a maximal score of 60/per case: agreement score) was assessed. Next, they completed a one-month digital training by using the EXPERT Training tool and completed 31 ± 13 training cases. The EXPERT tool is a training and decision support system that automatically generates a (personalised) exercise prescription according to the patient’s characteristics, thus integrating the exercise prescriptions for different CVDs and risk factors, all based on ESC/EAPC recommendations. Thereafter, the same three patient cases as at entry of study were filled out again, with re-assessment of level of agreement with ESC/EAPC recommendations. Results After using the EXPERT Training tool, the physiotherapists prescribed significantly greater exercise frequencies, program durations and total exercise volumes in all three patient cases (p < 0.05). In cases 1, 2 and 3, the agreement score increased from 29 ± 9 (out of 60), 28 ± 9, and 34 ± 7 to 41 ± 9, 41 ± 10, and 45 ± 8, respectively (p < 0.001). Hence, the total agreement score increased from 91 ± 17 (out of 180) to 127 ± 19 (p < 0.001, +44 ± 32%). A lower starting agreement score and younger age correlated with a greater improvement in total agreement score (p < 0.05). Conclusions Exercise prescriptions to patients with CVD, generated by physiotherapists, are significantly better in agreement with European recommendations when the EXPERT Training tool is used, indicating its educational potential.