The ratings of perceived exertion are commonly employed within both a clinical and exercise setting to quantify, monitor and evaluate an individual’s exercise tolerance and level of exertion. Recent advances in the area of perceived exertion have led to novel applications in the use of the ratings of perceived exertion scale as a means of predicting an individual’s maximal functional capacity (VO2max) for exercise (Eston, Lamb, Parfitt, & King, 2005; Eston, Faulkner, Mason, & Parfitt, 2006; Eston, Lambrick, Sheppard, & Parfitt, 2008; Faulkner, Parfitt, & Eston, 2007). Yet the utility of such procedures with low-fit individuals or children has received little or no research attention. As such, one aim of this thesis was to assess the efficacy of the ratings of perceived exertion in predicting the VO2max of low-fit men and women, and healthy children. It is often presumed that like adults, a child’s perception of exertion rises linearly with increases in exercise intensity, despite a limited amount research suggesting otherwise. Moreover, there is a lack of empirical evidence to suggest that children regulate their power output during a closed-loop exercise task in order to complete a given distance in the fastest time possible. Therefore, a further aim of this thesis was to explore the nature of the perceptual responses of young children across differing modes of exercise, and to examine whether children employ pacing strategies during running. In relation to this latter aim, it was of particular interest to explore pacing in relation to the ratings of perceived exertion during running, as the ratings of perceived exertion have been proposed as a key component of such a regulatory system during exercise (Tucker, 2009). This thesis comprises a qualitative review of relevant literature, and six study chapters which were borne out of five empirical studies. The findings of studies 1 and 2 (chapters 3 & 4, respectively) support the utility of the ratings of perceived exertion to estimate VO2max in low-fit men and women, during cycle ergometry exercise. Importantly, this has been shown from a single exercise test at a low-moderate exercise intensity, during either a step-incremental (study 1) or ramp-incremental (study 2) protocol. Studies 3 and 4 (chapters 5 & 6, respectively) provide evidence to suggest that a child’s perception of exertion may rise linearly or curvilinearly in relation to increasing work, during either cycle ergometry or treadmill exercise. These studies support the utility of a unique, curvilinear, paediatric ratings of perceived exertion scale in obtaining accurate exertional responses from young children, across differing modes of exercise. In contrast to studies 1 and 2, study 5 (chapter 7) suggests that the novel means of predicting maximal functional capacity from submaximal ratings of perceived exertion in adults is inaccurate with young children. This was particularly evident in the low intraclass correlation coefficients and wide limits of agreement obtained between measured- and predicted VO2max, for both cycle ergometry and treadmill exercise. Study 6 (chapter 8) demonstrated that young children employ pacing strategies during an 800 m run, similar to adults, and that this improves with trial familiarisation. Moreover, the presence of other competitors has a detrimental effect on performance, particularly for girls.

Planning a multi-day bicycle tour is a time intensive and difficult task. To enable cyclists to construct their own multi-day tour routes, we propose an automated system which, given an origin, destination, and points of interest, generates detailed bicycle tour routes of minimal perceived exertion. This dissertation is comprised of three bodies of work contained in chapters 2, 3, and 4, respectively. In the first work, chapter 2, we build and test a model of the perceived exertion of different categories of cyclists on a daily path within a long bicycle tour. We first propose an additive formula for calculating the perceived exertion of cyclists on component parts of a tour and then present the results of a survey designed to verify the accuracy of the model. In the second work, chapter 3, we describe an algorithmic procedure for transforming a traditional road graph into a topographical graph. To that end we use polyline data from the OpenStreetMap (OSM), elevation data from the U.S. Geological Survey, and a model of perceived exertion for bicyclists of different levels of expertise. Our topographical graph allows for the calculation of the perceived exertion over any sequence of road segments (a path) for bicyclists of different levels of expertise and serves as input for generating paths of minimal perceived exertion. In the final work, chapter 4, we describe a procedure for constructing bicycle routes of minimal perceived exertion for cyclists of different levels of expertise over a multi-day tour. Given a cyclists origin, destination, selected points of interest, and a level of cycling expertise, this procedure generates a multi-day bicycle tour as a collection of successive daily paths that begin and end at overnight accommodations. We demonstrate the implementation of this procedure on an example multi-day tour route in California and present the results of a survey designed to evaluate the daily paths constructed. In summation, this dissertation contributes a new metric of perceived exertion for bicycle riders, a new topographical graph, and a procedure for constructing multi-day bicycle tour routes of minimal perceived exertion for bicyclists of different levels of expertise.

Mental fatigue impairs performance of physically-demanding tasks and increases rating of perceived exertion (RPE) while performing. However, there may be ways of overcoming such performance decrements. One possible method includes the use of attentionally focused instructions. Motor learning research has shown that externally focused instructions can lead to improved performance in comparison to internally focused instructions. The purpose of the present study was to investigate the moderating effect of attentional focus on the mental fatigue – endurance performance relationship as well as the mental fatigue – perceived exertion relationship. Undergraduate students (N = 78) completed two wall sit tasks to volitional failure, one before and one after the completion of a cognitive task. Half the participants were randomly assigned to complete a high cognitive demand task to induce mental fatigue (incongruent Stroop; HMF), while the other half performed a low cognitive demand task (documentary viewing; LMF) before the second wall sit. Immediately prior to the second wall sit, half the participants in each cognitive task group also received instructions to focus their attention either internally (INT) or externally (EXT) during the second wall sit. The main effect of mental fatigue (p < .001, d = .873) during the cognitive task and the main effect of attentional focus (p < .001, d = .883) during the wall sit task were significant, indicating effective manipulations. Results found no moderating effect of attentional focus on wall sit performance (p >.500) or RPE (p = .724). However, between-group analyses were conducted to probe the differences in performance between each group. Results indicated the HMF/INT group performed significantly worse than the LMF/EXT (p = .032) and trended towards performing worse than the HMF/EXT and LMF/INT groups (ps < .090). Significant differences in RPE were also seen between trials for the HMF/INT group (p = .009, d = .592) alone, suggesting detrimental effects of both mental fatigue and internal focus combined. Overall, the data indicate a potential moderating effect of internal attentional focus that may exacerbate the detrimental effects of mental fatigue on performance and RPE. / Thesis / Master of Science (MSc)

In a 1994 survey, on incidence rates of musculoskeletal injuries among private industries within the U.S, nurses ranked first nationally. Patient handling tasks are considered to be a precipitating factor in the development of many musculoskeletal injuries. For many decades personnel training has been an intervention widely used for the nursing back problem. Inconsistency regarding the effectiveness of many personnel training programs, lack of controlled research among existing studies, and a primary focus only on long term reduction of injury rates makes the interpretation of the success of personnel training programs a difficult one. This study is based on the assumption that, if a training program is to be effective as a means of reducing musculoskeletal injuries, it must first modify worker behaviors and biomechanical stresses to a measurable degree. This research investigated the effects of training (Video and Lecture/Practice) on modifying working behaviors and biomechanical stress. Two tasks were examined (wheelchair to bed and lift up in bed) with two types of assistance (one-person or two-person) and two levels of patient's dependence (semi-dependent or dependent). Changes in behaviors were examined immediately following training (1-2 days delay) and after a short period of time (4-6 weeks) and evaluated using the criteria of subjective ratings of exertion, and postural and biomechanical measures. Results indicated that training led to several significant changes in the knee, hip, elbow and torso angles, whole body, shoulders and low back RPE, shear forces and shoulder moments. No differences were observed in these measures after a short period of time, suggesting retention of the information presented during the training programs. Results as a whole suggest that training can positively affect the working postures and biomechanical stress during common patient handling tasks. All the postural changes and biomechanical measures were advantageous in terms of reducing musculoskeletal stress. It was also found that after a short period of time (4-6 weeks) still retained the information presented during the training programs. Training using a combination of lecture and practice in some cases achieved better results than Video-based training. / Master of Science

The Borg 6–20 rating of perceived exertion (RPE) scale is a common measure reported during exercise testing and training, and is usually taken as a response measurement to provide a subjective assessment of exercise intensity. A lesser used application of the scale is for regulating exercise intensity, referred to as its ‘production mode’. Recent research on this topic initiated by Eston et al. (2005) has led to a novel application of this procedure as a means of predicting an individual’s maximal oxygen uptake ( O2max) via a perceptually-regulated exercise test (PRET). The PRET could play a significant role in guiding exercise prescription and monitoring cardiorespiratory fitness levels in situations where the normal heart rate response is affected. The aim of this thesis is to develop further and test the integrity of the PRET technique. Firstly, a review of the evidence on the validity and reliability of the Borg RPE scale when used to regulate exercise intensity in healthy and unhealthy adults is presented, as to-date, no scholarly publication has synthesised the body of knowledge on this specific application of the scale. Subsequently, four studies were completed to investigate the effects of different methodological variations on the predictive capabilities of the PRET, including an examination (for the first time) of its utility among heart failure patients (Study 4). Study 1 re-visited the validity and reliability of the PRET technique utilising a modified protocol of differing durations (2 and 4 min bouts), with revised instructions and placing the graded exercise test (GXT) as the final trial during cycle ergometry. Superior results were observed to those reported in previous investigations (Eston et al., 2008; Faulkner et al. 2007; Eston et al., 2006) during the 3 min trial, further reinforcing the validity and reliability of this technique. Accordingly, Study 2 was the first to investigate the reliability and validity of a treadmill PRET protocol with a ceiling intensity of RPE 15, rather than RPE 17, and observed that a safer modified PRET (with practice) provides acceptably valid and reliable predictions of O2max in healthy adults. In addition, Study 3 extended the research thus far by investigating the PRET protocol during cycle exercise, once again with a ceiling intensity of RPE 15, and demonstrated that (with practice) a cycle-based PRET can yield reliable and valid predictions of O2max that compare favourably to previous investigations. Finally, given that the research employing a PRET has unanimously alluded to its likely value in clinical populations among whom heart rate as a physiological response to exercise is affected (e.g. via medication) and precluded as a means predicting O2max, Study 4 investigated the utility of a PRET in a beta-blocked population of heart failure patients. In the event, it was observed that a PRET (up to RPE 15) was too strenuous and needs to be capped at an intensity of RPE 13 in this population. In addition a continuous protocol seemed unsuitable due to its length and it was recommended that a discontinuous PRET protocol be investigated. Future research needs to investigate the utilisation of the PRET (i) in different exercise modes; (ii) determine the optimum number of practice trials required; (iii) whether a discontinuous or continuous protocol is more appropariate; (iv) whether the extrapolation should be made to RPE 19 or 20 and; (v) whether the PRET can be employed succesfully in other clinical populations.

The aim of this research programme was to investigate the effects of different music applications: The differentiated exposure of music and the synchronous application of music. In Study 1, participants completed a series of 10-km cycling time trials under four single-blinded conditions: No-music control, music 0-10 km (M1), music 0-5 km (M2), and music 5-10 km (M3). The largest performance gains were noticed under M1, followed by M3, when compared to control, while the most positive psychological response was observed only in M3. Study 2 further examined the notion of differentiated music exposure by incorporating both quantitative and qualitative modes of inquiry. In addition, participants were given foreknowledge of the experimental conditions. Although no performance gains were found across conditions, M3 significantly reduced perceived exertion and prevented affective decline. Qualitative findings suggest that prolonged exposure to music may have negative psychological and psychophysical consequences. The last study contrasted the effects of synchronous and asynchronous application of music in a 6-min submaximal cycling task. Synchronous music was more effective than asynchronous music in terms of reducing perceptions of exertion and increasing subjective arousal. Although no changes in oxygen uptake were found across conditions, auditory-motor synchronisation appeared to reduce heart rate. The contribution of this thesis is twofold. Firstly, the provision of music in the latter stages of a task appears to have significant psychological and psychophysical benefits when compared against constant music exposure. Secondly, more positive effects, in terms of perceived exertion and subjective arousal, are observed when music is applied synchronously compared to asynchronously; this suggests a need for a separate conceptual framework for the application of synchronous music.

Present day manufacturing assembly relies extensively on a variety of fasteners for the assembly of sub-systems, components and trim. Speed Fastening (SF) is one commonly used non-structural assembly fastening method. The primary limitation of SF is the lack of continuously fed rivets. One path to productivity improvement for SF is the development of a continuously feed tool that would eliminate the non-value added time currently scheduled for reloading in the work cycle. In preparation for the design of a new tool, a proactive ergonomic investigation was carried out to examine differences in muscular effort, upper-body posture, as well as subjective ratings of perceived exertion and discomfort across three different work rates for a simulated SF task conducted in a laboratory setting. The purpose of this investigation was to characterize the ergonomic consequences that an increase in work rate would have on SF operators. Twelve healthy female subjects participated in simulated SF work over four test-sessions. The first test session familiarized subjects with the SF tasks as well as the data collection protocol. Subsequent test days, which were scheduled 24 hours apart, were block randomized to one of three work rates (7, 14 and 21 fasteners/min.) with subjects required to complete 120 minutes of a simulated SF task at both waist and shoulder height using a 50% work to rest duty cycle. The results of this study show significant increases in the amount of muscular activity required to complete the simulated SF, particularly for the 21 fasteners per minute work rate, with increases in peak sEMG amplitudes ranging from 3-12% MVIC. Specifically these increases were most marked in the forearm extensor muscles. In addition, significantly deviated postures were found in upper-limb joint ROM data, particularly when SF work was completed at shoulder height. Overall, based on the increased exposure to risk factors known to be precursors for workplace injury (i.e. repetition and awkward posture), it is inferred that an increase in work rate will put SF operators at an elevated risk of musculoskeletal injury. It is expected that this risk would be even more pronounced for work completed at shoulder height. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2009-09-02 00:01:36.701

Nursing staff have an elevated risk of developing musculoskeletal disorders, in particular in the lower back area. Statistics produced by leading industrial nations show that back problems are the world’s number one work-related health problem, and that healthcare workers suffer from a greater occurrence of such problems than workers in other professions. In this context, many studies have examined manual patient handling activities, which was thought to be the main cause of musculoskeletal disorders of the lower back. But nurses have many other types of work to perform and several reviews have concluded that approaches which only focus on manual patient handling activities do not sufficiently reduce back problems in nursing professions. Other risk factors for musculoskeletal disorders of the lower back discussed in the literature included repeated bending and the high proportion of static trunk postures. The main aim of this doctoral thesis was therefore to examine the influence of stressful trunk postures on the physical workload of nursing staff in hospitals and nursing homes. It focuses on the type, number and extent of stressful postures and on identifying activities that encourage their occurrence. We used our findings to derive strategies for reducing stressful postures in nursing, and examined whether nursing staff regard such a reduction as actually relieving their physical workload. A secondary aim was to consider the older people potentially in need of care. The background to this is that, due to steadily rising costs, many older people are unable to afford care in a nursing home, and additionally that the forecast severe shortage of nursing staff in future gives reason to look for solutions that can reduce the demand for nursing staff. Among older people who still look after themselves, we therefore examined which stressful postures they adopt when carrying out domestic tasks such as cooking and washing laundry. From the results, we provided some examples of a better design of the domestic environment, which reduces stressful postures, when performing these tasks and helps older people to be able to look after themselves in their own homes for longer. / <p>QC 20140324</p>

Orientador: Antonio Carlos de Moraes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Educação Física / Made available in DSpace on 2018-08-18T17:14:16Z (GMT). No. of bitstreams: 1 Fontes_EduardoBodnariuc_D.pdf: 9503115 bytes, checksum: ace5f37f3ad02cc8337e62c4be60c8b2 (MD5) Previous issue date: 2011 / Resumo: O presente trabalho buscou um maior entendimento da formação da percepção subjetiva de esforço (PSE) durante esforços exaustivos. Dessa forma, o primeiro estudo verificou as associações da atividade muscular (EMG) com a PSE, bem como a determinação do limiar de esforço percebido (LEP) e de fadiga neuromuscular (LFN). Esse estudo analisou 11 adultos jovens durante testes de carga constante até a exaustão voluntária máxima com monitoramento constante de PSE e EMG. A taxa de aumento dessas variáveis (EMGslope e PSEslope) foram significativamente correlacionados e inversamente associados ao tempo de exaustão. LEP e LFN e não se diferiram significativamente. Assim, indicamos a estreita relação do recrutamento adicional de fibras com o aumento da PSE. O segundo estudo foi realizado durante estágio no exterior (sanduíche) na África do Sul no ano de 2009. Nesse trabalho, foi analisado os efeitos da diminuição de oferta de oxigênio (hipóxia) sobre variáveis centrais e periféricas e suas associações com PSE. Seis ciclistas realizaram testes exaustivos de carga constante em normoxia e hipóxia com contínua aquisição de respostas de PSE, EMG e oxigenação muscular (MOX) e cerebral (COX). Foi demonstrado que na condição hipóxia ocorre um significativo aumento sobre PSE em seus diferentes modos (local, respiração e geral), EMG e COX, mas não em MOX. Os slopes de PSE e valores finais de COX foram relacionados ao desempenho em normóxia, no entanto ainda maiores foram apresentados em hipóxia. Além disso, COX foi ainda significativamente relacionada RPE local em normóxia e novamente, hipóxia exerceu efeitos maiores nessas associações, mas dessa vez para todos os modos de PSE. No terceiro estudo, foram utilizado os mesmos dados do estudo anterior para verificamos os possíveis efeitos de hipóxia ao estimarmos LEP de maneira diferenciada (local, respiração e geral) e LFN pelo mesmo protocolo. Todos os modos de LEP diminuíram significativamente sob hipóxia, com maiores efeitos sobre LEP local. Já LFN não respondeu aos efeitos da condição experimental. Dessa forma, expandiu-se a utilização de LEP para altitudes moderadas e foi apresentado uma nova forma de predizer capacidade aeróbia referente aos membros envolvidos e respiração, além de PET para o corpo como um todo. Associando os achados dos estudos, podemos inferir a estreita relação de respostas periféricas e centrais sobre a formação de PSE, senda essas fortalecidas em condições de diminuídas ofertas de oxigênio. Mais adiante, essas associações justificam a ampliação de utilização prática de PSE, podendo ser para o exercício de alta intensidade ou monitoramento localizado da capacidade aeróbia / Abstract: The present study aimed to bring better understanding of ratings of perceived exertion (RPE) during exhaustive exercise. Thus, the first study verified the associations of the neuromuscular responses (EMG) with RPE, as well as the determination of the perceived exertion threshold (PET) and neuromuscular fatigue threshold (NFT). Eleven adults performed exhaustive constant-load tests with RPE and EMG recordings. The rate of increase of these variables (EMGslope e RPEslope) were significantly related and associated to performance. Além disso, PET and NFT did not differed. Therefore, it was shown the close relationship of the additional muscle recruitment and RPE. The second study was completed during the international internship in South Africa in 2009. At this investigation, were demonstrated the effects of decreased fraction of inspired oxygen (hypoxia) on central and peripheral responses, as well their relationship with RPE. Six trained cyclists completed exhaustive constant-load tests under normoxia and hypoxia having continuously monitoring of RPE, EMG and cerebral (COX) and muscle (MOX) oxygenation. It was shown that under hypoxia there is a significant increase for all RPE modes (legs, breathing and overall), EMG and COX, but not MOX. The RPE slopes and end values for COX were related to performance under normoxia, however higher associations were found under hypoxia. In addition, COX was significantly related to RPE for legs under normoxia, but again, hypoxia exert higher effects on this association, but this time to all RPE modes. During the third study, the data from last investigation was used to verify the possible effects of hypoxia when estimating differentiated PET (legs, breathing and overall) and NFT during same protocol. All PET modes decrease significantly under hypoxia, with higher effects of PET legs, however, NFT estimation was not affects by this experimental condition. Thus, PET's used was expanded to moderated altitudes and presented a new method to predict aerobic capacity associated to active limbs and breathing, in addition to whole body PET. Associating the studies' findings it is possible to conclude that there is a strict relationship of peripheral and central responses to RPE construct, being this sthrengthed by decreased oxygen availability. Furthermore, these relationship justifies the practical use RPE, as for prescription of high intensity exercise or localized monitoring of aerobic capacity / Doutorado / Ciencia do Desporto / Doutor em Educação Física

Perceived exertion is how hard or heavy an individual feels they are working. Perceived exertion is often quantified using the ratings of perceived exertion (RPE) scale and can be used to measure exercise intensity based on the experience of an individual. While objective methods of assessing exercise intensity, such as measurement of heart rate and percent of peak oxygen uptake, are useful, RPE is commonly implemented for the ease of use and feasibility. For example, RPE is commonly implemented in rehabilitation settings for people with a spinal cord injury and individuals with coronary artery disease because of their non-linear heart rate response to increases in exercise workload. The overarching purpose of this dissertation was to investigate a range of research questions designed to advance the knowledge and use of RPE guided exercise. Through a systematic review and meta-analysis, we examined evidence for the impact on cardiorespiratory fitness and peak power output using RPE-guided interventions in individuals with a spinal cord injury (SCI) and found that RPE-guided interventions improved both after a variety of exercise intervention types and lengths. In a separate retrospective cross-sectional analysis, we then demonstrated that perceived exertion, measured by leg cycling effort during a cardiopulmonary exercise test on a leg cycle ergometer in non-disabled individuals, was predicted by power and maximum power output. After further investigation we found that quadriceps strength predicted maximum power output and therefore is related to leg cycling effort. In the third study of the thesis, we conducted semi-structured interviews in individuals with an SCI and their healthcare practitioners and found that individuals commonly described their sensations associated with the 0-10 RPE scale using muscle sensations when both recalling exercise and after the completion of an acute exercise trial on an arm cycle ergometer. Lastly, we investigated the relationship between psychological and physiological measures and RPE during an arm cycling exercise during a maximal graded exercise test, high intensity interval training, and moderate intensity continuous training using a crossover experimental design in both non-disabled individuals and individuals who were mobility impaired due to SCI. While there were no relationships between any variable and RPE in non-disabled individuals, age and triceps strength predicted central RPE and peak feeling scale predicted peripheral RPE in individuals with an SCI. These mixed methods results collectively suggest that muscle strength, not heart rate, is the strongest predictor of perceived exertion especially in clinical populations completing high intensity exercise. Our novel findings suggest that RPE is regulated through a system of psychological and physiological phenomena, strongly related to muscle sensations arising from the working muscle groups and may have utility and relevance in complementing measures of exercise intensity for a broad range of individuals across the spectrum of health and disease. Future studies should examine the use of muscle sensation descriptions as descriptors of exercise intensity prior to the development of high intensity exercise guidelines in clinical populations, such as individuals with SCI. / Thesis / Candidate in Philosophy / It has been well established that heart rate and ratings of perceived exertion are related in young, healthy individuals, however the nuances of the relationships between other contributors and how clinical populations feel during exercise remain unclear. Using mixed methods, this research sought to determine what sensations help people determine how they feel during exercise, with a focus on high intensity interval training exercise. Our results show that muscle strength may be a key determinant in the perception of effort in individuals with a spinal cord injury and in clinical populations during arm and leg maximal graded exercise tests, but the relationships between physiological variables and perceptions of arm effort in non-impaired individuals remains to be determined. Sensations of effort are regulated through a variety of different mechanisms that vary with population, and the relationships depend on the parameters (e.g., exercise modality and intensity) of the exercise. Future studies should be conducted to determine the individual contributions of different body systems to perceived exertion during exercise in a wide range of populations.